Merge branch 'x86/kdump' into locking/kcsan, to resolve conflicts

Conflicts:
	arch/x86/purgatory/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>

46 files changed, 1946 insertions, 1243 deletions

diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
index 327b3ebf23bf..0271b22e063f 100644
--- a/mm/Kconfig.debug
+++ b/mm/Kconfig.debug
@@ -117,3 +117,24 @@ config DEBUG_RODATA_TEST
     depends on STRICT_KERNEL_RWX
     ---help---
       This option enables a testcase for the setting rodata read-only.
+
+config GENERIC_PTDUMP
+	bool
+
+config PTDUMP_CORE
+	bool
+
+config PTDUMP_DEBUGFS
+	bool "Export kernel pagetable layout to userspace via debugfs"
+	depends on DEBUG_KERNEL
+	depends on DEBUG_FS
+	depends on GENERIC_PTDUMP
+	select PTDUMP_CORE
+	help
+	  Say Y here if you want to show the kernel pagetable layout in a
+	  debugfs file. This information is only useful for kernel developers
+	  who are working in architecture specific areas of the kernel.
+	  It is probably not a good idea to enable this feature in a production
+	  kernel.
+
+	  If in doubt, say N.
diff --git a/mm/Makefile b/mm/Makefile
index f14ac8dc9bf1..c9696f3ec840 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -28,6 +28,7 @@ KCOV_INSTRUMENT_kmemleak.o := n
 KCOV_INSTRUMENT_memcontrol.o := n
 KCOV_INSTRUMENT_mmzone.o := n
 KCOV_INSTRUMENT_vmstat.o := n
+KCOV_INSTRUMENT_failslab.o := n
 
 CFLAGS_init-mm.o += $(call cc-disable-warning, override-init)
 CFLAGS_init-mm.o += $(call cc-disable-warning, initializer-overrides)
@@ -116,3 +117,4 @@ obj-$(CONFIG_ZONE_DEVICE) += memremap.o
 obj-$(CONFIG_HMM_MIRROR) += hmm.o
 obj-$(CONFIG_MEMFD_CREATE) += memfd.o
 obj-$(CONFIG_MAPPING_DIRTY_HELPERS) += mapping_dirty_helpers.o
+obj-$(CONFIG_PTDUMP_CORE) += ptdump.o
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index c360f6a6c844..62f05f605fb5 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -21,6 +21,7 @@ struct backing_dev_info noop_backing_dev_info = {
 EXPORT_SYMBOL_GPL(noop_backing_dev_info);
 
 static struct class *bdi_class;
+const char *bdi_unknown_name = "(unknown)";
 
 /*
  * bdi_lock protects bdi_tree and updates to bdi_list. bdi_list has RCU
diff --git a/mm/debug.c b/mm/debug.c
index 0461df1207cb..ecccd9f17801 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -46,7 +46,15 @@ void __dump_page(struct page *page, const char *reason)
 {
 	struct address_space *mapping;
 	bool page_poisoned = PagePoisoned(page);
+	/*
+	 * Accessing the pageblock without the zone lock. It could change to
+	 * "isolate" again in the meantime, but since we are just dumping the
+	 * state for debugging, it should be fine to accept a bit of
+	 * inaccuracy here due to racing.
+	 */
+	bool page_cma = is_migrate_cma_page(page);
 	int mapcount;
+	char *type = "";
 
 	/*
 	 * If struct page is poisoned don't access Page*() functions as that
@@ -78,9 +86,9 @@ void __dump_page(struct page *page, const char *reason)
 			page, page_ref_count(page), mapcount,
 			page->mapping, page_to_pgoff(page));
 	if (PageKsm(page))
-		pr_warn("ksm flags: %#lx(%pGp)\n", page->flags, &page->flags);
+		type = "ksm ";
 	else if (PageAnon(page))
-		pr_warn("anon flags: %#lx(%pGp)\n", page->flags, &page->flags);
+		type = "anon ";
 	else if (mapping) {
 		if (mapping->host && mapping->host->i_dentry.first) {
 			struct dentry *dentry;
@@ -88,10 +96,12 @@ void __dump_page(struct page *page, const char *reason)
 			pr_warn("%ps name:\"%pd\"\n", mapping->a_ops, dentry);
 		} else
 			pr_warn("%ps\n", mapping->a_ops);
-		pr_warn("flags: %#lx(%pGp)\n", page->flags, &page->flags);
 	}
 	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
 
+	pr_warn("%sflags: %#lx(%pGp)%s\n", type, page->flags, &page->flags,
+		page_cma ? " CMA" : "");
+
 hex_only:
 	print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
 			sizeof(unsigned long), page,
@@ -153,7 +163,7 @@ void dump_mm(const struct mm_struct *mm)
 #endif
 		"exe_file %px\n"
 #ifdef CONFIG_MMU_NOTIFIER
-		"mmu_notifier_mm %px\n"
+		"notifier_subscriptions %px\n"
 #endif
 #ifdef CONFIG_NUMA_BALANCING
 		"numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
@@ -185,7 +195,7 @@ void dump_mm(const struct mm_struct *mm)
 #endif
 		mm->exe_file,
 #ifdef CONFIG_MMU_NOTIFIER
-		mm->mmu_notifier_mm,
+		mm->notifier_subscriptions,
 #endif
 #ifdef CONFIG_NUMA_BALANCING
 		mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
diff --git a/mm/early_ioremap.c b/mm/early_ioremap.c
index 1826f191e72c..a0018ad1a1f6 100644
--- a/mm/early_ioremap.c
+++ b/mm/early_ioremap.c
@@ -121,8 +121,8 @@ __early_ioremap(resource_size_t phys_addr, unsigned long size, pgprot_t prot)
 		}
 	}
 
-	if (WARN(slot < 0, "%s(%08llx, %08lx) not found slot\n",
-		 __func__, (u64)phys_addr, size))
+	if (WARN(slot < 0, "%s(%pa, %08lx) not found slot\n",
+		 __func__, &phys_addr, size))
 		return NULL;
 
 	/* Don't allow wraparound or zero size */
@@ -158,8 +158,8 @@ __early_ioremap(resource_size_t phys_addr, unsigned long size, pgprot_t prot)
 		--idx;
 		--nrpages;
 	}
-	WARN(early_ioremap_debug, "%s(%08llx, %08lx) [%d] => %08lx + %08lx\n",
-	     __func__, (u64)phys_addr, size, slot, offset, slot_virt[slot]);
+	WARN(early_ioremap_debug, "%s(%pa, %08lx) [%d] => %08lx + %08lx\n",
+	     __func__, &phys_addr, size, slot, offset, slot_virt[slot]);
 
 	prev_map[slot] = (void __iomem *)(offset + slot_virt[slot]);
 	return prev_map[slot];
diff --git a/mm/filemap.c b/mm/filemap.c
index bf6aa30be58d..1784478270e1 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -632,33 +632,6 @@ static bool mapping_needs_writeback(struct address_space *mapping)
 	return mapping->nrpages;
 }
 
-int filemap_write_and_wait(struct address_space *mapping)
-{
-	int err = 0;
-
-	if (mapping_needs_writeback(mapping)) {
-		err = filemap_fdatawrite(mapping);
-		/*
-		 * Even if the above returned error, the pages may be
-		 * written partially (e.g. -ENOSPC), so we wait for it.
-		 * But the -EIO is special case, it may indicate the worst
-		 * thing (e.g. bug) happened, so we avoid waiting for it.
-		 */
-		if (err != -EIO) {
-			int err2 = filemap_fdatawait(mapping);
-			if (!err)
-				err = err2;
-		} else {
-			/* Clear any previously stored errors */
-			filemap_check_errors(mapping);
-		}
-	} else {
-		err = filemap_check_errors(mapping);
-	}
-	return err;
-}
-EXPORT_SYMBOL(filemap_write_and_wait);
-
 /**
  * filemap_write_and_wait_range - write out & wait on a file range
  * @mapping:	the address_space for the pages
@@ -680,7 +653,12 @@ int filemap_write_and_wait_range(struct address_space *mapping,
 	if (mapping_needs_writeback(mapping)) {
 		err = __filemap_fdatawrite_range(mapping, lstart, lend,
 						 WB_SYNC_ALL);
-		/* See comment of filemap_write_and_wait() */
+		/*
+		 * Even if the above returned error, the pages may be
+		 * written partially (e.g. -ENOSPC), so we wait for it.
+		 * But the -EIO is special case, it may indicate the worst
+		 * thing (e.g. bug) happened, so we avoid waiting for it.
+		 */
 		if (err != -EIO) {
 			int err2 = filemap_fdatawait_range(mapping,
 						lstart, lend);
diff --git a/mm/gup.c b/mm/gup.c
index 7646bf993b25..1b521e0ac1de 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -29,8 +29,23 @@ struct follow_page_context {
 	unsigned int page_mask;
 };
 
+/*
+ * Return the compound head page with ref appropriately incremented,
+ * or NULL if that failed.
+ */
+static inline struct page *try_get_compound_head(struct page *page, int refs)
+{
+	struct page *head = compound_head(page);
+
+	if (WARN_ON_ONCE(page_ref_count(head) < 0))
+		return NULL;
+	if (unlikely(!page_cache_add_speculative(head, refs)))
+		return NULL;
+	return head;
+}
+
 /**
- * put_user_pages_dirty_lock() - release and optionally dirty gup-pinned pages
+ * unpin_user_pages_dirty_lock() - release and optionally dirty gup-pinned pages
  * @pages:  array of pages to be maybe marked dirty, and definitely released.
  * @npages: number of pages in the @pages array.
  * @make_dirty: whether to mark the pages dirty
@@ -40,19 +55,19 @@ struct follow_page_context {
  *
  * For each page in the @pages array, make that page (or its head page, if a
  * compound page) dirty, if @make_dirty is true, and if the page was previously
- * listed as clean. In any case, releases all pages using put_user_page(),
- * possibly via put_user_pages(), for the non-dirty case.
+ * listed as clean. In any case, releases all pages using unpin_user_page(),
+ * possibly via unpin_user_pages(), for the non-dirty case.
  *
- * Please see the put_user_page() documentation for details.
+ * Please see the unpin_user_page() documentation for details.
  *
  * set_page_dirty_lock() is used internally. If instead, set_page_dirty() is
  * required, then the caller should a) verify that this is really correct,
  * because _lock() is usually required, and b) hand code it:
- * set_page_dirty_lock(), put_user_page().
+ * set_page_dirty_lock(), unpin_user_page().
  *
  */
-void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
-			       bool make_dirty)
+void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
+				 bool make_dirty)
 {
 	unsigned long index;
 
@@ -63,7 +78,7 @@ void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
 	 */
 
 	if (!make_dirty) {
-		put_user_pages(pages, npages);
+		unpin_user_pages(pages, npages);
 		return;
 	}
 
@@ -91,21 +106,21 @@ void put_user_pages_dirty_lock(struct page **pages, unsigned long npages,
 		 */
 		if (!PageDirty(page))
 			set_page_dirty_lock(page);
-		put_user_page(page);
+		unpin_user_page(page);
 	}
 }
-EXPORT_SYMBOL(put_user_pages_dirty_lock);
+EXPORT_SYMBOL(unpin_user_pages_dirty_lock);
 
 /**
- * put_user_pages() - release an array of gup-pinned pages.
+ * unpin_user_pages() - release an array of gup-pinned pages.
  * @pages:  array of pages to be marked dirty and released.
  * @npages: number of pages in the @pages array.
  *
- * For each page in the @pages array, release the page using put_user_page().
+ * For each page in the @pages array, release the page using unpin_user_page().
  *
- * Please see the put_user_page() documentation for details.
+ * Please see the unpin_user_page() documentation for details.
  */
-void put_user_pages(struct page **pages, unsigned long npages)
+void unpin_user_pages(struct page **pages, unsigned long npages)
 {
 	unsigned long index;
 
@@ -115,9 +130,9 @@ void put_user_pages(struct page **pages, unsigned long npages)
 	 * single operation to the head page should suffice.
 	 */
 	for (index = 0; index < npages; index++)
-		put_user_page(pages[index]);
+		unpin_user_page(pages[index]);
 }
-EXPORT_SYMBOL(put_user_pages);
+EXPORT_SYMBOL(unpin_user_pages);
 
 #ifdef CONFIG_MMU
 static struct page *no_page_table(struct vm_area_struct *vma,
@@ -179,6 +194,10 @@ static struct page *follow_page_pte(struct vm_area_struct *vma,
 	spinlock_t *ptl;
 	pte_t *ptep, pte;
 
+	/* FOLL_GET and FOLL_PIN are mutually exclusive. */
+	if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) ==
+			 (FOLL_PIN | FOLL_GET)))
+		return ERR_PTR(-EINVAL);
 retry:
 	if (unlikely(pmd_bad(*pmd)))
 		return no_page_table(vma, flags);
@@ -323,7 +342,7 @@ static struct page *follow_pmd_mask(struct vm_area_struct *vma,
 	pmdval = READ_ONCE(*pmd);
 	if (pmd_none(pmdval))
 		return no_page_table(vma, flags);
-	if (pmd_huge(pmdval) && vma->vm_flags & VM_HUGETLB) {
+	if (pmd_huge(pmdval) && is_vm_hugetlb_page(vma)) {
 		page = follow_huge_pmd(mm, address, pmd, flags);
 		if (page)
 			return page;
@@ -433,7 +452,7 @@ static struct page *follow_pud_mask(struct vm_area_struct *vma,
 	pud = pud_offset(p4dp, address);
 	if (pud_none(*pud))
 		return no_page_table(vma, flags);
-	if (pud_huge(*pud) && vma->vm_flags & VM_HUGETLB) {
+	if (pud_huge(*pud) && is_vm_hugetlb_page(vma)) {
 		page = follow_huge_pud(mm, address, pud, flags);
 		if (page)
 			return page;
@@ -796,7 +815,7 @@ static long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 
 	start = untagged_addr(start);
 
-	VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET));
+	VM_BUG_ON(!!pages != !!(gup_flags & (FOLL_GET | FOLL_PIN)));
 
 	/*
 	 * If FOLL_FORCE is set then do not force a full fault as the hinting
@@ -1020,7 +1039,16 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
 		BUG_ON(*locked != 1);
 	}
 
-	if (pages)
+	/*
+	 * FOLL_PIN and FOLL_GET are mutually exclusive. Traditional behavior
+	 * is to set FOLL_GET if the caller wants pages[] filled in (but has
+	 * carelessly failed to specify FOLL_GET), so keep doing that, but only
+	 * for FOLL_GET, not for the newer FOLL_PIN.
+	 *
+	 * FOLL_PIN always expects pages to be non-null, but no need to assert
+	 * that here, as any failures will be obvious enough.
+	 */
+	if (pages && !(flags & FOLL_PIN))
 		flags |= FOLL_GET;
 
 	pages_done = 0;
@@ -1096,88 +1124,6 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
 	return pages_done;
 }
 
-/*
- * get_user_pages_remote() - pin user pages in memory
- * @tsk:	the task_struct to use for page fault accounting, or
- *		NULL if faults are not to be recorded.
- * @mm:		mm_struct of target mm
- * @start:	starting user address
- * @nr_pages:	number of pages from start to pin
- * @gup_flags:	flags modifying lookup behaviour
- * @pages:	array that receives pointers to the pages pinned.
- *		Should be at least nr_pages long. Or NULL, if caller
- *		only intends to ensure the pages are faulted in.
- * @vmas:	array of pointers to vmas corresponding to each page.
- *		Or NULL if the caller does not require them.
- * @locked:	pointer to lock flag indicating whether lock is held and
- *		subsequently whether VM_FAULT_RETRY functionality can be
- *		utilised. Lock must initially be held.
- *
- * Returns either number of pages pinned (which may be less than the
- * number requested), or an error. Details about the return value:
- *
- * -- If nr_pages is 0, returns 0.
- * -- If nr_pages is >0, but no pages were pinned, returns -errno.
- * -- If nr_pages is >0, and some pages were pinned, returns the number of
- *    pages pinned. Again, this may be less than nr_pages.
- *
- * The caller is responsible for releasing returned @pages, via put_page().
- *
- * @vmas are valid only as long as mmap_sem is held.
- *
- * Must be called with mmap_sem held for read or write.
- *
- * get_user_pages walks a process's page tables and takes a reference to
- * each struct page that each user address corresponds to at a given
- * instant. That is, it takes the page that would be accessed if a user
- * thread accesses the given user virtual address at that instant.
- *
- * This does not guarantee that the page exists in the user mappings when
- * get_user_pages returns, and there may even be a completely different
- * page there in some cases (eg. if mmapped pagecache has been invalidated
- * and subsequently re faulted). However it does guarantee that the page
- * won't be freed completely. And mostly callers simply care that the page
- * contains data that was valid *at some point in time*. Typically, an IO
- * or similar operation cannot guarantee anything stronger anyway because
- * locks can't be held over the syscall boundary.
- *
- * If gup_flags & FOLL_WRITE == 0, the page must not be written to. If the page
- * is written to, set_page_dirty (or set_page_dirty_lock, as appropriate) must
- * be called after the page is finished with, and before put_page is called.
- *
- * get_user_pages is typically used for fewer-copy IO operations, to get a
- * handle on the memory by some means other than accesses via the user virtual
- * addresses. The pages may be submitted for DMA to devices or accessed via
- * their kernel linear mapping (via the kmap APIs). Care should be taken to
- * use the correct cache flushing APIs.
- *
- * See also get_user_pages_fast, for performance critical applications.
- *
- * get_user_pages should be phased out in favor of
- * get_user_pages_locked|unlocked or get_user_pages_fast. Nothing
- * should use get_user_pages because it cannot pass
- * FAULT_FLAG_ALLOW_RETRY to handle_mm_fault.
- */
-long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
-		unsigned long start, unsigned long nr_pages,
-		unsigned int gup_flags, struct page **pages,
-		struct vm_area_struct **vmas, int *locked)
-{
-	/*
-	 * FIXME: Current FOLL_LONGTERM behavior is incompatible with
-	 * FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on
-	 * vmas.  As there are no users of this flag in this call we simply
-	 * disallow this option for now.
-	 */
-	if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM))
-		return -EINVAL;
-
-	return __get_user_pages_locked(tsk, mm, start, nr_pages, pages, vmas,
-				       locked,
-				       gup_flags | FOLL_TOUCH | FOLL_REMOTE);
-}
-EXPORT_SYMBOL(get_user_pages_remote);
-
 /**
  * populate_vma_page_range() -  populate a range of pages in the vma.
  * @vma:   target vma
@@ -1612,6 +1558,116 @@ static __always_inline long __gup_longterm_locked(struct task_struct *tsk,
 #endif /* CONFIG_FS_DAX || CONFIG_CMA */
 
 /*
+ * get_user_pages_remote() - pin user pages in memory
+ * @tsk:	the task_struct to use for page fault accounting, or
+ *		NULL if faults are not to be recorded.
+ * @mm:		mm_struct of target mm
+ * @start:	starting user address
+ * @nr_pages:	number of pages from start to pin
+ * @gup_flags:	flags modifying lookup behaviour
+ * @pages:	array that receives pointers to the pages pinned.
+ *		Should be at least nr_pages long. Or NULL, if caller
+ *		only intends to ensure the pages are faulted in.
+ * @vmas:	array of pointers to vmas corresponding to each page.
+ *		Or NULL if the caller does not require them.
+ * @locked:	pointer to lock flag indicating whether lock is held and
+ *		subsequently whether VM_FAULT_RETRY functionality can be
+ *		utilised. Lock must initially be held.
+ *
+ * Returns either number of pages pinned (which may be less than the
+ * number requested), or an error. Details about the return value:
+ *
+ * -- If nr_pages is 0, returns 0.
+ * -- If nr_pages is >0, but no pages were pinned, returns -errno.
+ * -- If nr_pages is >0, and some pages were pinned, returns the number of
+ *    pages pinned. Again, this may be less than nr_pages.
+ *
+ * The caller is responsible for releasing returned @pages, via put_page().
+ *
+ * @vmas are valid only as long as mmap_sem is held.
+ *
+ * Must be called with mmap_sem held for read or write.
+ *
+ * get_user_pages walks a process's page tables and takes a reference to
+ * each struct page that each user address corresponds to at a given
+ * instant. That is, it takes the page that would be accessed if a user
+ * thread accesses the given user virtual address at that instant.
+ *
+ * This does not guarantee that the page exists in the user mappings when
+ * get_user_pages returns, and there may even be a completely different
+ * page there in some cases (eg. if mmapped pagecache has been invalidated
+ * and subsequently re faulted). However it does guarantee that the page
+ * won't be freed completely. And mostly callers simply care that the page
+ * contains data that was valid *at some point in time*. Typically, an IO
+ * or similar operation cannot guarantee anything stronger anyway because
+ * locks can't be held over the syscall boundary.
+ *
+ * If gup_flags & FOLL_WRITE == 0, the page must not be written to. If the page
+ * is written to, set_page_dirty (or set_page_dirty_lock, as appropriate) must
+ * be called after the page is finished with, and before put_page is called.
+ *
+ * get_user_pages is typically used for fewer-copy IO operations, to get a
+ * handle on the memory by some means other than accesses via the user virtual
+ * addresses. The pages may be submitted for DMA to devices or accessed via
+ * their kernel linear mapping (via the kmap APIs). Care should be taken to
+ * use the correct cache flushing APIs.
+ *
+ * See also get_user_pages_fast, for performance critical applications.
+ *
+ * get_user_pages should be phased out in favor of
+ * get_user_pages_locked|unlocked or get_user_pages_fast. Nothing
+ * should use get_user_pages because it cannot pass
+ * FAULT_FLAG_ALLOW_RETRY to handle_mm_fault.
+ */
+#ifdef CONFIG_MMU
+long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
+		unsigned long start, unsigned long nr_pages,
+		unsigned int gup_flags, struct page **pages,
+		struct vm_area_struct **vmas, int *locked)
+{
+	/*
+	 * FOLL_PIN must only be set internally by the pin_user_pages*() APIs,
+	 * never directly by the caller, so enforce that with an assertion:
+	 */
+	if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
+		return -EINVAL;
+
+	/*
+	 * Parts of FOLL_LONGTERM behavior are incompatible with
+	 * FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on
+	 * vmas. However, this only comes up if locked is set, and there are
+	 * callers that do request FOLL_LONGTERM, but do not set locked. So,
+	 * allow what we can.
+	 */
+	if (gup_flags & FOLL_LONGTERM) {
+		if (WARN_ON_ONCE(locked))
+			return -EINVAL;
+		/*
+		 * This will check the vmas (even if our vmas arg is NULL)
+		 * and return -ENOTSUPP if DAX isn't allowed in this case:
+		 */
+		return __gup_longterm_locked(tsk, mm, start, nr_pages, pages,
+					     vmas, gup_flags | FOLL_TOUCH |
+					     FOLL_REMOTE);
+	}
+
+	return __get_user_pages_locked(tsk, mm, start, nr_pages, pages, vmas,
+				       locked,
+				       gup_flags | FOLL_TOUCH | FOLL_REMOTE);
+}
+EXPORT_SYMBOL(get_user_pages_remote);
+
+#else /* CONFIG_MMU */
+long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
+			   unsigned long start, unsigned long nr_pages,
+			   unsigned int gup_flags, struct page **pages,
+			   struct vm_area_struct **vmas, int *locked)
+{
+	return 0;
+}
+#endif /* !CONFIG_MMU */
+
+/*
  * This is the same as get_user_pages_remote(), just with a
  * less-flexible calling convention where we assume that the task
  * and mm being operated on are the current task's and don't allow
@@ -1622,6 +1678,13 @@ long get_user_pages(unsigned long start, unsigned long nr_pages,
 		unsigned int gup_flags, struct page **pages,
 		struct vm_area_struct **vmas)
 {
+	/*
+	 * FOLL_PIN must only be set internally by the pin_user_pages*() APIs,
+	 * never directly by the caller, so enforce that with an assertion:
+	 */
+	if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
+		return -EINVAL;
+
 	return __gup_longterm_locked(current, current->mm, start, nr_pages,
 				     pages, vmas, gup_flags | FOLL_TOUCH);
 }
@@ -1729,7 +1792,7 @@ EXPORT_SYMBOL(get_user_pages_unlocked);
  * Before activating this code, please be aware that the following assumptions
  * are currently made:
  *
- *  *) Either HAVE_RCU_TABLE_FREE is enabled, and tlb_remove_table() is used to
+ *  *) Either MMU_GATHER_RCU_TABLE_FREE is enabled, and tlb_remove_table() is used to
  *  free pages containing page tables or TLB flushing requires IPI broadcast.
  *
  *  *) ptes can be read atomically by the architecture.
@@ -1807,20 +1870,6 @@ static void __maybe_unused undo_dev_pagemap(int *nr, int nr_start,
 	}
 }
 
-/*
- * Return the compund head page with ref appropriately incremented,
- * or NULL if that failed.
- */
-static inline struct page *try_get_compound_head(struct page *page, int refs)
-{
-	struct page *head = compound_head(page);
-	if (WARN_ON_ONCE(page_ref_count(head) < 0))
-		return NULL;
-	if (unlikely(!page_cache_add_speculative(head, refs)))
-		return NULL;
-	return head;
-}
-
 #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
 static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
 			 unsigned int flags, struct page **pages, int *nr)
@@ -1978,6 +2027,29 @@ static int __gup_device_huge_pud(pud_t pud, pud_t *pudp, unsigned long addr,
 }
 #endif
 
+static int record_subpages(struct page *page, unsigned long addr,
+			   unsigned long end, struct page **pages)
+{
+	int nr;
+
+	for (nr = 0; addr != end; addr += PAGE_SIZE)
+		pages[nr++] = page++;
+
+	return nr;
+}
+
+static void put_compound_head(struct page *page, int refs)
+{
+	VM_BUG_ON_PAGE(page_ref_count(page) < refs, page);
+	/*
+	 * Calling put_page() for each ref is unnecessarily slow. Only the last
+	 * ref needs a put_page().
+	 */
+	if (refs > 1)
+		page_ref_sub(page, refs - 1);
+	put_page(page);
+}
+
 #ifdef CONFIG_ARCH_HAS_HUGEPD
 static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
 				      unsigned long sz)
@@ -2007,32 +2079,20 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 	/* hugepages are never "special" */
 	VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
 
-	refs = 0;
 	head = pte_page(pte);
-
 	page = head + ((addr & (sz-1)) >> PAGE_SHIFT);
-	do {
-		VM_BUG_ON(compound_head(page) != head);
-		pages[*nr] = page;
-		(*nr)++;
-		page++;
-		refs++;
-	} while (addr += PAGE_SIZE, addr != end);
+	refs = record_subpages(page, addr, end, pages + *nr);
 
 	head = try_get_compound_head(head, refs);
-	if (!head) {
-		*nr -= refs;
+	if (!head)
 		return 0;
-	}
 
 	if (unlikely(pte_val(pte) != pte_val(*ptep))) {
-		/* Could be optimized better */
-		*nr -= refs;
-		while (refs--)
-			put_page(head);
+		put_compound_head(head, refs);
 		return 0;
 	}
 
+	*nr += refs;
 	SetPageReferenced(head);
 	return 1;
 }
@@ -2079,28 +2139,19 @@ static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
 		return __gup_device_huge_pmd(orig, pmdp, addr, end, pages, nr);
 	}
 
-	refs = 0;
 	page = pmd_page(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
-	do {
-		pages[*nr] = page;
-		(*nr)++;
-		page++;
-		refs++;
-	} while (addr += PAGE_SIZE, addr != end);
+	refs = record_subpages(page, addr, end, pages + *nr);
 
 	head = try_get_compound_head(pmd_page(orig), refs);
-	if (!head) {
-		*nr -= refs;
+	if (!head)
 		return 0;
-	}
 
 	if (unlikely(pmd_val(orig) != pmd_val(*pmdp))) {
-		*nr -= refs;
-		while (refs--)
-			put_page(head);
+		put_compound_head(head, refs);
 		return 0;
 	}
 
+	*nr += refs;
 	SetPageReferenced(head);
 	return 1;
 }
@@ -2120,28 +2171,19 @@ static int gup_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
 		return __gup_device_huge_pud(orig, pudp, addr, end, pages, nr);
 	}
 
-	refs = 0;
 	page = pud_page(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
-	do {
-		pages[*nr] = page;
-		(*nr)++;
-		page++;
-		refs++;
-	} while (addr += PAGE_SIZE, addr != end);
+	refs = record_subpages(page, addr, end, pages + *nr);
 
 	head = try_get_compound_head(pud_page(orig), refs);
-	if (!head) {
-		*nr -= refs;
+	if (!head)
 		return 0;
-	}
 
 	if (unlikely(pud_val(orig) != pud_val(*pudp))) {
-		*nr -= refs;
-		while (refs--)
-			put_page(head);
+		put_compound_head(head, refs);
 		return 0;
 	}
 
+	*nr += refs;
 	SetPageReferenced(head);
 	return 1;
 }
@@ -2157,28 +2199,20 @@ static int gup_huge_pgd(pgd_t orig, pgd_t *pgdp, unsigned long addr,
 		return 0;
 
 	BUILD_BUG_ON(pgd_devmap(orig));
-	refs = 0;
+
 	page = pgd_page(orig) + ((addr & ~PGDIR_MASK) >> PAGE_SHIFT);
-	do {
-		pages[*nr] = page;
-		(*nr)++;
-		page++;
-		refs++;
-	} while (addr += PAGE_SIZE, addr != end);
+	refs = record_subpages(page, addr, end, pages + *nr);
 
 	head = try_get_compound_head(pgd_page(orig), refs);
-	if (!head) {
-		*nr -= refs;
+	if (!head)
 		return 0;
-	}
 
 	if (unlikely(pgd_val(orig) != pgd_val(*pgdp))) {
-		*nr -= refs;
-		while (refs--)
-			put_page(head);
+		put_compound_head(head, refs);
 		return 0;
 	}
 
+	*nr += refs;
 	SetPageReferenced(head);
 	return 1;
 }
@@ -2237,7 +2271,7 @@ static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end,
 		pud_t pud = READ_ONCE(*pudp);
 
 		next = pud_addr_end(addr, end);
-		if (pud_none(pud))
+		if (unlikely(!pud_present(pud)))
 			return 0;
 		if (unlikely(pud_huge(pud))) {
 			if (!gup_huge_pud(pud, pudp, addr, next, flags,
@@ -2393,29 +2427,15 @@ static int __gup_longterm_unlocked(unsigned long start, int nr_pages,
 	return ret;
 }
 
-/**
- * get_user_pages_fast() - pin user pages in memory
- * @start:	starting user address
- * @nr_pages:	number of pages from start to pin
- * @gup_flags:	flags modifying pin behaviour
- * @pages:	array that receives pointers to the pages pinned.
- *		Should be at least nr_pages long.
- *
- * Attempt to pin user pages in memory without taking mm->mmap_sem.
- * If not successful, it will fall back to taking the lock and
- * calling get_user_pages().
- *
- * Returns number of pages pinned. This may be fewer than the number
- * requested. If nr_pages is 0 or negative, returns 0. If no pages
- * were pinned, returns -errno.
- */
-int get_user_pages_fast(unsigned long start, int nr_pages,
-			unsigned int gup_flags, struct page **pages)
+static int internal_get_user_pages_fast(unsigned long start, int nr_pages,
+					unsigned int gup_flags,
+					struct page **pages)
 {
 	unsigned long addr, len, end;
 	int nr = 0, ret = 0;
 
-	if (WARN_ON_ONCE(gup_flags & ~(FOLL_WRITE | FOLL_LONGTERM)))
+	if (WARN_ON_ONCE(gup_flags & ~(FOLL_WRITE | FOLL_LONGTERM |
+				       FOLL_FORCE | FOLL_PIN)))
 		return -EINVAL;
 
 	start = untagged_addr(start) & PAGE_MASK;
@@ -2455,4 +2475,103 @@ int get_user_pages_fast(unsigned long start, int nr_pages,
 
 	return ret;
 }
+
+/**
+ * get_user_pages_fast() - pin user pages in memory
+ * @start:	starting user address
+ * @nr_pages:	number of pages from start to pin
+ * @gup_flags:	flags modifying pin behaviour
+ * @pages:	array that receives pointers to the pages pinned.
+ *		Should be at least nr_pages long.
+ *
+ * Attempt to pin user pages in memory without taking mm->mmap_sem.
+ * If not successful, it will fall back to taking the lock and
+ * calling get_user_pages().
+ *
+ * Returns number of pages pinned. This may be fewer than the number requested.
+ * If nr_pages is 0 or negative, returns 0. If no pages were pinned, returns
+ * -errno.
+ */
+int get_user_pages_fast(unsigned long start, int nr_pages,
+			unsigned int gup_flags, struct page **pages)
+{
+	/*
+	 * FOLL_PIN must only be set internally by the pin_user_pages*() APIs,
+	 * never directly by the caller, so enforce that:
+	 */
+	if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
+		return -EINVAL;
+
+	return internal_get_user_pages_fast(start, nr_pages, gup_flags, pages);
+}
 EXPORT_SYMBOL_GPL(get_user_pages_fast);
+
+/**
+ * pin_user_pages_fast() - pin user pages in memory without taking locks
+ *
+ * For now, this is a placeholder function, until various call sites are
+ * converted to use the correct get_user_pages*() or pin_user_pages*() API. So,
+ * this is identical to get_user_pages_fast().
+ *
+ * This is intended for Case 1 (DIO) in Documentation/vm/pin_user_pages.rst. It
+ * is NOT intended for Case 2 (RDMA: long-term pins).
+ */
+int pin_user_pages_fast(unsigned long start, int nr_pages,
+			unsigned int gup_flags, struct page **pages)
+{
+	/*
+	 * This is a placeholder, until the pin functionality is activated.
+	 * Until then, just behave like the corresponding get_user_pages*()
+	 * routine.
+	 */
+	return get_user_pages_fast(start, nr_pages, gup_flags, pages);
+}
+EXPORT_SYMBOL_GPL(pin_user_pages_fast);
+
+/**
+ * pin_user_pages_remote() - pin pages of a remote process (task != current)
+ *
+ * For now, this is a placeholder function, until various call sites are
+ * converted to use the correct get_user_pages*() or pin_user_pages*() API. So,
+ * this is identical to get_user_pages_remote().
+ *
+ * This is intended for Case 1 (DIO) in Documentation/vm/pin_user_pages.rst. It
+ * is NOT intended for Case 2 (RDMA: long-term pins).
+ */
+long pin_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
+			   unsigned long start, unsigned long nr_pages,
+			   unsigned int gup_flags, struct page **pages,
+			   struct vm_area_struct **vmas, int *locked)
+{
+	/*
+	 * This is a placeholder, until the pin functionality is activated.
+	 * Until then, just behave like the corresponding get_user_pages*()
+	 * routine.
+	 */
+	return get_user_pages_remote(tsk, mm, start, nr_pages, gup_flags, pages,
+				     vmas, locked);
+}
+EXPORT_SYMBOL(pin_user_pages_remote);
+
+/**
+ * pin_user_pages() - pin user pages in memory for use by other devices
+ *
+ * For now, this is a placeholder function, until various call sites are
+ * converted to use the correct get_user_pages*() or pin_user_pages*() API. So,
+ * this is identical to get_user_pages().
+ *
+ * This is intended for Case 1 (DIO) in Documentation/vm/pin_user_pages.rst. It
+ * is NOT intended for Case 2 (RDMA: long-term pins).
+ */
+long pin_user_pages(unsigned long start, unsigned long nr_pages,
+		    unsigned int gup_flags, struct page **pages,
+		    struct vm_area_struct **vmas)
+{
+	/*
+	 * This is a placeholder, until the pin functionality is activated.
+	 * Until then, just behave like the corresponding get_user_pages*()
+	 * routine.
+	 */
+	return get_user_pages(start, nr_pages, gup_flags, pages, vmas);
+}
+EXPORT_SYMBOL(pin_user_pages);
diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c
index ad9d5b1c4473..8dba38e79a9f 100644
--- a/mm/gup_benchmark.c
+++ b/mm/gup_benchmark.c
@@ -49,18 +49,21 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
 			nr = (next - addr) / PAGE_SIZE;
 		}
 
+		/* Filter out most gup flags: only allow a tiny subset here: */
+		gup->flags &= FOLL_WRITE;
+
 		switch (cmd) {
 		case GUP_FAST_BENCHMARK:
-			nr = get_user_pages_fast(addr, nr, gup->flags & 1,
+			nr = get_user_pages_fast(addr, nr, gup->flags,
 						 pages + i);
 			break;
 		case GUP_LONGTERM_BENCHMARK:
 			nr = get_user_pages(addr, nr,
-					    (gup->flags & 1) | FOLL_LONGTERM,
+					    gup->flags | FOLL_LONGTERM,
 					    pages + i, NULL);
 			break;
 		case GUP_BENCHMARK:
-			nr = get_user_pages(addr, nr, gup->flags & 1, pages + i,
+			nr = get_user_pages(addr, nr, gup->flags, pages + i,
 					    NULL);
 			break;
 		default:
diff --git a/mm/highmem.c b/mm/highmem.c
index 107b10f9878e..64d8dea47dd1 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -29,7 +29,7 @@
 #include <linux/highmem.h>
 #include <linux/kgdb.h>
 #include <asm/tlbflush.h>
-
+#include <linux/vmalloc.h>
 
 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
 DEFINE_PER_CPU(int, __kmap_atomic_idx);
diff --git a/mm/hmm.c b/mm/hmm.c
index d379cb6496ae..72e5a6d9a417 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -186,7 +186,7 @@ static void hmm_range_need_fault(const struct hmm_vma_walk *hmm_vma_walk,
 }
 
 static int hmm_vma_walk_hole(unsigned long addr, unsigned long end,
-			     struct mm_walk *walk)
+			     __always_unused int depth, struct mm_walk *walk)
 {
 	struct hmm_vma_walk *hmm_vma_walk = walk->private;
 	struct hmm_range *range = hmm_vma_walk->range;
@@ -380,7 +380,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
 again:
 	pmd = READ_ONCE(*pmdp);
 	if (pmd_none(pmd))
-		return hmm_vma_walk_hole(start, end, walk);
+		return hmm_vma_walk_hole(start, end, -1, walk);
 
 	if (thp_migration_supported() && is_pmd_migration_entry(pmd)) {
 		bool fault, write_fault;
@@ -474,23 +474,32 @@ static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end,
 {
 	struct hmm_vma_walk *hmm_vma_walk = walk->private;
 	struct hmm_range *range = hmm_vma_walk->range;
-	unsigned long addr = start, next;
-	pmd_t *pmdp;
+	unsigned long addr = start;
 	pud_t pud;
-	int ret;
+	int ret = 0;
+	spinlock_t *ptl = pud_trans_huge_lock(pudp, walk->vma);
+
+	if (!ptl)
+		return 0;
+
+	/* Normally we don't want to split the huge page */
+	walk->action = ACTION_CONTINUE;
 
-again:
 	pud = READ_ONCE(*pudp);
-	if (pud_none(pud))
-		return hmm_vma_walk_hole(start, end, walk);
+	if (pud_none(pud)) {
+		ret = hmm_vma_walk_hole(start, end, -1, walk);
+		goto out_unlock;
+	}
 
 	if (pud_huge(pud) && pud_devmap(pud)) {
 		unsigned long i, npages, pfn;
 		uint64_t *pfns, cpu_flags;
 		bool fault, write_fault;
 
-		if (!pud_present(pud))
-			return hmm_vma_walk_hole(start, end, walk);
+		if (!pud_present(pud)) {
+			ret = hmm_vma_walk_hole(start, end, -1, walk);
+			goto out_unlock;
+		}
 
 		i = (addr - range->start) >> PAGE_SHIFT;
 		npages = (end - addr) >> PAGE_SHIFT;
@@ -499,16 +508,20 @@ again:
 		cpu_flags = pud_to_hmm_pfn_flags(range, pud);
 		hmm_range_need_fault(hmm_vma_walk, pfns, npages,
 				     cpu_flags, &fault, &write_fault);
-		if (fault || write_fault)
-			return hmm_vma_walk_hole_(addr, end, fault,
-						write_fault, walk);
+		if (fault || write_fault) {
+			ret = hmm_vma_walk_hole_(addr, end, fault,
+						 write_fault, walk);
+			goto out_unlock;
+		}
 
 		pfn = pud_pfn(pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
 		for (i = 0; i < npages; ++i, ++pfn) {
 			hmm_vma_walk->pgmap = get_dev_pagemap(pfn,
 					      hmm_vma_walk->pgmap);
-			if (unlikely(!hmm_vma_walk->pgmap))
-				return -EBUSY;
+			if (unlikely(!hmm_vma_walk->pgmap)) {
+				ret = -EBUSY;
+				goto out_unlock;
+			}
 			pfns[i] = hmm_device_entry_from_pfn(range, pfn) |
 				  cpu_flags;
 		}
@@ -517,22 +530,15 @@ again:
 			hmm_vma_walk->pgmap = NULL;
 		}
 		hmm_vma_walk->last = end;
-		return 0;
+		goto out_unlock;
 	}
 
-	split_huge_pud(walk->vma, pudp, addr);
-	if (pud_none(*pudp))
-		goto again;
+	/* Ask for the PUD to be split */
+	walk->action = ACTION_SUBTREE;
 
-	pmdp = pmd_offset(pudp, addr);
-	do {
-		next = pmd_addr_end(addr, end);
-		ret = hmm_vma_walk_pmd(pmdp, addr, next, walk);
-		if (ret)
-			return ret;
-	} while (pmdp++, addr = next, addr != end);
-
-	return 0;
+out_unlock:
+	spin_unlock(ptl);
+	return ret;
 }
 #else
 #define hmm_vma_walk_pud	NULL
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a88093213674..b08b199f9a11 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -177,16 +177,13 @@ static ssize_t enabled_store(struct kobject *kobj,
 {
 	ssize_t ret = count;
 
-	if (!memcmp("always", buf,
-		    min(sizeof("always")-1, count))) {
+	if (sysfs_streq(buf, "always")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flags);
 		set_bit(TRANSPARENT_HUGEPAGE_FLAG, &transparent_hugepage_flags);
-	} else if (!memcmp("madvise", buf,
-			   min(sizeof("madvise")-1, count))) {
+	} else if (sysfs_streq(buf, "madvise")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_FLAG, &transparent_hugepage_flags);
 		set_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flags);
-	} else if (!memcmp("never", buf,
-			   min(sizeof("never")-1, count))) {
+	} else if (sysfs_streq(buf, "never")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, &transparent_hugepage_flags);
 	} else
@@ -250,32 +247,27 @@ static ssize_t defrag_store(struct kobject *kobj,
 			    struct kobj_attribute *attr,
 			    const char *buf, size_t count)
 {
-	if (!memcmp("always", buf,
-		    min(sizeof("always")-1, count))) {
+	if (sysfs_streq(buf, "always")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, &transparent_hugepage_flags);
 		set_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags);
-	} else if (!memcmp("defer+madvise", buf,
-		    min(sizeof("defer+madvise")-1, count))) {
+	} else if (sysfs_streq(buf, "defer+madvise")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, &transparent_hugepage_flags);
 		set_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, &transparent_hugepage_flags);
-	} else if (!memcmp("defer", buf,
-		    min(sizeof("defer")-1, count))) {
+	} else if (sysfs_streq(buf, "defer")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, &transparent_hugepage_flags);
 		set_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, &transparent_hugepage_flags);
-	} else if (!memcmp("madvise", buf,
-			   min(sizeof("madvise")-1, count))) {
+	} else if (sysfs_streq(buf, "madvise")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, &transparent_hugepage_flags);
 		set_bit(TRANSPARENT_HUGEPAGE_DEFRAG_REQ_MADV_FLAG, &transparent_hugepage_flags);
-	} else if (!memcmp("never", buf,
-			   min(sizeof("never")-1, count))) {
+	} else if (sysfs_streq(buf, "never")) {
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_FLAG, &transparent_hugepage_flags);
 		clear_bit(TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG, &transparent_hugepage_flags);
@@ -527,6 +519,17 @@ void prep_transhuge_page(struct page *page)
 	set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);
 }
 
+bool is_transparent_hugepage(struct page *page)
+{
+	if (!PageCompound(page))
+		return 0;
+
+	page = compound_head(page);
+	return is_huge_zero_page(page) ||
+	       page[1].compound_dtor == TRANSHUGE_PAGE_DTOR;
+}
+EXPORT_SYMBOL_GPL(is_transparent_hugepage);
+
 static unsigned long __thp_get_unmapped_area(struct file *filp,
 		unsigned long addr, unsigned long len,
 		loff_t off, unsigned long flags, unsigned long size)
@@ -2704,7 +2707,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 {
 	struct page *head = compound_head(page);
 	struct pglist_data *pgdata = NODE_DATA(page_to_nid(head));
-	struct deferred_split *ds_queue = get_deferred_split_queue(page);
+	struct deferred_split *ds_queue = get_deferred_split_queue(head);
 	struct anon_vma *anon_vma = NULL;
 	struct address_space *mapping = NULL;
 	int count, mapcount, extra_pins, ret;
@@ -2712,11 +2715,11 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 	unsigned long flags;
 	pgoff_t end;
 
-	VM_BUG_ON_PAGE(is_huge_zero_page(page), page);
-	VM_BUG_ON_PAGE(!PageLocked(page), page);
-	VM_BUG_ON_PAGE(!PageCompound(page), page);
+	VM_BUG_ON_PAGE(is_huge_zero_page(head), head);
+	VM_BUG_ON_PAGE(!PageLocked(head), head);
+	VM_BUG_ON_PAGE(!PageCompound(head), head);
 
-	if (PageWriteback(page))
+	if (PageWriteback(head))
 		return -EBUSY;
 
 	if (PageAnon(head)) {
@@ -2767,7 +2770,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 		goto out_unlock;
 	}
 
-	mlocked = PageMlocked(page);
+	mlocked = PageMlocked(head);
 	unmap_page(head);
 	VM_BUG_ON_PAGE(compound_mapcount(head), head);
 
@@ -2799,14 +2802,14 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 			ds_queue->split_queue_len--;
 			list_del(page_deferred_list(head));
 		}
+		spin_unlock(&ds_queue->split_queue_lock);
 		if (mapping) {
-			if (PageSwapBacked(page))
-				__dec_node_page_state(page, NR_SHMEM_THPS);
+			if (PageSwapBacked(head))
+				__dec_node_page_state(head, NR_SHMEM_THPS);
 			else
-				__dec_node_page_state(page, NR_FILE_THPS);
+				__dec_node_page_state(head, NR_FILE_THPS);
 		}
 
-		spin_unlock(&ds_queue->split_queue_lock);
 		__split_huge_page(page, list, end, flags);
 		if (PageSwapCache(head)) {
 			swp_entry_t entry = { .val = page_private(head) };
diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
index 2ac38bdc18a1..e434b05416c6 100644
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -3,6 +3,10 @@
  * Copyright IBM Corporation, 2012
  * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
  *
+ * Cgroup v2
+ * Copyright (C) 2019 Red Hat, Inc.
+ * Author: Giuseppe Scrivano <gscrivan@redhat.com>
+ *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2.1 of the GNU Lesser General Public License
  * as published by the Free Software Foundation.
@@ -19,18 +23,36 @@
 #include <linux/hugetlb.h>
 #include <linux/hugetlb_cgroup.h>
 
+enum hugetlb_memory_event {
+	HUGETLB_MAX,
+	HUGETLB_NR_MEMORY_EVENTS,
+};
+
 struct hugetlb_cgroup {
 	struct cgroup_subsys_state css;
+
 	/*
 	 * the counter to account for hugepages from hugetlb.
 	 */
 	struct page_counter hugepage[HUGE_MAX_HSTATE];
+
+	atomic_long_t events[HUGE_MAX_HSTATE][HUGETLB_NR_MEMORY_EVENTS];
+	atomic_long_t events_local[HUGE_MAX_HSTATE][HUGETLB_NR_MEMORY_EVENTS];
+
+	/* Handle for "hugetlb.events" */
+	struct cgroup_file events_file[HUGE_MAX_HSTATE];
+
+	/* Handle for "hugetlb.events.local" */
+	struct cgroup_file events_local_file[HUGE_MAX_HSTATE];
 };
 
 #define MEMFILE_PRIVATE(x, val)	(((x) << 16) | (val))
 #define MEMFILE_IDX(val)	(((val) >> 16) & 0xffff)
 #define MEMFILE_ATTR(val)	((val) & 0xffff)
 
+#define hugetlb_cgroup_from_counter(counter, idx)                   \
+	container_of(counter, struct hugetlb_cgroup, hugepage[idx])
+
 static struct hugetlb_cgroup *root_h_cgroup __read_mostly;
 
 static inline
@@ -178,6 +200,19 @@ static void hugetlb_cgroup_css_offline(struct cgroup_subsys_state *css)
 	} while (hugetlb_cgroup_have_usage(h_cg));
 }
 
+static inline void hugetlb_event(struct hugetlb_cgroup *hugetlb, int idx,
+				 enum hugetlb_memory_event event)
+{
+	atomic_long_inc(&hugetlb->events_local[idx][event]);
+	cgroup_file_notify(&hugetlb->events_local_file[idx]);
+
+	do {
+		atomic_long_inc(&hugetlb->events[idx][event]);
+		cgroup_file_notify(&hugetlb->events_file[idx]);
+	} while ((hugetlb = parent_hugetlb_cgroup(hugetlb)) &&
+		 !hugetlb_cgroup_is_root(hugetlb));
+}
+
 int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
 				 struct hugetlb_cgroup **ptr)
 {
@@ -202,8 +237,12 @@ again:
 	}
 	rcu_read_unlock();
 
-	if (!page_counter_try_charge(&h_cg->hugepage[idx], nr_pages, &counter))
+	if (!page_counter_try_charge(&h_cg->hugepage[idx], nr_pages,
+				     &counter)) {
 		ret = -ENOMEM;
+		hugetlb_event(hugetlb_cgroup_from_counter(counter, idx), idx,
+			      HUGETLB_MAX);
+	}
 	css_put(&h_cg->css);
 done:
 	*ptr = h_cg;
@@ -283,10 +322,45 @@ static u64 hugetlb_cgroup_read_u64(struct cgroup_subsys_state *css,
 	}
 }
 
+static int hugetlb_cgroup_read_u64_max(struct seq_file *seq, void *v)
+{
+	int idx;
+	u64 val;
+	struct cftype *cft = seq_cft(seq);
+	unsigned long limit;
+	struct page_counter *counter;
+	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
+
+	idx = MEMFILE_IDX(cft->private);
+	counter = &h_cg->hugepage[idx];
+
+	limit = round_down(PAGE_COUNTER_MAX,
+			   1 << huge_page_order(&hstates[idx]));
+
+	switch (MEMFILE_ATTR(cft->private)) {
+	case RES_USAGE:
+		val = (u64)page_counter_read(counter);
+		seq_printf(seq, "%llu\n", val * PAGE_SIZE);
+		break;
+	case RES_LIMIT:
+		val = (u64)counter->max;
+		if (val == limit)
+			seq_puts(seq, "max\n");
+		else
+			seq_printf(seq, "%llu\n", val * PAGE_SIZE);
+		break;
+	default:
+		BUG();
+	}
+
+	return 0;
+}
+
 static DEFINE_MUTEX(hugetlb_limit_mutex);
 
 static ssize_t hugetlb_cgroup_write(struct kernfs_open_file *of,
-				    char *buf, size_t nbytes, loff_t off)
+				    char *buf, size_t nbytes, loff_t off,
+				    const char *max)
 {
 	int ret, idx;
 	unsigned long nr_pages;
@@ -296,7 +370,7 @@ static ssize_t hugetlb_cgroup_write(struct kernfs_open_file *of,
 		return -EINVAL;
 
 	buf = strstrip(buf);
-	ret = page_counter_memparse(buf, "-1", &nr_pages);
+	ret = page_counter_memparse(buf, max, &nr_pages);
 	if (ret)
 		return ret;
 
@@ -316,6 +390,18 @@ static ssize_t hugetlb_cgroup_write(struct kernfs_open_file *of,
 	return ret ?: nbytes;
 }
 
+static ssize_t hugetlb_cgroup_write_legacy(struct kernfs_open_file *of,
+					   char *buf, size_t nbytes, loff_t off)
+{
+	return hugetlb_cgroup_write(of, buf, nbytes, off, "-1");
+}
+
+static ssize_t hugetlb_cgroup_write_dfl(struct kernfs_open_file *of,
+					char *buf, size_t nbytes, loff_t off)
+{
+	return hugetlb_cgroup_write(of, buf, nbytes, off, "max");
+}
+
 static ssize_t hugetlb_cgroup_reset(struct kernfs_open_file *of,
 				    char *buf, size_t nbytes, loff_t off)
 {
@@ -350,7 +436,36 @@ static char *mem_fmt(char *buf, int size, unsigned long hsize)
 	return buf;
 }
 
-static void __init __hugetlb_cgroup_file_init(int idx)
+static int __hugetlb_events_show(struct seq_file *seq, bool local)
+{
+	int idx;
+	long max;
+	struct cftype *cft = seq_cft(seq);
+	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
+
+	idx = MEMFILE_IDX(cft->private);
+
+	if (local)
+		max = atomic_long_read(&h_cg->events_local[idx][HUGETLB_MAX]);
+	else
+		max = atomic_long_read(&h_cg->events[idx][HUGETLB_MAX]);
+
+	seq_printf(seq, "max %lu\n", max);
+
+	return 0;
+}
+
+static int hugetlb_events_show(struct seq_file *seq, void *v)
+{
+	return __hugetlb_events_show(seq, false);
+}
+
+static int hugetlb_events_local_show(struct seq_file *seq, void *v)
+{
+	return __hugetlb_events_show(seq, true);
+}
+
+static void __init __hugetlb_cgroup_file_dfl_init(int idx)
 {
 	char buf[32];
 	struct cftype *cft;
@@ -360,38 +475,93 @@ static void __init __hugetlb_cgroup_file_init(int idx)
 	mem_fmt(buf, 32, huge_page_size(h));
 
 	/* Add the limit file */
-	cft = &h->cgroup_files[0];
+	cft = &h->cgroup_files_dfl[0];
+	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max", buf);
+	cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
+	cft->seq_show = hugetlb_cgroup_read_u64_max;
+	cft->write = hugetlb_cgroup_write_dfl;
+	cft->flags = CFTYPE_NOT_ON_ROOT;
+
+	/* Add the current usage file */
+	cft = &h->cgroup_files_dfl[1];
+	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.current", buf);
+	cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
+	cft->seq_show = hugetlb_cgroup_read_u64_max;
+	cft->flags = CFTYPE_NOT_ON_ROOT;
+
+	/* Add the events file */
+	cft = &h->cgroup_files_dfl[2];
+	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.events", buf);
+	cft->private = MEMFILE_PRIVATE(idx, 0);
+	cft->seq_show = hugetlb_events_show;
+	cft->file_offset = offsetof(struct hugetlb_cgroup, events_file[idx]),
+	cft->flags = CFTYPE_NOT_ON_ROOT;
+
+	/* Add the events.local file */
+	cft = &h->cgroup_files_dfl[3];
+	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.events.local", buf);
+	cft->private = MEMFILE_PRIVATE(idx, 0);
+	cft->seq_show = hugetlb_events_local_show;
+	cft->file_offset = offsetof(struct hugetlb_cgroup,
+				    events_local_file[idx]),
+	cft->flags = CFTYPE_NOT_ON_ROOT;
+
+	/* NULL terminate the last cft */
+	cft = &h->cgroup_files_dfl[4];
+	memset(cft, 0, sizeof(*cft));
+
+	WARN_ON(cgroup_add_dfl_cftypes(&hugetlb_cgrp_subsys,
+				       h->cgroup_files_dfl));
+}
+
+static void __init __hugetlb_cgroup_file_legacy_init(int idx)
+{
+	char buf[32];
+	struct cftype *cft;
+	struct hstate *h = &hstates[idx];
+
+	/* format the size */
+	mem_fmt(buf, 32, huge_page_size(h));
+
+	/* Add the limit file */
+	cft = &h->cgroup_files_legacy[0];
 	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.limit_in_bytes", buf);
 	cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
 	cft->read_u64 = hugetlb_cgroup_read_u64;
-	cft->write = hugetlb_cgroup_write;
+	cft->write = hugetlb_cgroup_write_legacy;
 
 	/* Add the usage file */
-	cft = &h->cgroup_files[1];
+	cft = &h->cgroup_files_legacy[1];
 	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.usage_in_bytes", buf);
 	cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
 	cft->read_u64 = hugetlb_cgroup_read_u64;
 
 	/* Add the MAX usage file */
-	cft = &h->cgroup_files[2];
+	cft = &h->cgroup_files_legacy[2];
 	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max_usage_in_bytes", buf);
 	cft->private = MEMFILE_PRIVATE(idx, RES_MAX_USAGE);
 	cft->write = hugetlb_cgroup_reset;
 	cft->read_u64 = hugetlb_cgroup_read_u64;
 
 	/* Add the failcntfile */
-	cft = &h->cgroup_files[3];
+	cft = &h->cgroup_files_legacy[3];
 	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.failcnt", buf);
 	cft->private  = MEMFILE_PRIVATE(idx, RES_FAILCNT);
 	cft->write = hugetlb_cgroup_reset;
 	cft->read_u64 = hugetlb_cgroup_read_u64;
 
 	/* NULL terminate the last cft */
-	cft = &h->cgroup_files[4];
+	cft = &h->cgroup_files_legacy[4];
 	memset(cft, 0, sizeof(*cft));
 
 	WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys,
-					  h->cgroup_files));
+					  h->cgroup_files_legacy));
+}
+
+static void __init __hugetlb_cgroup_file_init(int idx)
+{
+	__hugetlb_cgroup_file_dfl_init(idx);
+	__hugetlb_cgroup_file_legacy_init(idx);
 }
 
 void __init hugetlb_cgroup_file_init(void)
@@ -433,8 +603,14 @@ void hugetlb_cgroup_migrate(struct page *oldhpage, struct page *newhpage)
 	return;
 }
 
+static struct cftype hugetlb_files[] = {
+	{} /* terminate */
+};
+
 struct cgroup_subsys hugetlb_cgrp_subsys = {
 	.css_alloc	= hugetlb_cgroup_css_alloc,
 	.css_offline	= hugetlb_cgroup_css_offline,
 	.css_free	= hugetlb_cgroup_css_free,
+	.dfl_cftypes	= hugetlb_files,
+	.legacy_cftypes	= hugetlb_files,
 };
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index c15d8ae68c96..6aa51723b92b 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -110,6 +110,7 @@ void *memset(void *addr, int c, size_t len)
 	return __memset(addr, c, len);
 }
 
+#ifdef __HAVE_ARCH_MEMMOVE
 #undef memmove
 void *memmove(void *dest, const void *src, size_t len)
 {
@@ -118,6 +119,7 @@ void *memmove(void *dest, const void *src, size_t len)
 
 	return __memmove(dest, src, len);
 }
+#endif
 
 #undef memcpy
 void *memcpy(void *dest, const void *src, size_t len)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 621782100eaa..5ef9f24f566b 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -512,3 +512,43 @@ void __kasan_report(unsigned long addr, size_t size, bool is_write, unsigned lon
 
 	end_report(&flags);
 }
+
+#ifdef CONFIG_KASAN_INLINE
+/*
+ * With CONFIG_KASAN_INLINE, accesses to bogus pointers (outside the high
+ * canonical half of the address space) cause out-of-bounds shadow memory reads
+ * before the actual access. For addresses in the low canonical half of the
+ * address space, as well as most non-canonical addresses, that out-of-bounds
+ * shadow memory access lands in the non-canonical part of the address space.
+ * Help the user figure out what the original bogus pointer was.
+ */
+void kasan_non_canonical_hook(unsigned long addr)
+{
+	unsigned long orig_addr;
+	const char *bug_type;
+
+	if (addr < KASAN_SHADOW_OFFSET)
+		return;
+
+	orig_addr = (addr - KASAN_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT;
+	/*
+	 * For faults near the shadow address for NULL, we can be fairly certain
+	 * that this is a KASAN shadow memory access.
+	 * For faults that correspond to shadow for low canonical addresses, we
+	 * can still be pretty sure - that shadow region is a fairly narrow
+	 * chunk of the non-canonical address space.
+	 * But faults that look like shadow for non-canonical addresses are a
+	 * really large chunk of the address space. In that case, we still
+	 * print the decoded address, but make it clear that this is not
+	 * necessarily what's actually going on.
+	 */
+	if (orig_addr < PAGE_SIZE)
+		bug_type = "null-ptr-deref";
+	else if (orig_addr < TASK_SIZE)
+		bug_type = "probably user-memory-access";
+	else
+		bug_type = "maybe wild-memory-access";
+	pr_alert("KASAN: %s in range [0x%016lx-0x%016lx]\n", bug_type,
+		 orig_addr, orig_addr + KASAN_SHADOW_MASK);
+}
+#endif
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 244607663363..3a4259eeb5a0 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -13,7 +13,7 @@
  *
  * The following locks and mutexes are used by kmemleak:
  *
- * - kmemleak_lock (rwlock): protects the object_list modifications and
+ * - kmemleak_lock (raw_spinlock_t): protects the object_list modifications and
  *   accesses to the object_tree_root. The object_list is the main list
  *   holding the metadata (struct kmemleak_object) for the allocated memory
  *   blocks. The object_tree_root is a red black tree used to look-up
@@ -22,13 +22,13 @@
  *   object_tree_root in the create_object() function called from the
  *   kmemleak_alloc() callback and removed in delete_object() called from the
  *   kmemleak_free() callback
- * - kmemleak_object.lock (spinlock): protects a kmemleak_object. Accesses to
- *   the metadata (e.g. count) are protected by this lock. Note that some
- *   members of this structure may be protected by other means (atomic or
- *   kmemleak_lock). This lock is also held when scanning the corresponding
- *   memory block to avoid the kernel freeing it via the kmemleak_free()
- *   callback. This is less heavyweight than holding a global lock like
- *   kmemleak_lock during scanning
+ * - kmemleak_object.lock (raw_spinlock_t): protects a kmemleak_object.
+ *   Accesses to the metadata (e.g. count) are protected by this lock. Note
+ *   that some members of this structure may be protected by other means
+ *   (atomic or kmemleak_lock). This lock is also held when scanning the
+ *   corresponding memory block to avoid the kernel freeing it via the
+ *   kmemleak_free() callback. This is less heavyweight than holding a global
+ *   lock like kmemleak_lock during scanning.
  * - scan_mutex (mutex): ensures that only one thread may scan the memory for
  *   unreferenced objects at a time. The gray_list contains the objects which
  *   are already referenced or marked as false positives and need to be
@@ -135,7 +135,7 @@ struct kmemleak_scan_area {
  * (use_count) and freed using the RCU mechanism.
  */
 struct kmemleak_object {
-	spinlock_t lock;
+	raw_spinlock_t lock;
 	unsigned int flags;		/* object status flags */
 	struct list_head object_list;
 	struct list_head gray_list;
@@ -191,8 +191,8 @@ static int mem_pool_free_count = ARRAY_SIZE(mem_pool);
 static LIST_HEAD(mem_pool_free_list);
 /* search tree for object boundaries */
 static struct rb_root object_tree_root = RB_ROOT;
-/* rw_lock protecting the access to object_list and object_tree_root */
-static DEFINE_RWLOCK(kmemleak_lock);
+/* protecting the access to object_list and object_tree_root */
+static DEFINE_RAW_SPINLOCK(kmemleak_lock);
 
 /* allocation caches for kmemleak internal data */
 static struct kmem_cache *object_cache;
@@ -426,7 +426,7 @@ static struct kmemleak_object *mem_pool_alloc(gfp_t gfp)
 	}
 
 	/* slab allocation failed, try the memory pool */
-	write_lock_irqsave(&kmemleak_lock, flags);
+	raw_spin_lock_irqsave(&kmemleak_lock, flags);
 	object = list_first_entry_or_null(&mem_pool_free_list,
 					  typeof(*object), object_list);
 	if (object)
@@ -435,7 +435,7 @@ static struct kmemleak_object *mem_pool_alloc(gfp_t gfp)
 		object = &mem_pool[--mem_pool_free_count];
 	else
 		pr_warn_once("Memory pool empty, consider increasing CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE\n");
-	write_unlock_irqrestore(&kmemleak_lock, flags);
+	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
 
 	return object;
 }
@@ -453,9 +453,9 @@ static void mem_pool_free(struct kmemleak_object *object)
 	}
 
 	/* add the object to the memory pool free list */
-	write_lock_irqsave(&kmemleak_lock, flags);
+	raw_spin_lock_irqsave(&kmemleak_lock, flags);
 	list_add(&object->object_list, &mem_pool_free_list);
-	write_unlock_irqrestore(&kmemleak_lock, flags);
+	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
 }
 
 /*
@@ -514,9 +514,9 @@ static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias)
 	struct kmemleak_object *object;
 
 	rcu_read_lock();
-	read_lock_irqsave(&kmemleak_lock, flags);
+	raw_spin_lock_irqsave(&kmemleak_lock, flags);
 	object = lookup_object(ptr, alias);
-	read_unlock_irqrestore(&kmemleak_lock, flags);
+	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
 
 	/* check whether the object is still available */
 	if (object && !get_object(object))
@@ -546,11 +546,11 @@ static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int ali
 	unsigned long flags;
 	struct kmemleak_object *object;
 
-	write_lock_irqsave(&kmemleak_lock, flags);
+	raw_spin_lock_irqsave(&kmemleak_lock, flags);
 	object = lookup_object(ptr, alias);
 	if (object)
 		__remove_object(object);
-	write_unlock_irqrestore(&kmemleak_lock, flags);
+	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
 
 	return object;
 }
@@ -585,7 +585,7 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
 	INIT_LIST_HEAD(&object->object_list);
 	INIT_LIST_HEAD(&object->gray_list);
 	INIT_HLIST_HEAD(&object->area_list);
-	spin_lock_init(&object->lock);
+	raw_spin_lock_init(&object->lock);
 	atomic_set(&object->use_count, 1);
 	object->flags = OBJECT_ALLOCATED;
 	object->pointer = ptr;
@@ -617,7 +617,7 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
 	/* kernel backtrace */
 	object->trace_len = __save_stack_trace(object->trace);
 
-	write_lock_irqsave(&kmemleak_lock, flags);
+	raw_spin_lock_irqsave(&kmemleak_lock, flags);
 
 	untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr);
 	min_addr = min(min_addr, untagged_ptr);
@@ -649,7 +649,7 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
 
 	list_add_tail_rcu(&object->object_list, &object_list);
 out:
-	write_unlock_irqrestore(&kmemleak_lock, flags);
+	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
 	return object;
 }
 
@@ -667,9 +667,9 @@ static void __delete_object(struct kmemleak_object *object)
 	 * Locking here also ensures that the corresponding memory block
 	 * cannot be freed when it is being scanned.
 	 */
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	object->flags &= ~OBJECT_ALLOCATED;
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 	put_object(object);
 }
 
@@ -739,9 +739,9 @@ static void paint_it(struct kmemleak_object *object, int color)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	__paint_it(object, color);
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 }
 
 static void paint_ptr(unsigned long ptr, int color)
@@ -798,7 +798,7 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp)
 	if (scan_area_cache)
 		area = kmem_cache_alloc(scan_area_cache, gfp_kmemleak_mask(gfp));
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	if (!area) {
 		pr_warn_once("Cannot allocate a scan area, scanning the full object\n");
 		/* mark the object for full scan to avoid false positives */
@@ -820,7 +820,7 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp)
 
 	hlist_add_head(&area->node, &object->area_list);
 out_unlock:
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 	put_object(object);
 }
 
@@ -842,9 +842,9 @@ static void object_set_excess_ref(unsigned long ptr, unsigned long excess_ref)
 		return;
 	}
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	object->excess_ref = excess_ref;
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 	put_object(object);
 }
 
@@ -864,9 +864,9 @@ static void object_no_scan(unsigned long ptr)
 		return;
 	}
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	object->flags |= OBJECT_NO_SCAN;
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 	put_object(object);
 }
 
@@ -1026,9 +1026,9 @@ void __ref kmemleak_update_trace(const void *ptr)
 		return;
 	}
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	object->trace_len = __save_stack_trace(object->trace);
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 
 	put_object(object);
 }
@@ -1233,7 +1233,7 @@ static void scan_block(void *_start, void *_end,
 	unsigned long flags;
 	unsigned long untagged_ptr;
 
-	read_lock_irqsave(&kmemleak_lock, flags);
+	raw_spin_lock_irqsave(&kmemleak_lock, flags);
 	for (ptr = start; ptr < end; ptr++) {
 		struct kmemleak_object *object;
 		unsigned long pointer;
@@ -1268,7 +1268,7 @@ static void scan_block(void *_start, void *_end,
 		 * previously acquired in scan_object(). These locks are
 		 * enclosed by scan_mutex.
 		 */
-		spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
+		raw_spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
 		/* only pass surplus references (object already gray) */
 		if (color_gray(object)) {
 			excess_ref = object->excess_ref;
@@ -1277,7 +1277,7 @@ static void scan_block(void *_start, void *_end,
 			excess_ref = 0;
 			update_refs(object);
 		}
-		spin_unlock(&object->lock);
+		raw_spin_unlock(&object->lock);
 
 		if (excess_ref) {
 			object = lookup_object(excess_ref, 0);
@@ -1286,12 +1286,12 @@ static void scan_block(void *_start, void *_end,
 			if (object == scanned)
 				/* circular reference, ignore */
 				continue;
-			spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
+			raw_spin_lock_nested(&object->lock, SINGLE_DEPTH_NESTING);
 			update_refs(object);
-			spin_unlock(&object->lock);
+			raw_spin_unlock(&object->lock);
 		}
 	}
-	read_unlock_irqrestore(&kmemleak_lock, flags);
+	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
 }
 
 /*
@@ -1324,7 +1324,7 @@ static void scan_object(struct kmemleak_object *object)
 	 * Once the object->lock is acquired, the corresponding memory block
 	 * cannot be freed (the same lock is acquired in delete_object).
 	 */
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	if (object->flags & OBJECT_NO_SCAN)
 		goto out;
 	if (!(object->flags & OBJECT_ALLOCATED))
@@ -1344,9 +1344,9 @@ static void scan_object(struct kmemleak_object *object)
 			if (start >= end)
 				break;
 
-			spin_unlock_irqrestore(&object->lock, flags);
+			raw_spin_unlock_irqrestore(&object->lock, flags);
 			cond_resched();
-			spin_lock_irqsave(&object->lock, flags);
+			raw_spin_lock_irqsave(&object->lock, flags);
 		} while (object->flags & OBJECT_ALLOCATED);
 	} else
 		hlist_for_each_entry(area, &object->area_list, node)
@@ -1354,7 +1354,7 @@ static void scan_object(struct kmemleak_object *object)
 				   (void *)(area->start + area->size),
 				   object);
 out:
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 }
 
 /*
@@ -1407,7 +1407,7 @@ static void kmemleak_scan(void)
 	/* prepare the kmemleak_object's */
 	rcu_read_lock();
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		spin_lock_irqsave(&object->lock, flags);
+		raw_spin_lock_irqsave(&object->lock, flags);
 #ifdef DEBUG
 		/*
 		 * With a few exceptions there should be a maximum of
@@ -1424,7 +1424,7 @@ static void kmemleak_scan(void)
 		if (color_gray(object) && get_object(object))
 			list_add_tail(&object->gray_list, &gray_list);
 
-		spin_unlock_irqrestore(&object->lock, flags);
+		raw_spin_unlock_irqrestore(&object->lock, flags);
 	}
 	rcu_read_unlock();
 
@@ -1492,14 +1492,14 @@ static void kmemleak_scan(void)
 	 */
 	rcu_read_lock();
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		spin_lock_irqsave(&object->lock, flags);
+		raw_spin_lock_irqsave(&object->lock, flags);
 		if (color_white(object) && (object->flags & OBJECT_ALLOCATED)
 		    && update_checksum(object) && get_object(object)) {
 			/* color it gray temporarily */
 			object->count = object->min_count;
 			list_add_tail(&object->gray_list, &gray_list);
 		}
-		spin_unlock_irqrestore(&object->lock, flags);
+		raw_spin_unlock_irqrestore(&object->lock, flags);
 	}
 	rcu_read_unlock();
 
@@ -1519,7 +1519,7 @@ static void kmemleak_scan(void)
 	 */
 	rcu_read_lock();
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		spin_lock_irqsave(&object->lock, flags);
+		raw_spin_lock_irqsave(&object->lock, flags);
 		if (unreferenced_object(object) &&
 		    !(object->flags & OBJECT_REPORTED)) {
 			object->flags |= OBJECT_REPORTED;
@@ -1529,7 +1529,7 @@ static void kmemleak_scan(void)
 
 			new_leaks++;
 		}
-		spin_unlock_irqrestore(&object->lock, flags);
+		raw_spin_unlock_irqrestore(&object->lock, flags);
 	}
 	rcu_read_unlock();
 
@@ -1681,10 +1681,10 @@ static int kmemleak_seq_show(struct seq_file *seq, void *v)
 	struct kmemleak_object *object = v;
 	unsigned long flags;
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	if ((object->flags & OBJECT_REPORTED) && unreferenced_object(object))
 		print_unreferenced(seq, object);
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 	return 0;
 }
 
@@ -1714,9 +1714,9 @@ static int dump_str_object_info(const char *str)
 		return -EINVAL;
 	}
 
-	spin_lock_irqsave(&object->lock, flags);
+	raw_spin_lock_irqsave(&object->lock, flags);
 	dump_object_info(object);
-	spin_unlock_irqrestore(&object->lock, flags);
+	raw_spin_unlock_irqrestore(&object->lock, flags);
 
 	put_object(object);
 	return 0;
@@ -1735,11 +1735,11 @@ static void kmemleak_clear(void)
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(object, &object_list, object_list) {
-		spin_lock_irqsave(&object->lock, flags);
+		raw_spin_lock_irqsave(&object->lock, flags);
 		if ((object->flags & OBJECT_REPORTED) &&
 		    unreferenced_object(object))
 			__paint_it(object, KMEMLEAK_GREY);
-		spin_unlock_irqrestore(&object->lock, flags);
+		raw_spin_unlock_irqrestore(&object->lock, flags);
 	}
 	rcu_read_unlock();
 
diff --git a/mm/madvise.c b/mm/madvise.c
index bcdb6a042787..43b47d3fae02 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -1044,7 +1044,7 @@ madvise_behavior_valid(int behavior)
  *  -EBADF  - map exists, but area maps something that isn't a file.
  *  -EAGAIN - a kernel resource was temporarily unavailable.
  */
-SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
+int do_madvise(unsigned long start, size_t len_in, int behavior)
 {
 	unsigned long end, tmp;
 	struct vm_area_struct *vma, *prev;
@@ -1141,3 +1141,8 @@ out:
 
 	return error;
 }
+
+SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
+{
+	return do_madvise(start, len_in, behavior);
+}
diff --git a/mm/memblock.c b/mm/memblock.c
index 4bc2c7d8bf42..eba94ee3de0b 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -575,7 +575,7 @@ static void __init_memblock memblock_insert_region(struct memblock_type *type,
  * Return:
  * 0 on success, -errno on failure.
  */
-int __init_memblock memblock_add_range(struct memblock_type *type,
+static int __init_memblock memblock_add_range(struct memblock_type *type,
 				phys_addr_t base, phys_addr_t size,
 				int nid, enum memblock_flags flags)
 {
@@ -694,7 +694,7 @@ int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
 {
 	phys_addr_t end = base + size - 1;
 
-	memblock_dbg("memblock_add: [%pa-%pa] %pS\n",
+	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
 		     &base, &end, (void *)_RET_IP_);
 
 	return memblock_add_range(&memblock.memory, base, size, MAX_NUMNODES, 0);
@@ -795,7 +795,7 @@ int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
 {
 	phys_addr_t end = base + size - 1;
 
-	memblock_dbg("memblock_remove: [%pa-%pa] %pS\n",
+	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
 		     &base, &end, (void *)_RET_IP_);
 
 	return memblock_remove_range(&memblock.memory, base, size);
@@ -813,7 +813,7 @@ int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
 {
 	phys_addr_t end = base + size - 1;
 
-	memblock_dbg("   memblock_free: [%pa-%pa] %pS\n",
+	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
 		     &base, &end, (void *)_RET_IP_);
 
 	kmemleak_free_part_phys(base, size);
@@ -824,12 +824,24 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
 {
 	phys_addr_t end = base + size - 1;
 
-	memblock_dbg("memblock_reserve: [%pa-%pa] %pS\n",
+	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
 		     &base, &end, (void *)_RET_IP_);
 
 	return memblock_add_range(&memblock.reserved, base, size, MAX_NUMNODES, 0);
 }
 
+#ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
+int __init_memblock memblock_physmem_add(phys_addr_t base, phys_addr_t size)
+{
+	phys_addr_t end = base + size - 1;
+
+	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
+		     &base, &end, (void *)_RET_IP_);
+
+	return memblock_add_range(&memblock.physmem, base, size, MAX_NUMNODES, 0);
+}
+#endif
+
 /**
  * memblock_setclr_flag - set or clear flag for a memory region
  * @base: base address of the region
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6c83cf4ed970..d09776cd6e10 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -409,8 +409,10 @@ int memcg_expand_shrinker_maps(int new_id)
 		if (mem_cgroup_is_root(memcg))
 			continue;
 		ret = memcg_expand_one_shrinker_map(memcg, size, old_size);
-		if (ret)
+		if (ret) {
+			mem_cgroup_iter_break(NULL, memcg);
 			goto unlock;
+		}
 	}
 unlock:
 	if (!ret)
@@ -5340,14 +5342,6 @@ static int mem_cgroup_move_account(struct page *page,
 		__mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages);
 	}
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	if (compound && !list_empty(page_deferred_list(page))) {
-		spin_lock(&from->deferred_split_queue.split_queue_lock);
-		list_del_init(page_deferred_list(page));
-		from->deferred_split_queue.split_queue_len--;
-		spin_unlock(&from->deferred_split_queue.split_queue_lock);
-	}
-#endif
 	/*
 	 * It is safe to change page->mem_cgroup here because the page
 	 * is referenced, charged, and isolated - we can't race with
@@ -5357,16 +5351,6 @@ static int mem_cgroup_move_account(struct page *page,
 	/* caller should have done css_get */
 	page->mem_cgroup = to;
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	if (compound && list_empty(page_deferred_list(page))) {
-		spin_lock(&to->deferred_split_queue.split_queue_lock);
-		list_add_tail(page_deferred_list(page),
-			      &to->deferred_split_queue.split_queue);
-		to->deferred_split_queue.split_queue_len++;
-		spin_unlock(&to->deferred_split_queue.split_queue_lock);
-	}
-#endif
-
 	spin_unlock_irqrestore(&from->move_lock, flags);
 
 	ret = 0;
@@ -6651,7 +6635,6 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 {
 	struct mem_cgroup *memcg;
 	unsigned int nr_pages;
-	bool compound;
 	unsigned long flags;
 
 	VM_BUG_ON_PAGE(!PageLocked(oldpage), oldpage);
@@ -6673,8 +6656,7 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 		return;
 
 	/* Force-charge the new page. The old one will be freed soon */
-	compound = PageTransHuge(newpage);
-	nr_pages = compound ? hpage_nr_pages(newpage) : 1;
+	nr_pages = hpage_nr_pages(newpage);
 
 	page_counter_charge(&memcg->memory, nr_pages);
 	if (do_memsw_account())
@@ -6684,7 +6666,8 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 	commit_charge(newpage, memcg, false);
 
 	local_irq_save(flags);
-	mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages);
+	mem_cgroup_charge_statistics(memcg, newpage, PageTransHuge(newpage),
+			nr_pages);
 	memcg_check_events(memcg, newpage);
 	local_irq_restore(flags);
 }
diff --git a/mm/memory.c b/mm/memory.c
index 45442d9a4f52..0bccc622e482 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1664,6 +1664,9 @@ out_unlock:
  * vmf_insert_pfn_prot should only be used if using multiple VMAs is
  * impractical.
  *
+ * See vmf_insert_mixed_prot() for a discussion of the implication of using
+ * a value of @pgprot different from that of @vma->vm_page_prot.
+ *
  * Context: Process context.  May allocate using %GFP_KERNEL.
  * Return: vm_fault_t value.
  */
@@ -1737,9 +1740,9 @@ static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn)
 }
 
 static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma,
-		unsigned long addr, pfn_t pfn, bool mkwrite)
+		unsigned long addr, pfn_t pfn, pgprot_t pgprot,
+		bool mkwrite)
 {
-	pgprot_t pgprot = vma->vm_page_prot;
 	int err;
 
 	BUG_ON(!vm_mixed_ok(vma, pfn));
@@ -1782,10 +1785,43 @@ static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma,
 	return VM_FAULT_NOPAGE;
 }
 
+/**
+ * vmf_insert_mixed_prot - insert single pfn into user vma with specified pgprot
+ * @vma: user vma to map to
+ * @addr: target user address of this page
+ * @pfn: source kernel pfn
+ * @pgprot: pgprot flags for the inserted page
+ *
+ * This is exactly like vmf_insert_mixed(), except that it allows drivers to
+ * to override pgprot on a per-page basis.
+ *
+ * Typically this function should be used by drivers to set caching- and
+ * encryption bits different than those of @vma->vm_page_prot, because
+ * the caching- or encryption mode may not be known at mmap() time.
+ * This is ok as long as @vma->vm_page_prot is not used by the core vm
+ * to set caching and encryption bits for those vmas (except for COW pages).
+ * This is ensured by core vm only modifying these page table entries using
+ * functions that don't touch caching- or encryption bits, using pte_modify()
+ * if needed. (See for example mprotect()).
+ * Also when new page-table entries are created, this is only done using the
+ * fault() callback, and never using the value of vma->vm_page_prot,
+ * except for page-table entries that point to anonymous pages as the result
+ * of COW.
+ *
+ * Context: Process context.  May allocate using %GFP_KERNEL.
+ * Return: vm_fault_t value.
+ */
+vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr,
+				 pfn_t pfn, pgprot_t pgprot)
+{
+	return __vm_insert_mixed(vma, addr, pfn, pgprot, false);
+}
+EXPORT_SYMBOL(vmf_insert_mixed_prot);
+
 vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
 		pfn_t pfn)
 {
-	return __vm_insert_mixed(vma, addr, pfn, false);
+	return __vm_insert_mixed(vma, addr, pfn, vma->vm_page_prot, false);
 }
 EXPORT_SYMBOL(vmf_insert_mixed);
 
@@ -1797,7 +1833,7 @@ EXPORT_SYMBOL(vmf_insert_mixed);
 vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
 		unsigned long addr, pfn_t pfn)
 {
-	return __vm_insert_mixed(vma, addr, pfn, true);
+	return __vm_insert_mixed(vma, addr, pfn, vma->vm_page_prot, true);
 }
 EXPORT_SYMBOL(vmf_insert_mixed_mkwrite);
 
@@ -2203,7 +2239,7 @@ static inline int pte_unmap_same(struct mm_struct *mm, pmd_t *pmd,
 				pte_t *page_table, pte_t orig_pte)
 {
 	int same = 1;
-#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPTION)
 	if (sizeof(pte_t) > sizeof(unsigned long)) {
 		spinlock_t *ptl = pte_lockptr(mm, pmd);
 		spin_lock(ptl);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index a91a072f2b2c..0a54ffac8c68 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -355,7 +355,7 @@ static unsigned long find_smallest_section_pfn(int nid, struct zone *zone,
 		if (unlikely(pfn_to_nid(start_pfn) != nid))
 			continue;
 
-		if (zone && zone != page_zone(pfn_to_page(start_pfn)))
+		if (zone != page_zone(pfn_to_page(start_pfn)))
 			continue;
 
 		return start_pfn;
@@ -380,7 +380,7 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone,
 		if (unlikely(pfn_to_nid(pfn) != nid))
 			continue;
 
-		if (zone && zone != page_zone(pfn_to_page(pfn)))
+		if (zone != page_zone(pfn_to_page(pfn)))
 			continue;
 
 		return pfn;
@@ -392,14 +392,11 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone,
 static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
 			     unsigned long end_pfn)
 {
-	unsigned long zone_start_pfn = zone->zone_start_pfn;
-	unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */
-	unsigned long zone_end_pfn = z;
 	unsigned long pfn;
 	int nid = zone_to_nid(zone);
 
 	zone_span_writelock(zone);
-	if (zone_start_pfn == start_pfn) {
+	if (zone->zone_start_pfn == start_pfn) {
 		/*
 		 * If the section is smallest section in the zone, it need
 		 * shrink zone->zone_start_pfn and zone->zone_spanned_pages.
@@ -407,50 +404,30 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
 		 * for shrinking zone.
 		 */
 		pfn = find_smallest_section_pfn(nid, zone, end_pfn,
-						zone_end_pfn);
+						zone_end_pfn(zone));
 		if (pfn) {
+			zone->spanned_pages = zone_end_pfn(zone) - pfn;
 			zone->zone_start_pfn = pfn;
-			zone->spanned_pages = zone_end_pfn - pfn;
+		} else {
+			zone->zone_start_pfn = 0;
+			zone->spanned_pages = 0;
 		}
-	} else if (zone_end_pfn == end_pfn) {
+	} else if (zone_end_pfn(zone) == end_pfn) {
 		/*
 		 * If the section is biggest section in the zone, it need
 		 * shrink zone->spanned_pages.
 		 * In this case, we find second biggest valid mem_section for
 		 * shrinking zone.
 		 */
-		pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
+		pfn = find_biggest_section_pfn(nid, zone, zone->zone_start_pfn,
 					       start_pfn);
 		if (pfn)
-			zone->spanned_pages = pfn - zone_start_pfn + 1;
-	}
-
-	/*
-	 * The section is not biggest or smallest mem_section in the zone, it
-	 * only creates a hole in the zone. So in this case, we need not
-	 * change the zone. But perhaps, the zone has only hole data. Thus
-	 * it check the zone has only hole or not.
-	 */
-	pfn = zone_start_pfn;
-	for (; pfn < zone_end_pfn; pfn += PAGES_PER_SUBSECTION) {
-		if (unlikely(!pfn_to_online_page(pfn)))
-			continue;
-
-		if (page_zone(pfn_to_page(pfn)) != zone)
-			continue;
-
-		/* Skip range to be removed */
-		if (pfn >= start_pfn && pfn < end_pfn)
-			continue;
-
-		/* If we find valid section, we have nothing to do */
-		zone_span_writeunlock(zone);
-		return;
+			zone->spanned_pages = pfn - zone->zone_start_pfn + 1;
+		else {
+			zone->zone_start_pfn = 0;
+			zone->spanned_pages = 0;
+		}
 	}
-
-	/* The zone has no valid section */
-	zone->zone_start_pfn = 0;
-	zone->spanned_pages = 0;
 	zone_span_writeunlock(zone);
 }
 
@@ -490,6 +467,9 @@ void __ref remove_pfn_range_from_zone(struct zone *zone,
 	struct pglist_data *pgdat = zone->zone_pgdat;
 	unsigned long flags;
 
+	/* Poison struct pages because they are now uninitialized again. */
+	page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * nr_pages);
+
 #ifdef CONFIG_ZONE_DEVICE
 	/*
 	 * Zone shrinking code cannot properly deal with ZONE_DEVICE. So
@@ -536,25 +516,20 @@ static void __remove_section(unsigned long pfn, unsigned long nr_pages,
 void __remove_pages(unsigned long pfn, unsigned long nr_pages,
 		    struct vmem_altmap *altmap)
 {
+	const unsigned long end_pfn = pfn + nr_pages;
+	unsigned long cur_nr_pages;
 	unsigned long map_offset = 0;
-	unsigned long nr, start_sec, end_sec;
 
 	map_offset = vmem_altmap_offset(altmap);
 
 	if (check_pfn_span(pfn, nr_pages, "remove"))
 		return;
 
-	start_sec = pfn_to_section_nr(pfn);
-	end_sec = pfn_to_section_nr(pfn + nr_pages - 1);
-	for (nr = start_sec; nr <= end_sec; nr++) {
-		unsigned long pfns;
-
+	for (; pfn < end_pfn; pfn += cur_nr_pages) {
 		cond_resched();
-		pfns = min(nr_pages, PAGES_PER_SECTION
-				- (pfn & ~PAGE_SECTION_MASK));
-		__remove_section(pfn, pfns, map_offset, altmap);
-		pfn += pfns;
-		nr_pages -= pfns;
+		/* Select all remaining pages up to the next section boundary */
+		cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK));
+		__remove_section(pfn, cur_nr_pages, map_offset, altmap);
 		map_offset = 0;
 	}
 }
@@ -783,27 +758,18 @@ struct zone * zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
 	return default_zone_for_pfn(nid, start_pfn, nr_pages);
 }
 
-int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
+int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
+		       int online_type, int nid)
 {
 	unsigned long flags;
 	unsigned long onlined_pages = 0;
 	struct zone *zone;
 	int need_zonelists_rebuild = 0;
-	int nid;
 	int ret;
 	struct memory_notify arg;
-	struct memory_block *mem;
 
 	mem_hotplug_begin();
 
-	/*
-	 * We can't use pfn_to_nid() because nid might be stored in struct page
-	 * which is not yet initialized. Instead, we find nid from memory block.
-	 */
-	mem = find_memory_block(__pfn_to_section(pfn));
-	nid = mem->nid;
-	put_device(&mem->dev);
-
 	/* associate pfn range with the zone */
 	zone = zone_for_pfn_range(online_type, nid, pfn, nr_pages);
 	move_pfn_range_to_zone(zone, pfn, nr_pages, NULL);
@@ -1182,7 +1148,7 @@ static bool is_pageblock_removable_nolock(unsigned long pfn)
 	if (!zone_spans_pfn(zone, pfn))
 		return false;
 
-	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE,
+	return !has_unmovable_pages(zone, page, MIGRATE_MOVABLE,
 				    MEMORY_OFFLINE);
 }
 
@@ -1206,14 +1172,13 @@ bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
 }
 
 /*
- * Confirm all pages in a range [start, end) belong to the same zone.
- * When true, return its valid [start, end).
+ * Confirm all pages in a range [start, end) belong to the same zone (skipping
+ * memory holes). When true, return the zone.
  */
-int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
-			 unsigned long *valid_start, unsigned long *valid_end)
+struct zone *test_pages_in_a_zone(unsigned long start_pfn,
+				  unsigned long end_pfn)
 {
 	unsigned long pfn, sec_end_pfn;
-	unsigned long start, end;
 	struct zone *zone = NULL;
 	struct page *page;
 	int i;
@@ -1234,24 +1199,15 @@ int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
 				continue;
 			/* Check if we got outside of the zone */
 			if (zone && !zone_spans_pfn(zone, pfn + i))
-				return 0;
+				return NULL;
 			page = pfn_to_page(pfn + i);
 			if (zone && page_zone(page) != zone)
-				return 0;
-			if (!zone)
-				start = pfn + i;
+				return NULL;
 			zone = page_zone(page);
-			end = pfn + MAX_ORDER_NR_PAGES;
 		}
 	}
 
-	if (zone) {
-		*valid_start = start;
-		*valid_end = min(end, end_pfn);
-		return 1;
-	} else {
-		return 0;
-	}
+	return zone;
 }
 
 /*
@@ -1496,7 +1452,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
 	unsigned long offlined_pages = 0;
 	int ret, node, nr_isolate_pageblock;
 	unsigned long flags;
-	unsigned long valid_start, valid_end;
 	struct zone *zone;
 	struct memory_notify arg;
 	char *reason;
@@ -1521,14 +1476,12 @@ static int __ref __offline_pages(unsigned long start_pfn,
 
 	/* This makes hotplug much easier...and readable.
 	   we assume this for now. .*/
-	if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start,
-				  &valid_end)) {
+	zone = test_pages_in_a_zone(start_pfn, end_pfn);
+	if (!zone) {
 		ret = -EINVAL;
 		reason = "multizone range";
 		goto failed_removal;
 	}
-
-	zone = page_zone(pfn_to_page(valid_start));
 	node = zone_to_nid(zone);
 
 	/* set above range as isolated */
@@ -1764,8 +1717,6 @@ static int __ref try_remove_memory(int nid, u64 start, u64 size)
 
 	BUG_ON(check_hotplug_memory_range(start, size));
 
-	mem_hotplug_begin();
-
 	/*
 	 * All memory blocks must be offlined before removing memory.  Check
 	 * whether all memory blocks in question are offline and return error
@@ -1778,9 +1729,14 @@ static int __ref try_remove_memory(int nid, u64 start, u64 size)
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size, "System RAM");
 
-	/* remove memory block devices before removing memory */
+	/*
+	 * Memory block device removal under the device_hotplug_lock is
+	 * a barrier against racing online attempts.
+	 */
 	remove_memory_block_devices(start, size);
 
+	mem_hotplug_begin();
+
 	arch_remove_memory(nid, start, size, NULL);
 	memblock_free(start, size);
 	memblock_remove(start, size);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index b2920ae87a61..977c641f78cf 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2821,6 +2821,9 @@ int mpol_parse_str(char *str, struct mempolicy **mpol)
 	char *flags = strchr(str, '=');
 	int err = 1, mode;
 
+	if (flags)
+		*flags++ = '\0';	/* terminate mode string */
+
 	if (nodelist) {
 		/* NUL-terminate mode or flags string */
 		*nodelist++ = '\0';
@@ -2831,9 +2834,6 @@ int mpol_parse_str(char *str, struct mempolicy **mpol)
 	} else
 		nodes_clear(nodes);
 
-	if (flags)
-		*flags++ = '\0';	/* terminate mode string */
-
 	mode = match_string(policy_modes, MPOL_MAX, str);
 	if (mode < 0)
 		goto out;
diff --git a/mm/memremap.c b/mm/memremap.c
index c51c6bd2fe34..09b5b7adc773 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -27,7 +27,8 @@ static void devmap_managed_enable_put(void)
 
 static int devmap_managed_enable_get(struct dev_pagemap *pgmap)
 {
-	if (!pgmap->ops || !pgmap->ops->page_free) {
+	if (pgmap->type == MEMORY_DEVICE_PRIVATE &&
+	    (!pgmap->ops || !pgmap->ops->page_free)) {
 		WARN(1, "Missing page_free method\n");
 		return -EINVAL;
 	}
@@ -119,6 +120,8 @@ void memunmap_pages(struct dev_pagemap *pgmap)
 	nid = page_to_nid(first_page);
 
 	mem_hotplug_begin();
+	remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(res->start),
+				   PHYS_PFN(resource_size(res)));
 	if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
 		__remove_pages(PHYS_PFN(res->start),
 			       PHYS_PFN(resource_size(res)), NULL);
@@ -410,48 +413,42 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
 EXPORT_SYMBOL_GPL(get_dev_pagemap);
 
 #ifdef CONFIG_DEV_PAGEMAP_OPS
-void __put_devmap_managed_page(struct page *page)
+void free_devmap_managed_page(struct page *page)
 {
-	int count = page_ref_dec_return(page);
-
-	/*
-	 * If refcount is 1 then page is freed and refcount is stable as nobody
-	 * holds a reference on the page.
-	 */
-	if (count == 1) {
-		/* Clear Active bit in case of parallel mark_page_accessed */
-		__ClearPageActive(page);
-		__ClearPageWaiters(page);
+	/* notify page idle for dax */
+	if (!is_device_private_page(page)) {
+		wake_up_var(&page->_refcount);
+		return;
+	}
 
-		mem_cgroup_uncharge(page);
+	/* Clear Active bit in case of parallel mark_page_accessed */
+	__ClearPageActive(page);
+	__ClearPageWaiters(page);
 
-		/*
-		 * When a device_private page is freed, the page->mapping field
-		 * may still contain a (stale) mapping value. For example, the
-		 * lower bits of page->mapping may still identify the page as
-		 * an anonymous page. Ultimately, this entire field is just
-		 * stale and wrong, and it will cause errors if not cleared.
-		 * One example is:
-		 *
-		 *  migrate_vma_pages()
-		 *    migrate_vma_insert_page()
-		 *      page_add_new_anon_rmap()
-		 *        __page_set_anon_rmap()
-		 *          ...checks page->mapping, via PageAnon(page) call,
-		 *            and incorrectly concludes that the page is an
-		 *            anonymous page. Therefore, it incorrectly,
-		 *            silently fails to set up the new anon rmap.
-		 *
-		 * For other types of ZONE_DEVICE pages, migration is either
-		 * handled differently or not done at all, so there is no need
-		 * to clear page->mapping.
-		 */
-		if (is_device_private_page(page))
-			page->mapping = NULL;
+	mem_cgroup_uncharge(page);
 
-		page->pgmap->ops->page_free(page);
-	} else if (!count)
-		__put_page(page);
+	/*
+	 * When a device_private page is freed, the page->mapping field
+	 * may still contain a (stale) mapping value. For example, the
+	 * lower bits of page->mapping may still identify the page as an
+	 * anonymous page. Ultimately, this entire field is just stale
+	 * and wrong, and it will cause errors if not cleared.  One
+	 * example is:
+	 *
+	 *  migrate_vma_pages()
+	 *    migrate_vma_insert_page()
+	 *      page_add_new_anon_rmap()
+	 *        __page_set_anon_rmap()
+	 *          ...checks page->mapping, via PageAnon(page) call,
+	 *            and incorrectly concludes that the page is an
+	 *            anonymous page. Therefore, it incorrectly,
+	 *            silently fails to set up the new anon rmap.
+	 *
+	 * For other types of ZONE_DEVICE pages, migration is either
+	 * handled differently or not done at all, so there is no need
+	 * to clear page->mapping.
+	 */
+	page->mapping = NULL;
+	page->pgmap->ops->page_free(page);
 }
-EXPORT_SYMBOL(__put_devmap_managed_page);
 #endif /* CONFIG_DEV_PAGEMAP_OPS */
diff --git a/mm/migrate.c b/mm/migrate.c
index 86873b6f38a7..b1092876e537 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -48,6 +48,7 @@
 #include <linux/page_owner.h>
 #include <linux/sched/mm.h>
 #include <linux/ptrace.h>
+#include <linux/oom.h>
 
 #include <asm/tlbflush.h>
 
@@ -986,7 +987,7 @@ static int move_to_new_page(struct page *newpage, struct page *page,
 		}
 
 		/*
-		 * Anonymous and movable page->mapping will be cleard by
+		 * Anonymous and movable page->mapping will be cleared by
 		 * free_pages_prepare so don't reset it here for keeping
 		 * the type to work PageAnon, for example.
 		 */
@@ -1199,8 +1200,7 @@ out:
 		/*
 		 * A page that has been migrated has all references
 		 * removed and will be freed. A page that has not been
-		 * migrated will have kepts its references and be
-		 * restored.
+		 * migrated will have kept its references and be restored.
 		 */
 		list_del(&page->lru);
 
@@ -1627,8 +1627,19 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes,
 			start = i;
 		} else if (node != current_node) {
 			err = do_move_pages_to_node(mm, &pagelist, current_node);
-			if (err)
+			if (err) {
+				/*
+				 * Positive err means the number of failed
+				 * pages to migrate.  Since we are going to
+				 * abort and return the number of non-migrated
+				 * pages, so need to incude the rest of the
+				 * nr_pages that have not been attempted as
+				 * well.
+				 */
+				if (err > 0)
+					err += nr_pages - i - 1;
 				goto out;
+			}
 			err = store_status(status, start, current_node, i - start);
 			if (err)
 				goto out;
@@ -1659,8 +1670,11 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes,
 			goto out_flush;
 
 		err = do_move_pages_to_node(mm, &pagelist, current_node);
-		if (err)
+		if (err) {
+			if (err > 0)
+				err += nr_pages - i - 1;
 			goto out;
+		}
 		if (i > start) {
 			err = store_status(status, start, current_node, i - start);
 			if (err)
@@ -1674,9 +1688,16 @@ out_flush:
 
 	/* Make sure we do not overwrite the existing error */
 	err1 = do_move_pages_to_node(mm, &pagelist, current_node);
+	/*
+	 * Don't have to report non-attempted pages here since:
+	 *     - If the above loop is done gracefully all pages have been
+	 *       attempted.
+	 *     - If the above loop is aborted it means a fatal error
+	 *       happened, should return ret.
+	 */
 	if (!err1)
 		err1 = store_status(status, start, current_node, i - start);
-	if (!err)
+	if (err >= 0)
 		err = err1;
 out:
 	return err;
@@ -2130,12 +2151,13 @@ out_unlock:
 #ifdef CONFIG_DEVICE_PRIVATE
 static int migrate_vma_collect_hole(unsigned long start,
 				    unsigned long end,
+				    __always_unused int depth,
 				    struct mm_walk *walk)
 {
 	struct migrate_vma *migrate = walk->private;
 	unsigned long addr;
 
-	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
+	for (addr = start; addr < end; addr += PAGE_SIZE) {
 		migrate->src[migrate->npages] = MIGRATE_PFN_MIGRATE;
 		migrate->dst[migrate->npages] = 0;
 		migrate->npages++;
@@ -2152,7 +2174,7 @@ static int migrate_vma_collect_skip(unsigned long start,
 	struct migrate_vma *migrate = walk->private;
 	unsigned long addr;
 
-	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
+	for (addr = start; addr < end; addr += PAGE_SIZE) {
 		migrate->dst[migrate->npages] = 0;
 		migrate->src[migrate->npages++] = 0;
 	}
@@ -2174,7 +2196,7 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp,
 
 again:
 	if (pmd_none(*pmdp))
-		return migrate_vma_collect_hole(start, end, walk);
+		return migrate_vma_collect_hole(start, end, -1, walk);
 
 	if (pmd_trans_huge(*pmdp)) {
 		struct page *page;
@@ -2207,7 +2229,7 @@ again:
 				return migrate_vma_collect_skip(start, end,
 								walk);
 			if (pmd_none(*pmdp))
-				return migrate_vma_collect_hole(start, end,
+				return migrate_vma_collect_hole(start, end, -1,
 								walk);
 		}
 	}
@@ -2675,6 +2697,14 @@ int migrate_vma_setup(struct migrate_vma *args)
 }
 EXPORT_SYMBOL(migrate_vma_setup);
 
+/*
+ * This code closely matches the code in:
+ *   __handle_mm_fault()
+ *     handle_pte_fault()
+ *       do_anonymous_page()
+ * to map in an anonymous zero page but the struct page will be a ZONE_DEVICE
+ * private page.
+ */
 static void migrate_vma_insert_page(struct migrate_vma *migrate,
 				    unsigned long addr,
 				    struct page *page,
@@ -2755,30 +2785,24 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate,
 
 	ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl);
 
+	if (check_stable_address_space(mm))
+		goto unlock_abort;
+
 	if (pte_present(*ptep)) {
 		unsigned long pfn = pte_pfn(*ptep);
 
-		if (!is_zero_pfn(pfn)) {
-			pte_unmap_unlock(ptep, ptl);
-			mem_cgroup_cancel_charge(page, memcg, false);
-			goto abort;
-		}
+		if (!is_zero_pfn(pfn))
+			goto unlock_abort;
 		flush = true;
-	} else if (!pte_none(*ptep)) {
-		pte_unmap_unlock(ptep, ptl);
-		mem_cgroup_cancel_charge(page, memcg, false);
-		goto abort;
-	}
+	} else if (!pte_none(*ptep))
+		goto unlock_abort;
 
 	/*
-	 * Check for usefaultfd but do not deliver the fault. Instead,
+	 * Check for userfaultfd but do not deliver the fault. Instead,
 	 * just back off.
 	 */
-	if (userfaultfd_missing(vma)) {
-		pte_unmap_unlock(ptep, ptl);
-		mem_cgroup_cancel_charge(page, memcg, false);
-		goto abort;
-	}
+	if (userfaultfd_missing(vma))
+		goto unlock_abort;
 
 	inc_mm_counter(mm, MM_ANONPAGES);
 	page_add_new_anon_rmap(page, vma, addr, false);
@@ -2802,6 +2826,9 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate,
 	*src = MIGRATE_PFN_MIGRATE;
 	return;
 
+unlock_abort:
+	pte_unmap_unlock(ptep, ptl);
+	mem_cgroup_cancel_charge(page, memcg, false);
 abort:
 	*src &= ~MIGRATE_PFN_MIGRATE;
 }
@@ -2834,9 +2861,8 @@ void migrate_vma_pages(struct migrate_vma *migrate)
 		}
 
 		if (!page) {
-			if (!(migrate->src[i] & MIGRATE_PFN_MIGRATE)) {
+			if (!(migrate->src[i] & MIGRATE_PFN_MIGRATE))
 				continue;
-			}
 			if (!notified) {
 				notified = true;
 
diff --git a/mm/mincore.c b/mm/mincore.c
index 49b6fa2f6aa1..0e6dd9948f1a 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -112,6 +112,7 @@ static int __mincore_unmapped_range(unsigned long addr, unsigned long end,
 }
 
 static int mincore_unmapped_range(unsigned long addr, unsigned long end,
+				   __always_unused int depth,
 				   struct mm_walk *walk)
 {
 	walk->private += __mincore_unmapped_range(addr, end,
diff --git a/mm/mmap.c b/mm/mmap.c
index 71e4ffc83bcd..d681a20eb4ea 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -195,8 +195,6 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 	bool downgraded = false;
 	LIST_HEAD(uf);
 
-	brk = untagged_addr(brk);
-
 	if (down_write_killable(&mm->mmap_sem))
 		return -EINTR;
 
@@ -1270,26 +1268,22 @@ static struct anon_vma *reusable_anon_vma(struct vm_area_struct *old, struct vm_
  */
 struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *vma)
 {
-	struct anon_vma *anon_vma;
-	struct vm_area_struct *near;
-
-	near = vma->vm_next;
-	if (!near)
-		goto try_prev;
-
-	anon_vma = reusable_anon_vma(near, vma, near);
-	if (anon_vma)
-		return anon_vma;
-try_prev:
-	near = vma->vm_prev;
-	if (!near)
-		goto none;
-
-	anon_vma = reusable_anon_vma(near, near, vma);
-	if (anon_vma)
-		return anon_vma;
-none:
+	struct anon_vma *anon_vma = NULL;
+
+	/* Try next first. */
+	if (vma->vm_next) {
+		anon_vma = reusable_anon_vma(vma->vm_next, vma, vma->vm_next);
+		if (anon_vma)
+			return anon_vma;
+	}
+
+	/* Try prev next. */
+	if (vma->vm_prev)
+		anon_vma = reusable_anon_vma(vma->vm_prev, vma->vm_prev, vma);
+
 	/*
+	 * We might reach here with anon_vma == NULL if we can't find
+	 * any reusable anon_vma.
 	 * There's no absolute need to look only at touching neighbours:
 	 * we could search further afield for "compatible" anon_vmas.
 	 * But it would probably just be a waste of time searching,
@@ -1297,7 +1291,7 @@ none:
 	 * We're trying to allow mprotect remerging later on,
 	 * not trying to minimize memory used for anon_vmas.
 	 */
-	return NULL;
+	return anon_vma;
 }
 
 /*
@@ -1561,8 +1555,6 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
 	struct file *file = NULL;
 	unsigned long retval;
 
-	addr = untagged_addr(addr);
-
 	if (!(flags & MAP_ANONYMOUS)) {
 		audit_mmap_fd(fd, flags);
 		file = fget(fd);
@@ -3336,6 +3328,8 @@ static const struct vm_operations_struct special_mapping_vmops = {
 	.fault = special_mapping_fault,
 	.mremap = special_mapping_mremap,
 	.name = special_mapping_name,
+	/* vDSO code relies that VVAR can't be accessed remotely */
+	.access = NULL,
 };
 
 static const struct vm_operations_struct legacy_special_mapping_vmops = {
diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
index 7d70e5c78f97..a3538cb2bcbe 100644
--- a/mm/mmu_gather.c
+++ b/mm/mmu_gather.c
@@ -11,7 +11,7 @@
 #include <asm/pgalloc.h>
 #include <asm/tlb.h>
 
-#ifndef CONFIG_HAVE_MMU_GATHER_NO_GATHER
+#ifndef CONFIG_MMU_GATHER_NO_GATHER
 
 static bool tlb_next_batch(struct mmu_gather *tlb)
 {
@@ -69,7 +69,7 @@ bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page, int page_
 
 	VM_BUG_ON(!tlb->end);
 
-#ifdef CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
+#ifdef CONFIG_MMU_GATHER_PAGE_SIZE
 	VM_WARN_ON(tlb->page_size != page_size);
 #endif
 
@@ -89,58 +89,108 @@ bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page, int page_
 	return false;
 }
 
-#endif /* HAVE_MMU_GATHER_NO_GATHER */
+#endif /* MMU_GATHER_NO_GATHER */
 
-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+#ifdef CONFIG_MMU_GATHER_TABLE_FREE
 
-/*
- * See the comment near struct mmu_table_batch.
- */
+static void __tlb_remove_table_free(struct mmu_table_batch *batch)
+{
+	int i;
+
+	for (i = 0; i < batch->nr; i++)
+		__tlb_remove_table(batch->tables[i]);
+
+	free_page((unsigned long)batch);
+}
+
+#ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE
 
 /*
- * If we want tlb_remove_table() to imply TLB invalidates.
+ * Semi RCU freeing of the page directories.
+ *
+ * This is needed by some architectures to implement software pagetable walkers.
+ *
+ * gup_fast() and other software pagetable walkers do a lockless page-table
+ * walk and therefore needs some synchronization with the freeing of the page
+ * directories. The chosen means to accomplish that is by disabling IRQs over
+ * the walk.
+ *
+ * Architectures that use IPIs to flush TLBs will then automagically DTRT,
+ * since we unlink the page, flush TLBs, free the page. Since the disabling of
+ * IRQs delays the completion of the TLB flush we can never observe an already
+ * freed page.
+ *
+ * Architectures that do not have this (PPC) need to delay the freeing by some
+ * other means, this is that means.
+ *
+ * What we do is batch the freed directory pages (tables) and RCU free them.
+ * We use the sched RCU variant, as that guarantees that IRQ/preempt disabling
+ * holds off grace periods.
+ *
+ * However, in order to batch these pages we need to allocate storage, this
+ * allocation is deep inside the MM code and can thus easily fail on memory
+ * pressure. To guarantee progress we fall back to single table freeing, see
+ * the implementation of tlb_remove_table_one().
+ *
  */
-static inline void tlb_table_invalidate(struct mmu_gather *tlb)
-{
-#ifndef CONFIG_HAVE_RCU_TABLE_NO_INVALIDATE
-	/*
-	 * Invalidate page-table caches used by hardware walkers. Then we still
-	 * need to RCU-sched wait while freeing the pages because software
-	 * walkers can still be in-flight.
-	 */
-	tlb_flush_mmu_tlbonly(tlb);
-#endif
-}
 
 static void tlb_remove_table_smp_sync(void *arg)
 {
 	/* Simply deliver the interrupt */
 }
 
-static void tlb_remove_table_one(void *table)
+static void tlb_remove_table_sync_one(void)
 {
 	/*
 	 * This isn't an RCU grace period and hence the page-tables cannot be
 	 * assumed to be actually RCU-freed.
 	 *
 	 * It is however sufficient for software page-table walkers that rely on
-	 * IRQ disabling. See the comment near struct mmu_table_batch.
+	 * IRQ disabling.
 	 */
 	smp_call_function(tlb_remove_table_smp_sync, NULL, 1);
-	__tlb_remove_table(table);
 }
 
 static void tlb_remove_table_rcu(struct rcu_head *head)
 {
-	struct mmu_table_batch *batch;
-	int i;
+	__tlb_remove_table_free(container_of(head, struct mmu_table_batch, rcu));
+}
+
+static void tlb_remove_table_free(struct mmu_table_batch *batch)
+{
+	call_rcu(&batch->rcu, tlb_remove_table_rcu);
+}
 
-	batch = container_of(head, struct mmu_table_batch, rcu);
+#else /* !CONFIG_MMU_GATHER_RCU_TABLE_FREE */
 
-	for (i = 0; i < batch->nr; i++)
-		__tlb_remove_table(batch->tables[i]);
+static void tlb_remove_table_sync_one(void) { }
 
-	free_page((unsigned long)batch);
+static void tlb_remove_table_free(struct mmu_table_batch *batch)
+{
+	__tlb_remove_table_free(batch);
+}
+
+#endif /* CONFIG_MMU_GATHER_RCU_TABLE_FREE */
+
+/*
+ * If we want tlb_remove_table() to imply TLB invalidates.
+ */
+static inline void tlb_table_invalidate(struct mmu_gather *tlb)
+{
+	if (tlb_needs_table_invalidate()) {
+		/*
+		 * Invalidate page-table caches used by hardware walkers. Then
+		 * we still need to RCU-sched wait while freeing the pages
+		 * because software walkers can still be in-flight.
+		 */
+		tlb_flush_mmu_tlbonly(tlb);
+	}
+}
+
+static void tlb_remove_table_one(void *table)
+{
+	tlb_remove_table_sync_one();
+	__tlb_remove_table(table);
 }
 
 static void tlb_table_flush(struct mmu_gather *tlb)
@@ -149,7 +199,7 @@ static void tlb_table_flush(struct mmu_gather *tlb)
 
 	if (*batch) {
 		tlb_table_invalidate(tlb);
-		call_rcu(&(*batch)->rcu, tlb_remove_table_rcu);
+		tlb_remove_table_free(*batch);
 		*batch = NULL;
 	}
 }
@@ -173,14 +223,22 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
 		tlb_table_flush(tlb);
 }
 
-#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
+static inline void tlb_table_init(struct mmu_gather *tlb)
+{
+	tlb->batch = NULL;
+}
+
+#else /* !CONFIG_MMU_GATHER_TABLE_FREE */
+
+static inline void tlb_table_flush(struct mmu_gather *tlb) { }
+static inline void tlb_table_init(struct mmu_gather *tlb) { }
+
+#endif /* CONFIG_MMU_GATHER_TABLE_FREE */
 
 static void tlb_flush_mmu_free(struct mmu_gather *tlb)
 {
-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
 	tlb_table_flush(tlb);
-#endif
-#ifndef CONFIG_HAVE_MMU_GATHER_NO_GATHER
+#ifndef CONFIG_MMU_GATHER_NO_GATHER
 	tlb_batch_pages_flush(tlb);
 #endif
 }
@@ -211,7 +269,7 @@ void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
 	/* Is it from 0 to ~0? */
 	tlb->fullmm     = !(start | (end+1));
 
-#ifndef CONFIG_HAVE_MMU_GATHER_NO_GATHER
+#ifndef CONFIG_MMU_GATHER_NO_GATHER
 	tlb->need_flush_all = 0;
 	tlb->local.next = NULL;
 	tlb->local.nr   = 0;
@@ -220,10 +278,8 @@ void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
 	tlb->batch_count = 0;
 #endif
 
-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
-	tlb->batch = NULL;
-#endif
-#ifdef CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
+	tlb_table_init(tlb);
+#ifdef CONFIG_MMU_GATHER_PAGE_SIZE
 	tlb->page_size = 0;
 #endif
 
@@ -271,7 +327,7 @@ void tlb_finish_mmu(struct mmu_gather *tlb,
 
 	tlb_flush_mmu(tlb);
 
-#ifndef CONFIG_HAVE_MMU_GATHER_NO_GATHER
+#ifndef CONFIG_MMU_GATHER_NO_GATHER
 	tlb_batch_list_free(tlb);
 #endif
 	dec_tlb_flush_pending(tlb->mm);
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index f76ea05b1cb0..ef3973a5d34a 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -29,12 +29,12 @@ struct lockdep_map __mmu_notifier_invalidate_range_start_map = {
 #endif
 
 /*
- * The mmu notifier_mm structure is allocated and installed in
- * mm->mmu_notifier_mm inside the mm_take_all_locks() protected
+ * The mmu_notifier_subscriptions structure is allocated and installed in
+ * mm->notifier_subscriptions inside the mm_take_all_locks() protected
  * critical section and it's released only when mm_count reaches zero
  * in mmdrop().
  */
-struct mmu_notifier_mm {
+struct mmu_notifier_subscriptions {
 	/* all mmu notifiers registered in this mm are queued in this list */
 	struct hlist_head list;
 	bool has_itree;
@@ -65,80 +65,81 @@ struct mmu_notifier_mm {
  *
  * The write side has two states, fully excluded:
  *  - mm->active_invalidate_ranges != 0
- *  - mnn->invalidate_seq & 1 == True (odd)
+ *  - subscriptions->invalidate_seq & 1 == True (odd)
  *  - some range on the mm_struct is being invalidated
  *  - the itree is not allowed to change
  *
  * And partially excluded:
  *  - mm->active_invalidate_ranges != 0
- *  - mnn->invalidate_seq & 1 == False (even)
+ *  - subscriptions->invalidate_seq & 1 == False (even)
  *  - some range on the mm_struct is being invalidated
  *  - the itree is allowed to change
  *
- * Operations on mmu_notifier_mm->invalidate_seq (under spinlock):
+ * Operations on notifier_subscriptions->invalidate_seq (under spinlock):
  *    seq |= 1  # Begin writing
  *    seq++     # Release the writing state
  *    seq & 1   # True if a writer exists
  *
  * The later state avoids some expensive work on inv_end in the common case of
- * no mni monitoring the VA.
+ * no mmu_interval_notifier monitoring the VA.
  */
-static bool mn_itree_is_invalidating(struct mmu_notifier_mm *mmn_mm)
+static bool
+mn_itree_is_invalidating(struct mmu_notifier_subscriptions *subscriptions)
 {
-	lockdep_assert_held(&mmn_mm->lock);
-	return mmn_mm->invalidate_seq & 1;
+	lockdep_assert_held(&subscriptions->lock);
+	return subscriptions->invalidate_seq & 1;
 }
 
 static struct mmu_interval_notifier *
-mn_itree_inv_start_range(struct mmu_notifier_mm *mmn_mm,
+mn_itree_inv_start_range(struct mmu_notifier_subscriptions *subscriptions,
 			 const struct mmu_notifier_range *range,
 			 unsigned long *seq)
 {
 	struct interval_tree_node *node;
 	struct mmu_interval_notifier *res = NULL;
 
-	spin_lock(&mmn_mm->lock);
-	mmn_mm->active_invalidate_ranges++;
-	node = interval_tree_iter_first(&mmn_mm->itree, range->start,
+	spin_lock(&subscriptions->lock);
+	subscriptions->active_invalidate_ranges++;
+	node = interval_tree_iter_first(&subscriptions->itree, range->start,
 					range->end - 1);
 	if (node) {
-		mmn_mm->invalidate_seq |= 1;
+		subscriptions->invalidate_seq |= 1;
 		res = container_of(node, struct mmu_interval_notifier,
 				   interval_tree);
 	}
 
-	*seq = mmn_mm->invalidate_seq;
-	spin_unlock(&mmn_mm->lock);
+	*seq = subscriptions->invalidate_seq;
+	spin_unlock(&subscriptions->lock);
 	return res;
 }
 
 static struct mmu_interval_notifier *
-mn_itree_inv_next(struct mmu_interval_notifier *mni,
+mn_itree_inv_next(struct mmu_interval_notifier *interval_sub,
 		  const struct mmu_notifier_range *range)
 {
 	struct interval_tree_node *node;
 
-	node = interval_tree_iter_next(&mni->interval_tree, range->start,
-				       range->end - 1);
+	node = interval_tree_iter_next(&interval_sub->interval_tree,
+				       range->start, range->end - 1);
 	if (!node)
 		return NULL;
 	return container_of(node, struct mmu_interval_notifier, interval_tree);
 }
 
-static void mn_itree_inv_end(struct mmu_notifier_mm *mmn_mm)
+static void mn_itree_inv_end(struct mmu_notifier_subscriptions *subscriptions)
 {
-	struct mmu_interval_notifier *mni;
+	struct mmu_interval_notifier *interval_sub;
 	struct hlist_node *next;
 
-	spin_lock(&mmn_mm->lock);
-	if (--mmn_mm->active_invalidate_ranges ||
-	    !mn_itree_is_invalidating(mmn_mm)) {
-		spin_unlock(&mmn_mm->lock);
+	spin_lock(&subscriptions->lock);
+	if (--subscriptions->active_invalidate_ranges ||
+	    !mn_itree_is_invalidating(subscriptions)) {
+		spin_unlock(&subscriptions->lock);
 		return;
 	}
 
 	/* Make invalidate_seq even */
-	mmn_mm->invalidate_seq++;
+	subscriptions->invalidate_seq++;
 
 	/*
 	 * The inv_end incorporates a deferred mechanism like rtnl_unlock().
@@ -146,30 +147,31 @@ static void mn_itree_inv_end(struct mmu_notifier_mm *mmn_mm)
 	 * they are progressed. This arrangement for tree updates is used to
 	 * avoid using a blocking lock during invalidate_range_start.
 	 */
-	hlist_for_each_entry_safe(mni, next, &mmn_mm->deferred_list,
+	hlist_for_each_entry_safe(interval_sub, next,
+				  &subscriptions->deferred_list,
 				  deferred_item) {
-		if (RB_EMPTY_NODE(&mni->interval_tree.rb))
-			interval_tree_insert(&mni->interval_tree,
-					     &mmn_mm->itree);
+		if (RB_EMPTY_NODE(&interval_sub->interval_tree.rb))
+			interval_tree_insert(&interval_sub->interval_tree,
+					     &subscriptions->itree);
 		else
-			interval_tree_remove(&mni->interval_tree,
-					     &mmn_mm->itree);
-		hlist_del(&mni->deferred_item);
+			interval_tree_remove(&interval_sub->interval_tree,
+					     &subscriptions->itree);
+		hlist_del(&interval_sub->deferred_item);
 	}
-	spin_unlock(&mmn_mm->lock);
+	spin_unlock(&subscriptions->lock);
 
-	wake_up_all(&mmn_mm->wq);
+	wake_up_all(&subscriptions->wq);
 }
 
 /**
  * mmu_interval_read_begin - Begin a read side critical section against a VA
  *                           range
- * mni: The range to use
+ * interval_sub: The interval subscription
  *
  * mmu_iterval_read_begin()/mmu_iterval_read_retry() implement a
- * collision-retry scheme similar to seqcount for the VA range under mni. If
- * the mm invokes invalidation during the critical section then
- * mmu_interval_read_retry() will return true.
+ * collision-retry scheme similar to seqcount for the VA range under
+ * subscription. If the mm invokes invalidation during the critical section
+ * then mmu_interval_read_retry() will return true.
  *
  * This is useful to obtain shadow PTEs where teardown or setup of the SPTEs
  * require a blocking context.  The critical region formed by this can sleep,
@@ -180,68 +182,71 @@ static void mn_itree_inv_end(struct mmu_notifier_mm *mmn_mm)
  *
  * The return value should be passed to mmu_interval_read_retry().
  */
-unsigned long mmu_interval_read_begin(struct mmu_interval_notifier *mni)
+unsigned long
+mmu_interval_read_begin(struct mmu_interval_notifier *interval_sub)
 {
-	struct mmu_notifier_mm *mmn_mm = mni->mm->mmu_notifier_mm;
+	struct mmu_notifier_subscriptions *subscriptions =
+		interval_sub->mm->notifier_subscriptions;
 	unsigned long seq;
 	bool is_invalidating;
 
 	/*
-	 * If the mni has a different seq value under the user_lock than we
-	 * started with then it has collided.
+	 * If the subscription has a different seq value under the user_lock
+	 * than we started with then it has collided.
 	 *
-	 * If the mni currently has the same seq value as the mmn_mm seq, then
-	 * it is currently between invalidate_start/end and is colliding.
+	 * If the subscription currently has the same seq value as the
+	 * subscriptions seq, then it is currently between
+	 * invalidate_start/end and is colliding.
 	 *
 	 * The locking looks broadly like this:
 	 *   mn_tree_invalidate_start():          mmu_interval_read_begin():
 	 *                                         spin_lock
-	 *                                          seq = READ_ONCE(mni->invalidate_seq);
-	 *                                          seq == mmn_mm->invalidate_seq
+	 *                                          seq = READ_ONCE(interval_sub->invalidate_seq);
+	 *                                          seq == subs->invalidate_seq
 	 *                                         spin_unlock
 	 *    spin_lock
-	 *     seq = ++mmn_mm->invalidate_seq
+	 *     seq = ++subscriptions->invalidate_seq
 	 *    spin_unlock
 	 *     op->invalidate_range():
 	 *       user_lock
 	 *        mmu_interval_set_seq()
-	 *         mni->invalidate_seq = seq
+	 *         interval_sub->invalidate_seq = seq
 	 *       user_unlock
 	 *
 	 *                          [Required: mmu_interval_read_retry() == true]
 	 *
 	 *   mn_itree_inv_end():
 	 *    spin_lock
-	 *     seq = ++mmn_mm->invalidate_seq
+	 *     seq = ++subscriptions->invalidate_seq
 	 *    spin_unlock
 	 *
 	 *                                        user_lock
 	 *                                         mmu_interval_read_retry():
-	 *                                          mni->invalidate_seq != seq
+	 *                                          interval_sub->invalidate_seq != seq
 	 *                                        user_unlock
 	 *
 	 * Barriers are not needed here as any races here are closed by an
 	 * eventual mmu_interval_read_retry(), which provides a barrier via the
 	 * user_lock.
 	 */
-	spin_lock(&mmn_mm->lock);
+	spin_lock(&subscriptions->lock);
 	/* Pairs with the WRITE_ONCE in mmu_interval_set_seq() */
-	seq = READ_ONCE(mni->invalidate_seq);
-	is_invalidating = seq == mmn_mm->invalidate_seq;
-	spin_unlock(&mmn_mm->lock);
+	seq = READ_ONCE(interval_sub->invalidate_seq);
+	is_invalidating = seq == subscriptions->invalidate_seq;
+	spin_unlock(&subscriptions->lock);
 
 	/*
-	 * mni->invalidate_seq must always be set to an odd value via
+	 * interval_sub->invalidate_seq must always be set to an odd value via
 	 * mmu_interval_set_seq() using the provided cur_seq from
 	 * mn_itree_inv_start_range(). This ensures that if seq does wrap we
 	 * will always clear the below sleep in some reasonable time as
-	 * mmn_mm->invalidate_seq is even in the idle state.
+	 * subscriptions->invalidate_seq is even in the idle state.
 	 */
 	lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
 	lock_map_release(&__mmu_notifier_invalidate_range_start_map);
 	if (is_invalidating)
-		wait_event(mmn_mm->wq,
-			   READ_ONCE(mmn_mm->invalidate_seq) != seq);
+		wait_event(subscriptions->wq,
+			   READ_ONCE(subscriptions->invalidate_seq) != seq);
 
 	/*
 	 * Notice that mmu_interval_read_retry() can already be true at this
@@ -253,7 +258,7 @@ unsigned long mmu_interval_read_begin(struct mmu_interval_notifier *mni)
 }
 EXPORT_SYMBOL_GPL(mmu_interval_read_begin);
 
-static void mn_itree_release(struct mmu_notifier_mm *mmn_mm,
+static void mn_itree_release(struct mmu_notifier_subscriptions *subscriptions,
 			     struct mm_struct *mm)
 {
 	struct mmu_notifier_range range = {
@@ -263,17 +268,20 @@ static void mn_itree_release(struct mmu_notifier_mm *mmn_mm,
 		.start = 0,
 		.end = ULONG_MAX,
 	};
-	struct mmu_interval_notifier *mni;
+	struct mmu_interval_notifier *interval_sub;
 	unsigned long cur_seq;
 	bool ret;
 
-	for (mni = mn_itree_inv_start_range(mmn_mm, &range, &cur_seq); mni;
-	     mni = mn_itree_inv_next(mni, &range)) {
-		ret = mni->ops->invalidate(mni, &range, cur_seq);
+	for (interval_sub =
+		     mn_itree_inv_start_range(subscriptions, &range, &cur_seq);
+	     interval_sub;
+	     interval_sub = mn_itree_inv_next(interval_sub, &range)) {
+		ret = interval_sub->ops->invalidate(interval_sub, &range,
+						    cur_seq);
 		WARN_ON(!ret);
 	}
 
-	mn_itree_inv_end(mmn_mm);
+	mn_itree_inv_end(subscriptions);
 }
 
 /*
@@ -283,15 +291,15 @@ static void mn_itree_release(struct mmu_notifier_mm *mmn_mm,
  * in parallel despite there being no task using this mm any more,
  * through the vmas outside of the exit_mmap context, such as with
  * vmtruncate. This serializes against mmu_notifier_unregister with
- * the mmu_notifier_mm->lock in addition to SRCU and it serializes
- * against the other mmu notifiers with SRCU. struct mmu_notifier_mm
+ * the notifier_subscriptions->lock in addition to SRCU and it serializes
+ * against the other mmu notifiers with SRCU. struct mmu_notifier_subscriptions
  * can't go away from under us as exit_mmap holds an mm_count pin
  * itself.
  */
-static void mn_hlist_release(struct mmu_notifier_mm *mmn_mm,
+static void mn_hlist_release(struct mmu_notifier_subscriptions *subscriptions,
 			     struct mm_struct *mm)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int id;
 
 	/*
@@ -299,29 +307,29 @@ static void mn_hlist_release(struct mmu_notifier_mm *mmn_mm,
 	 * ->release returns.
 	 */
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mmn_mm->list, hlist)
+	hlist_for_each_entry_rcu(subscription, &subscriptions->list, hlist)
 		/*
 		 * If ->release runs before mmu_notifier_unregister it must be
 		 * handled, as it's the only way for the driver to flush all
 		 * existing sptes and stop the driver from establishing any more
 		 * sptes before all the pages in the mm are freed.
 		 */
-		if (mn->ops->release)
-			mn->ops->release(mn, mm);
+		if (subscription->ops->release)
+			subscription->ops->release(subscription, mm);
 
-	spin_lock(&mmn_mm->lock);
-	while (unlikely(!hlist_empty(&mmn_mm->list))) {
-		mn = hlist_entry(mmn_mm->list.first, struct mmu_notifier,
-				 hlist);
+	spin_lock(&subscriptions->lock);
+	while (unlikely(!hlist_empty(&subscriptions->list))) {
+		subscription = hlist_entry(subscriptions->list.first,
+					   struct mmu_notifier, hlist);
 		/*
 		 * We arrived before mmu_notifier_unregister so
 		 * mmu_notifier_unregister will do nothing other than to wait
 		 * for ->release to finish and for mmu_notifier_unregister to
 		 * return.
 		 */
-		hlist_del_init_rcu(&mn->hlist);
+		hlist_del_init_rcu(&subscription->hlist);
 	}
-	spin_unlock(&mmn_mm->lock);
+	spin_unlock(&subscriptions->lock);
 	srcu_read_unlock(&srcu, id);
 
 	/*
@@ -330,21 +338,22 @@ static void mn_hlist_release(struct mmu_notifier_mm *mmn_mm,
 	 * until the ->release method returns, if it was invoked by
 	 * mmu_notifier_unregister.
 	 *
-	 * The mmu_notifier_mm can't go away from under us because one mm_count
-	 * is held by exit_mmap.
+	 * The notifier_subscriptions can't go away from under us because
+	 * one mm_count is held by exit_mmap.
 	 */
 	synchronize_srcu(&srcu);
 }
 
 void __mmu_notifier_release(struct mm_struct *mm)
 {
-	struct mmu_notifier_mm *mmn_mm = mm->mmu_notifier_mm;
+	struct mmu_notifier_subscriptions *subscriptions =
+		mm->notifier_subscriptions;
 
-	if (mmn_mm->has_itree)
-		mn_itree_release(mmn_mm, mm);
+	if (subscriptions->has_itree)
+		mn_itree_release(subscriptions, mm);
 
-	if (!hlist_empty(&mmn_mm->list))
-		mn_hlist_release(mmn_mm, mm);
+	if (!hlist_empty(&subscriptions->list))
+		mn_hlist_release(subscriptions, mm);
 }
 
 /*
@@ -356,13 +365,15 @@ int __mmu_notifier_clear_flush_young(struct mm_struct *mm,
 					unsigned long start,
 					unsigned long end)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int young = 0, id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
-		if (mn->ops->clear_flush_young)
-			young |= mn->ops->clear_flush_young(mn, mm, start, end);
+	hlist_for_each_entry_rcu(subscription,
+				 &mm->notifier_subscriptions->list, hlist) {
+		if (subscription->ops->clear_flush_young)
+			young |= subscription->ops->clear_flush_young(
+				subscription, mm, start, end);
 	}
 	srcu_read_unlock(&srcu, id);
 
@@ -373,13 +384,15 @@ int __mmu_notifier_clear_young(struct mm_struct *mm,
 			       unsigned long start,
 			       unsigned long end)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int young = 0, id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
-		if (mn->ops->clear_young)
-			young |= mn->ops->clear_young(mn, mm, start, end);
+	hlist_for_each_entry_rcu(subscription,
+				 &mm->notifier_subscriptions->list, hlist) {
+		if (subscription->ops->clear_young)
+			young |= subscription->ops->clear_young(subscription,
+								mm, start, end);
 	}
 	srcu_read_unlock(&srcu, id);
 
@@ -389,13 +402,15 @@ int __mmu_notifier_clear_young(struct mm_struct *mm,
 int __mmu_notifier_test_young(struct mm_struct *mm,
 			      unsigned long address)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int young = 0, id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
-		if (mn->ops->test_young) {
-			young = mn->ops->test_young(mn, mm, address);
+	hlist_for_each_entry_rcu(subscription,
+				 &mm->notifier_subscriptions->list, hlist) {
+		if (subscription->ops->test_young) {
+			young = subscription->ops->test_young(subscription, mm,
+							      address);
 			if (young)
 				break;
 		}
@@ -408,28 +423,33 @@ int __mmu_notifier_test_young(struct mm_struct *mm,
 void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address,
 			       pte_t pte)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
-		if (mn->ops->change_pte)
-			mn->ops->change_pte(mn, mm, address, pte);
+	hlist_for_each_entry_rcu(subscription,
+				 &mm->notifier_subscriptions->list, hlist) {
+		if (subscription->ops->change_pte)
+			subscription->ops->change_pte(subscription, mm, address,
+						      pte);
 	}
 	srcu_read_unlock(&srcu, id);
 }
 
-static int mn_itree_invalidate(struct mmu_notifier_mm *mmn_mm,
+static int mn_itree_invalidate(struct mmu_notifier_subscriptions *subscriptions,
 			       const struct mmu_notifier_range *range)
 {
-	struct mmu_interval_notifier *mni;
+	struct mmu_interval_notifier *interval_sub;
 	unsigned long cur_seq;
 
-	for (mni = mn_itree_inv_start_range(mmn_mm, range, &cur_seq); mni;
-	     mni = mn_itree_inv_next(mni, range)) {
+	for (interval_sub =
+		     mn_itree_inv_start_range(subscriptions, range, &cur_seq);
+	     interval_sub;
+	     interval_sub = mn_itree_inv_next(interval_sub, range)) {
 		bool ret;
 
-		ret = mni->ops->invalidate(mni, range, cur_seq);
+		ret = interval_sub->ops->invalidate(interval_sub, range,
+						    cur_seq);
 		if (!ret) {
 			if (WARN_ON(mmu_notifier_range_blockable(range)))
 				continue;
@@ -443,31 +463,36 @@ out_would_block:
 	 * On -EAGAIN the non-blocking caller is not allowed to call
 	 * invalidate_range_end()
 	 */
-	mn_itree_inv_end(mmn_mm);
+	mn_itree_inv_end(subscriptions);
 	return -EAGAIN;
 }
 
-static int mn_hlist_invalidate_range_start(struct mmu_notifier_mm *mmn_mm,
-					   struct mmu_notifier_range *range)
+static int mn_hlist_invalidate_range_start(
+	struct mmu_notifier_subscriptions *subscriptions,
+	struct mmu_notifier_range *range)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int ret = 0;
 	int id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mmn_mm->list, hlist) {
-		if (mn->ops->invalidate_range_start) {
+	hlist_for_each_entry_rcu(subscription, &subscriptions->list, hlist) {
+		const struct mmu_notifier_ops *ops = subscription->ops;
+
+		if (ops->invalidate_range_start) {
 			int _ret;
 
 			if (!mmu_notifier_range_blockable(range))
 				non_block_start();
-			_ret = mn->ops->invalidate_range_start(mn, range);
+			_ret = ops->invalidate_range_start(subscription, range);
 			if (!mmu_notifier_range_blockable(range))
 				non_block_end();
 			if (_ret) {
 				pr_info("%pS callback failed with %d in %sblockable context.\n",
-					mn->ops->invalidate_range_start, _ret,
-					!mmu_notifier_range_blockable(range) ? "non-" : "");
+					ops->invalidate_range_start, _ret,
+					!mmu_notifier_range_blockable(range) ?
+						"non-" :
+						"");
 				WARN_ON(mmu_notifier_range_blockable(range) ||
 					_ret != -EAGAIN);
 				ret = _ret;
@@ -481,28 +506,29 @@ static int mn_hlist_invalidate_range_start(struct mmu_notifier_mm *mmn_mm,
 
 int __mmu_notifier_invalidate_range_start(struct mmu_notifier_range *range)
 {
-	struct mmu_notifier_mm *mmn_mm = range->mm->mmu_notifier_mm;
+	struct mmu_notifier_subscriptions *subscriptions =
+		range->mm->notifier_subscriptions;
 	int ret;
 
-	if (mmn_mm->has_itree) {
-		ret = mn_itree_invalidate(mmn_mm, range);
+	if (subscriptions->has_itree) {
+		ret = mn_itree_invalidate(subscriptions, range);
 		if (ret)
 			return ret;
 	}
-	if (!hlist_empty(&mmn_mm->list))
-		return mn_hlist_invalidate_range_start(mmn_mm, range);
+	if (!hlist_empty(&subscriptions->list))
+		return mn_hlist_invalidate_range_start(subscriptions, range);
 	return 0;
 }
 
-static void mn_hlist_invalidate_end(struct mmu_notifier_mm *mmn_mm,
-				    struct mmu_notifier_range *range,
-				    bool only_end)
+static void
+mn_hlist_invalidate_end(struct mmu_notifier_subscriptions *subscriptions,
+			struct mmu_notifier_range *range, bool only_end)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mmn_mm->list, hlist) {
+	hlist_for_each_entry_rcu(subscription, &subscriptions->list, hlist) {
 		/*
 		 * Call invalidate_range here too to avoid the need for the
 		 * subsystem of having to register an invalidate_range_end
@@ -516,14 +542,16 @@ static void mn_hlist_invalidate_end(struct mmu_notifier_mm *mmn_mm,
 		 * is safe to do when we know that a call to invalidate_range()
 		 * already happen under page table lock.
 		 */
-		if (!only_end && mn->ops->invalidate_range)
-			mn->ops->invalidate_range(mn, range->mm,
-						  range->start,
-						  range->end);
-		if (mn->ops->invalidate_range_end) {
+		if (!only_end && subscription->ops->invalidate_range)
+			subscription->ops->invalidate_range(subscription,
+							    range->mm,
+							    range->start,
+							    range->end);
+		if (subscription->ops->invalidate_range_end) {
 			if (!mmu_notifier_range_blockable(range))
 				non_block_start();
-			mn->ops->invalidate_range_end(mn, range);
+			subscription->ops->invalidate_range_end(subscription,
+								range);
 			if (!mmu_notifier_range_blockable(range))
 				non_block_end();
 		}
@@ -534,27 +562,30 @@ static void mn_hlist_invalidate_end(struct mmu_notifier_mm *mmn_mm,
 void __mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range,
 					 bool only_end)
 {
-	struct mmu_notifier_mm *mmn_mm = range->mm->mmu_notifier_mm;
+	struct mmu_notifier_subscriptions *subscriptions =
+		range->mm->notifier_subscriptions;
 
 	lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
-	if (mmn_mm->has_itree)
-		mn_itree_inv_end(mmn_mm);
+	if (subscriptions->has_itree)
+		mn_itree_inv_end(subscriptions);
 
-	if (!hlist_empty(&mmn_mm->list))
-		mn_hlist_invalidate_end(mmn_mm, range, only_end);
+	if (!hlist_empty(&subscriptions->list))
+		mn_hlist_invalidate_end(subscriptions, range, only_end);
 	lock_map_release(&__mmu_notifier_invalidate_range_start_map);
 }
 
 void __mmu_notifier_invalidate_range(struct mm_struct *mm,
 				  unsigned long start, unsigned long end)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int id;
 
 	id = srcu_read_lock(&srcu);
-	hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
-		if (mn->ops->invalidate_range)
-			mn->ops->invalidate_range(mn, mm, start, end);
+	hlist_for_each_entry_rcu(subscription,
+				 &mm->notifier_subscriptions->list, hlist) {
+		if (subscription->ops->invalidate_range)
+			subscription->ops->invalidate_range(subscription, mm,
+							    start, end);
 	}
 	srcu_read_unlock(&srcu, id);
 }
@@ -564,9 +595,10 @@ void __mmu_notifier_invalidate_range(struct mm_struct *mm,
  * write mode. A NULL mn signals the notifier is being registered for itree
  * mode.
  */
-int __mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm)
+int __mmu_notifier_register(struct mmu_notifier *subscription,
+			    struct mm_struct *mm)
 {
-	struct mmu_notifier_mm *mmu_notifier_mm = NULL;
+	struct mmu_notifier_subscriptions *subscriptions = NULL;
 	int ret;
 
 	lockdep_assert_held_write(&mm->mmap_sem);
@@ -579,23 +611,23 @@ int __mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm)
 		fs_reclaim_release(GFP_KERNEL);
 	}
 
-	if (!mm->mmu_notifier_mm) {
+	if (!mm->notifier_subscriptions) {
 		/*
 		 * kmalloc cannot be called under mm_take_all_locks(), but we
-		 * know that mm->mmu_notifier_mm can't change while we hold
-		 * the write side of the mmap_sem.
+		 * know that mm->notifier_subscriptions can't change while we
+		 * hold the write side of the mmap_sem.
 		 */
-		mmu_notifier_mm =
-			kzalloc(sizeof(struct mmu_notifier_mm), GFP_KERNEL);
-		if (!mmu_notifier_mm)
+		subscriptions = kzalloc(
+			sizeof(struct mmu_notifier_subscriptions), GFP_KERNEL);
+		if (!subscriptions)
 			return -ENOMEM;
 
-		INIT_HLIST_HEAD(&mmu_notifier_mm->list);
-		spin_lock_init(&mmu_notifier_mm->lock);
-		mmu_notifier_mm->invalidate_seq = 2;
-		mmu_notifier_mm->itree = RB_ROOT_CACHED;
-		init_waitqueue_head(&mmu_notifier_mm->wq);
-		INIT_HLIST_HEAD(&mmu_notifier_mm->deferred_list);
+		INIT_HLIST_HEAD(&subscriptions->list);
+		spin_lock_init(&subscriptions->lock);
+		subscriptions->invalidate_seq = 2;
+		subscriptions->itree = RB_ROOT_CACHED;
+		init_waitqueue_head(&subscriptions->wq);
+		INIT_HLIST_HEAD(&subscriptions->deferred_list);
 	}
 
 	ret = mm_take_all_locks(mm);
@@ -610,34 +642,36 @@ int __mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm)
 	 * We can't race against any other mmu notifier method either
 	 * thanks to mm_take_all_locks().
 	 *
-	 * release semantics on the initialization of the mmu_notifier_mm's
-	 * contents are provided for unlocked readers.  acquire can only be
-	 * used while holding the mmgrab or mmget, and is safe because once
-	 * created the mmu_notififer_mm is not freed until the mm is
-	 * destroyed.  As above, users holding the mmap_sem or one of the
+	 * release semantics on the initialization of the
+	 * mmu_notifier_subscriptions's contents are provided for unlocked
+	 * readers.  acquire can only be used while holding the mmgrab or
+	 * mmget, and is safe because once created the
+	 * mmu_notifier_subscriptions is not freed until the mm is destroyed.
+	 * As above, users holding the mmap_sem or one of the
 	 * mm_take_all_locks() do not need to use acquire semantics.
 	 */
-	if (mmu_notifier_mm)
-		smp_store_release(&mm->mmu_notifier_mm, mmu_notifier_mm);
+	if (subscriptions)
+		smp_store_release(&mm->notifier_subscriptions, subscriptions);
 
-	if (mn) {
+	if (subscription) {
 		/* Pairs with the mmdrop in mmu_notifier_unregister_* */
 		mmgrab(mm);
-		mn->mm = mm;
-		mn->users = 1;
+		subscription->mm = mm;
+		subscription->users = 1;
 
-		spin_lock(&mm->mmu_notifier_mm->lock);
-		hlist_add_head_rcu(&mn->hlist, &mm->mmu_notifier_mm->list);
-		spin_unlock(&mm->mmu_notifier_mm->lock);
+		spin_lock(&mm->notifier_subscriptions->lock);
+		hlist_add_head_rcu(&subscription->hlist,
+				   &mm->notifier_subscriptions->list);
+		spin_unlock(&mm->notifier_subscriptions->lock);
 	} else
-		mm->mmu_notifier_mm->has_itree = true;
+		mm->notifier_subscriptions->has_itree = true;
 
 	mm_drop_all_locks(mm);
 	BUG_ON(atomic_read(&mm->mm_users) <= 0);
 	return 0;
 
 out_clean:
-	kfree(mmu_notifier_mm);
+	kfree(subscriptions);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(__mmu_notifier_register);
@@ -658,15 +692,16 @@ EXPORT_SYMBOL_GPL(__mmu_notifier_register);
  * mmu_notifier_unregister() or mmu_notifier_put() must be always called to
  * unregister the notifier.
  *
- * While the caller has a mmu_notifier get the mn->mm pointer will remain
+ * While the caller has a mmu_notifier get the subscription->mm pointer will remain
  * valid, and can be converted to an active mm pointer via mmget_not_zero().
  */
-int mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm)
+int mmu_notifier_register(struct mmu_notifier *subscription,
+			  struct mm_struct *mm)
 {
 	int ret;
 
 	down_write(&mm->mmap_sem);
-	ret = __mmu_notifier_register(mn, mm);
+	ret = __mmu_notifier_register(subscription, mm);
 	up_write(&mm->mmap_sem);
 	return ret;
 }
@@ -675,21 +710,22 @@ EXPORT_SYMBOL_GPL(mmu_notifier_register);
 static struct mmu_notifier *
 find_get_mmu_notifier(struct mm_struct *mm, const struct mmu_notifier_ops *ops)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 
-	spin_lock(&mm->mmu_notifier_mm->lock);
-	hlist_for_each_entry_rcu (mn, &mm->mmu_notifier_mm->list, hlist) {
-		if (mn->ops != ops)
+	spin_lock(&mm->notifier_subscriptions->lock);
+	hlist_for_each_entry_rcu(subscription,
+				 &mm->notifier_subscriptions->list, hlist) {
+		if (subscription->ops != ops)
 			continue;
 
-		if (likely(mn->users != UINT_MAX))
-			mn->users++;
+		if (likely(subscription->users != UINT_MAX))
+			subscription->users++;
 		else
-			mn = ERR_PTR(-EOVERFLOW);
-		spin_unlock(&mm->mmu_notifier_mm->lock);
-		return mn;
+			subscription = ERR_PTR(-EOVERFLOW);
+		spin_unlock(&mm->notifier_subscriptions->lock);
+		return subscription;
 	}
-	spin_unlock(&mm->mmu_notifier_mm->lock);
+	spin_unlock(&mm->notifier_subscriptions->lock);
 	return NULL;
 }
 
@@ -713,37 +749,37 @@ find_get_mmu_notifier(struct mm_struct *mm, const struct mmu_notifier_ops *ops)
 struct mmu_notifier *mmu_notifier_get_locked(const struct mmu_notifier_ops *ops,
 					     struct mm_struct *mm)
 {
-	struct mmu_notifier *mn;
+	struct mmu_notifier *subscription;
 	int ret;
 
 	lockdep_assert_held_write(&mm->mmap_sem);
 
-	if (mm->mmu_notifier_mm) {
-		mn = find_get_mmu_notifier(mm, ops);
-		if (mn)
-			return mn;
+	if (mm->notifier_subscriptions) {
+		subscription = find_get_mmu_notifier(mm, ops);
+		if (subscription)
+			return subscription;
 	}
 
-	mn = ops->alloc_notifier(mm);
-	if (IS_ERR(mn))
-		return mn;
-	mn->ops = ops;
-	ret = __mmu_notifier_register(mn, mm);
+	subscription = ops->alloc_notifier(mm);
+	if (IS_ERR(subscription))
+		return subscription;
+	subscription->ops = ops;
+	ret = __mmu_notifier_register(subscription, mm);
 	if (ret)
 		goto out_free;
-	return mn;
+	return subscription;
 out_free:
-	mn->ops->free_notifier(mn);
+	subscription->ops->free_notifier(subscription);
 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(mmu_notifier_get_locked);
 
 /* this is called after the last mmu_notifier_unregister() returned */
-void __mmu_notifier_mm_destroy(struct mm_struct *mm)
+void __mmu_notifier_subscriptions_destroy(struct mm_struct *mm)
 {
-	BUG_ON(!hlist_empty(&mm->mmu_notifier_mm->list));
-	kfree(mm->mmu_notifier_mm);
-	mm->mmu_notifier_mm = LIST_POISON1; /* debug */
+	BUG_ON(!hlist_empty(&mm->notifier_subscriptions->list));
+	kfree(mm->notifier_subscriptions);
+	mm->notifier_subscriptions = LIST_POISON1; /* debug */
 }
 
 /*
@@ -756,11 +792,12 @@ void __mmu_notifier_mm_destroy(struct mm_struct *mm)
  * and only after mmu_notifier_unregister returned we're guaranteed
  * that ->release or any other method can't run anymore.
  */
-void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm)
+void mmu_notifier_unregister(struct mmu_notifier *subscription,
+			     struct mm_struct *mm)
 {
 	BUG_ON(atomic_read(&mm->mm_count) <= 0);
 
-	if (!hlist_unhashed(&mn->hlist)) {
+	if (!hlist_unhashed(&subscription->hlist)) {
 		/*
 		 * SRCU here will force exit_mmap to wait for ->release to
 		 * finish before freeing the pages.
@@ -772,17 +809,17 @@ void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm)
 		 * exit_mmap will block in mmu_notifier_release to guarantee
 		 * that ->release is called before freeing the pages.
 		 */
-		if (mn->ops->release)
-			mn->ops->release(mn, mm);
+		if (subscription->ops->release)
+			subscription->ops->release(subscription, mm);
 		srcu_read_unlock(&srcu, id);
 
-		spin_lock(&mm->mmu_notifier_mm->lock);
+		spin_lock(&mm->notifier_subscriptions->lock);
 		/*
 		 * Can not use list_del_rcu() since __mmu_notifier_release
 		 * can delete it before we hold the lock.
 		 */
-		hlist_del_init_rcu(&mn->hlist);
-		spin_unlock(&mm->mmu_notifier_mm->lock);
+		hlist_del_init_rcu(&subscription->hlist);
+		spin_unlock(&mm->notifier_subscriptions->lock);
 	}
 
 	/*
@@ -799,10 +836,11 @@ EXPORT_SYMBOL_GPL(mmu_notifier_unregister);
 
 static void mmu_notifier_free_rcu(struct rcu_head *rcu)
 {
-	struct mmu_notifier *mn = container_of(rcu, struct mmu_notifier, rcu);
-	struct mm_struct *mm = mn->mm;
+	struct mmu_notifier *subscription =
+		container_of(rcu, struct mmu_notifier, rcu);
+	struct mm_struct *mm = subscription->mm;
 
-	mn->ops->free_notifier(mn);
+	subscription->ops->free_notifier(subscription);
 	/* Pairs with the get in __mmu_notifier_register() */
 	mmdrop(mm);
 }
@@ -829,39 +867,40 @@ static void mmu_notifier_free_rcu(struct rcu_head *rcu)
  * Modules calling this function must call mmu_notifier_synchronize() in
  * their __exit functions to ensure the async work is completed.
  */
-void mmu_notifier_put(struct mmu_notifier *mn)
+void mmu_notifier_put(struct mmu_notifier *subscription)
 {
-	struct mm_struct *mm = mn->mm;
+	struct mm_struct *mm = subscription->mm;
 
-	spin_lock(&mm->mmu_notifier_mm->lock);
-	if (WARN_ON(!mn->users) || --mn->users)
+	spin_lock(&mm->notifier_subscriptions->lock);
+	if (WARN_ON(!subscription->users) || --subscription->users)
 		goto out_unlock;
-	hlist_del_init_rcu(&mn->hlist);
-	spin_unlock(&mm->mmu_notifier_mm->lock);
+	hlist_del_init_rcu(&subscription->hlist);
+	spin_unlock(&mm->notifier_subscriptions->lock);
 
-	call_srcu(&srcu, &mn->rcu, mmu_notifier_free_rcu);
+	call_srcu(&srcu, &subscription->rcu, mmu_notifier_free_rcu);
 	return;
 
 out_unlock:
-	spin_unlock(&mm->mmu_notifier_mm->lock);
+	spin_unlock(&mm->notifier_subscriptions->lock);
 }
 EXPORT_SYMBOL_GPL(mmu_notifier_put);
 
 static int __mmu_interval_notifier_insert(
-	struct mmu_interval_notifier *mni, struct mm_struct *mm,
-	struct mmu_notifier_mm *mmn_mm, unsigned long start,
+	struct mmu_interval_notifier *interval_sub, struct mm_struct *mm,
+	struct mmu_notifier_subscriptions *subscriptions, unsigned long start,
 	unsigned long length, const struct mmu_interval_notifier_ops *ops)
 {
-	mni->mm = mm;
-	mni->ops = ops;
-	RB_CLEAR_NODE(&mni->interval_tree.rb);
-	mni->interval_tree.start = start;
+	interval_sub->mm = mm;
+	interval_sub->ops = ops;
+	RB_CLEAR_NODE(&interval_sub->interval_tree.rb);
+	interval_sub->interval_tree.start = start;
 	/*
 	 * Note that the representation of the intervals in the interval tree
 	 * considers the ending point as contained in the interval.
 	 */
 	if (length == 0 ||
-	    check_add_overflow(start, length - 1, &mni->interval_tree.last))
+	    check_add_overflow(start, length - 1,
+			       &interval_sub->interval_tree.last))
 		return -EOVERFLOW;
 
 	/* Must call with a mmget() held */
@@ -881,38 +920,40 @@ static int __mmu_interval_notifier_insert(
 	 * possibility for live lock, instead defer the add to
 	 * mn_itree_inv_end() so this algorithm is deterministic.
 	 *
-	 * In all cases the value for the mni->invalidate_seq should be
+	 * In all cases the value for the interval_sub->invalidate_seq should be
 	 * odd, see mmu_interval_read_begin()
 	 */
-	spin_lock(&mmn_mm->lock);
-	if (mmn_mm->active_invalidate_ranges) {
-		if (mn_itree_is_invalidating(mmn_mm))
-			hlist_add_head(&mni->deferred_item,
-				       &mmn_mm->deferred_list);
+	spin_lock(&subscriptions->lock);
+	if (subscriptions->active_invalidate_ranges) {
+		if (mn_itree_is_invalidating(subscriptions))
+			hlist_add_head(&interval_sub->deferred_item,
+				       &subscriptions->deferred_list);
 		else {
-			mmn_mm->invalidate_seq |= 1;
-			interval_tree_insert(&mni->interval_tree,
-					     &mmn_mm->itree);
+			subscriptions->invalidate_seq |= 1;
+			interval_tree_insert(&interval_sub->interval_tree,
+					     &subscriptions->itree);
 		}
-		mni->invalidate_seq = mmn_mm->invalidate_seq;
+		interval_sub->invalidate_seq = subscriptions->invalidate_seq;
 	} else {
-		WARN_ON(mn_itree_is_invalidating(mmn_mm));
+		WARN_ON(mn_itree_is_invalidating(subscriptions));
 		/*
-		 * The starting seq for a mni not under invalidation should be
-		 * odd, not equal to the current invalidate_seq and
+		 * The starting seq for a subscription not under invalidation
+		 * should be odd, not equal to the current invalidate_seq and
 		 * invalidate_seq should not 'wrap' to the new seq any time
 		 * soon.
 		 */
-		mni->invalidate_seq = mmn_mm->invalidate_seq - 1;
-		interval_tree_insert(&mni->interval_tree, &mmn_mm->itree);
+		interval_sub->invalidate_seq =
+			subscriptions->invalidate_seq - 1;
+		interval_tree_insert(&interval_sub->interval_tree,
+				     &subscriptions->itree);
 	}
-	spin_unlock(&mmn_mm->lock);
+	spin_unlock(&subscriptions->lock);
 	return 0;
 }
 
 /**
  * mmu_interval_notifier_insert - Insert an interval notifier
- * @mni: Interval notifier to register
+ * @interval_sub: Interval subscription to register
  * @start: Starting virtual address to monitor
  * @length: Length of the range to monitor
  * @mm : mm_struct to attach to
@@ -925,53 +966,53 @@ static int __mmu_interval_notifier_insert(
  * The caller must use the normal interval notifier read flow via
  * mmu_interval_read_begin() to establish SPTEs for this range.
  */
-int mmu_interval_notifier_insert(struct mmu_interval_notifier *mni,
+int mmu_interval_notifier_insert(struct mmu_interval_notifier *interval_sub,
 				 struct mm_struct *mm, unsigned long start,
 				 unsigned long length,
 				 const struct mmu_interval_notifier_ops *ops)
 {
-	struct mmu_notifier_mm *mmn_mm;
+	struct mmu_notifier_subscriptions *subscriptions;
 	int ret;
 
 	might_lock(&mm->mmap_sem);
 
-	mmn_mm = smp_load_acquire(&mm->mmu_notifier_mm);
-	if (!mmn_mm || !mmn_mm->has_itree) {
+	subscriptions = smp_load_acquire(&mm->notifier_subscriptions);
+	if (!subscriptions || !subscriptions->has_itree) {
 		ret = mmu_notifier_register(NULL, mm);
 		if (ret)
 			return ret;
-		mmn_mm = mm->mmu_notifier_mm;
+		subscriptions = mm->notifier_subscriptions;
 	}
-	return __mmu_interval_notifier_insert(mni, mm, mmn_mm, start, length,
-					      ops);
+	return __mmu_interval_notifier_insert(interval_sub, mm, subscriptions,
+					      start, length, ops);
 }
 EXPORT_SYMBOL_GPL(mmu_interval_notifier_insert);
 
 int mmu_interval_notifier_insert_locked(
-	struct mmu_interval_notifier *mni, struct mm_struct *mm,
+	struct mmu_interval_notifier *interval_sub, struct mm_struct *mm,
 	unsigned long start, unsigned long length,
 	const struct mmu_interval_notifier_ops *ops)
 {
-	struct mmu_notifier_mm *mmn_mm;
+	struct mmu_notifier_subscriptions *subscriptions =
+		mm->notifier_subscriptions;
 	int ret;
 
 	lockdep_assert_held_write(&mm->mmap_sem);
 
-	mmn_mm = mm->mmu_notifier_mm;
-	if (!mmn_mm || !mmn_mm->has_itree) {
+	if (!subscriptions || !subscriptions->has_itree) {
 		ret = __mmu_notifier_register(NULL, mm);
 		if (ret)
 			return ret;
-		mmn_mm = mm->mmu_notifier_mm;
+		subscriptions = mm->notifier_subscriptions;
 	}
-	return __mmu_interval_notifier_insert(mni, mm, mmn_mm, start, length,
-					      ops);
+	return __mmu_interval_notifier_insert(interval_sub, mm, subscriptions,
+					      start, length, ops);
 }
 EXPORT_SYMBOL_GPL(mmu_interval_notifier_insert_locked);
 
 /**
  * mmu_interval_notifier_remove - Remove a interval notifier
- * @mni: Interval notifier to unregister
+ * @interval_sub: Interval subscription to unregister
  *
  * This function must be paired with mmu_interval_notifier_insert(). It cannot
  * be called from any ops callback.
@@ -979,32 +1020,34 @@ EXPORT_SYMBOL_GPL(mmu_interval_notifier_insert_locked);
  * Once this returns ops callbacks are no longer running on other CPUs and
  * will not be called in future.
  */
-void mmu_interval_notifier_remove(struct mmu_interval_notifier *mni)
+void mmu_interval_notifier_remove(struct mmu_interval_notifier *interval_sub)
 {
-	struct mm_struct *mm = mni->mm;
-	struct mmu_notifier_mm *mmn_mm = mm->mmu_notifier_mm;
+	struct mm_struct *mm = interval_sub->mm;
+	struct mmu_notifier_subscriptions *subscriptions =
+		mm->notifier_subscriptions;
 	unsigned long seq = 0;
 
 	might_sleep();
 
-	spin_lock(&mmn_mm->lock);
-	if (mn_itree_is_invalidating(mmn_mm)) {
+	spin_lock(&subscriptions->lock);
+	if (mn_itree_is_invalidating(subscriptions)) {
 		/*
 		 * remove is being called after insert put this on the
 		 * deferred list, but before the deferred list was processed.
 		 */
-		if (RB_EMPTY_NODE(&mni->interval_tree.rb)) {
-			hlist_del(&mni->deferred_item);
+		if (RB_EMPTY_NODE(&interval_sub->interval_tree.rb)) {
+			hlist_del(&interval_sub->deferred_item);
 		} else {
-			hlist_add_head(&mni->deferred_item,
-				       &mmn_mm->deferred_list);
-			seq = mmn_mm->invalidate_seq;
+			hlist_add_head(&interval_sub->deferred_item,
+				       &subscriptions->deferred_list);
+			seq = subscriptions->invalidate_seq;
 		}
 	} else {
-		WARN_ON(RB_EMPTY_NODE(&mni->interval_tree.rb));
-		interval_tree_remove(&mni->interval_tree, &mmn_mm->itree);
+		WARN_ON(RB_EMPTY_NODE(&interval_sub->interval_tree.rb));
+		interval_tree_remove(&interval_sub->interval_tree,
+				     &subscriptions->itree);
 	}
-	spin_unlock(&mmn_mm->lock);
+	spin_unlock(&subscriptions->lock);
 
 	/*
 	 * The possible sleep on progress in the invalidation requires the
@@ -1013,8 +1056,8 @@ void mmu_interval_notifier_remove(struct mmu_interval_notifier *mni)
 	lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
 	lock_map_release(&__mmu_notifier_invalidate_range_start_map);
 	if (seq)
-		wait_event(mmn_mm->wq,
-			   READ_ONCE(mmn_mm->invalidate_seq) != seq);
+		wait_event(subscriptions->wq,
+			   READ_ONCE(subscriptions->invalidate_seq) != seq);
 
 	/* pairs with mmgrab in mmu_interval_notifier_insert() */
 	mmdrop(mm);
diff --git a/mm/mremap.c b/mm/mremap.c
index 122938dcec15..af363063ea23 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -607,7 +607,6 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
 	LIST_HEAD(uf_unmap);
 
 	addr = untagged_addr(addr);
-	new_addr = untagged_addr(new_addr);
 
 	if (flags & ~(MREMAP_FIXED | MREMAP_MAYMOVE))
 		return ret;
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index d58c481b3df8..dfc357614e56 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -26,6 +26,7 @@
 #include <linux/sched/mm.h>
 #include <linux/sched/coredump.h>
 #include <linux/sched/task.h>
+#include <linux/sched/debug.h>
 #include <linux/swap.h>
 #include <linux/timex.h>
 #include <linux/jiffies.h>
@@ -620,6 +621,7 @@ static void oom_reap_task(struct task_struct *tsk)
 
 	pr_info("oom_reaper: unable to reap pid:%d (%s)\n",
 		task_pid_nr(tsk), tsk->comm);
+	sched_show_task(tsk);
 	debug_show_all_locks();
 
 done:
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d047bf7d8fd4..3c4eb750a199 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5848,6 +5848,23 @@ overlap_memmap_init(unsigned long zone, unsigned long *pfn)
 	return false;
 }
 
+#ifdef CONFIG_SPARSEMEM
+/* Skip PFNs that belong to non-present sections */
+static inline __meminit unsigned long next_pfn(unsigned long pfn)
+{
+	const unsigned long section_nr = pfn_to_section_nr(++pfn);
+
+	if (present_section_nr(section_nr))
+		return pfn;
+	return section_nr_to_pfn(next_present_section_nr(section_nr));
+}
+#else
+static inline __meminit unsigned long next_pfn(unsigned long pfn)
+{
+	return pfn++;
+}
+#endif
+
 /*
  * Initially all pages are reserved - free ones are freed
  * up by memblock_free_all() once the early boot process is
@@ -5881,16 +5898,20 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 	}
 #endif
 
-	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
+	for (pfn = start_pfn; pfn < end_pfn; ) {
 		/*
 		 * There can be holes in boot-time mem_map[]s handed to this
 		 * function.  They do not exist on hotplugged memory.
 		 */
 		if (context == MEMMAP_EARLY) {
-			if (!early_pfn_valid(pfn))
+			if (!early_pfn_valid(pfn)) {
+				pfn = next_pfn(pfn);
 				continue;
-			if (!early_pfn_in_nid(pfn, nid))
+			}
+			if (!early_pfn_in_nid(pfn, nid)) {
+				pfn++;
 				continue;
+			}
 			if (overlap_memmap_init(zone, &pfn))
 				continue;
 			if (defer_init(nid, pfn, end_pfn))
@@ -5918,16 +5939,17 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
 			cond_resched();
 		}
+		pfn++;
 	}
 }
 
 #ifdef CONFIG_ZONE_DEVICE
 void __ref memmap_init_zone_device(struct zone *zone,
 				   unsigned long start_pfn,
-				   unsigned long size,
+				   unsigned long nr_pages,
 				   struct dev_pagemap *pgmap)
 {
-	unsigned long pfn, end_pfn = start_pfn + size;
+	unsigned long pfn, end_pfn = start_pfn + nr_pages;
 	struct pglist_data *pgdat = zone->zone_pgdat;
 	struct vmem_altmap *altmap = pgmap_altmap(pgmap);
 	unsigned long zone_idx = zone_idx(zone);
@@ -5944,7 +5966,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
 	 */
 	if (altmap) {
 		start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
-		size = end_pfn - start_pfn;
+		nr_pages = end_pfn - start_pfn;
 	}
 
 	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
@@ -5991,7 +6013,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
 	}
 
 	pr_info("%s initialised %lu pages in %ums\n", __func__,
-		size, jiffies_to_msecs(jiffies - start));
+		nr_pages, jiffies_to_msecs(jiffies - start));
 }
 
 #endif
@@ -6890,10 +6912,10 @@ void __init free_area_init_node(int nid, unsigned long *zones_size,
 
 #if !defined(CONFIG_FLAT_NODE_MEM_MAP)
 /*
- * Zero all valid struct pages in range [spfn, epfn), return number of struct
- * pages zeroed
+ * Initialize all valid struct pages in the range [spfn, epfn) and mark them
+ * PageReserved(). Return the number of struct pages that were initialized.
  */
-static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn)
+static u64 __init init_unavailable_range(unsigned long spfn, unsigned long epfn)
 {
 	unsigned long pfn;
 	u64 pgcnt = 0;
@@ -6904,7 +6926,13 @@ static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn)
 				+ pageblock_nr_pages - 1;
 			continue;
 		}
-		mm_zero_struct_page(pfn_to_page(pfn));
+		/*
+		 * Use a fake node/zone (0) for now. Some of these pages
+		 * (in memblock.reserved but not in memblock.memory) will
+		 * get re-initialized via reserve_bootmem_region() later.
+		 */
+		__init_single_page(pfn_to_page(pfn), pfn, 0, 0);
+		__SetPageReserved(pfn_to_page(pfn));
 		pgcnt++;
 	}
 
@@ -6916,14 +6944,15 @@ static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn)
  * initialized by going through __init_single_page(). But, there are some
  * struct pages which are reserved in memblock allocator and their fields
  * may be accessed (for example page_to_pfn() on some configuration accesses
- * flags). We must explicitly zero those struct pages.
+ * flags). We must explicitly initialize those struct pages.
  *
  * This function also addresses a similar issue where struct pages are left
  * uninitialized because the physical address range is not covered by
  * memblock.memory or memblock.reserved. That could happen when memblock
- * layout is manually configured via memmap=.
+ * layout is manually configured via memmap=, or when the highest physical
+ * address (max_pfn) does not end on a section boundary.
  */
-void __init zero_resv_unavail(void)
+static void __init init_unavailable_mem(void)
 {
 	phys_addr_t start, end;
 	u64 i, pgcnt;
@@ -6936,10 +6965,20 @@ void __init zero_resv_unavail(void)
 	for_each_mem_range(i, &memblock.memory, NULL,
 			NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end, NULL) {
 		if (next < start)
-			pgcnt += zero_pfn_range(PFN_DOWN(next), PFN_UP(start));
+			pgcnt += init_unavailable_range(PFN_DOWN(next),
+							PFN_UP(start));
 		next = end;
 	}
-	pgcnt += zero_pfn_range(PFN_DOWN(next), max_pfn);
+
+	/*
+	 * Early sections always have a fully populated memmap for the whole
+	 * section - see pfn_valid(). If the last section has holes at the
+	 * end and that section is marked "online", the memmap will be
+	 * considered initialized. Make sure that memmap has a well defined
+	 * state.
+	 */
+	pgcnt += init_unavailable_range(PFN_DOWN(next),
+					round_up(max_pfn, PAGES_PER_SECTION));
 
 	/*
 	 * Struct pages that do not have backing memory. This could be because
@@ -6948,6 +6987,10 @@ void __init zero_resv_unavail(void)
 	if (pgcnt)
 		pr_info("Zeroed struct page in unavailable ranges: %lld pages", pgcnt);
 }
+#else
+static inline void __init init_unavailable_mem(void)
+{
+}
 #endif /* !CONFIG_FLAT_NODE_MEM_MAP */
 
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
@@ -7377,7 +7420,7 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
 	/* Initialise every node */
 	mminit_verify_pageflags_layout();
 	setup_nr_node_ids();
-	zero_resv_unavail();
+	init_unavailable_mem();
 	for_each_online_node(nid) {
 		pg_data_t *pgdat = NODE_DATA(nid);
 		free_area_init_node(nid, NULL,
@@ -7572,7 +7615,7 @@ void __init set_dma_reserve(unsigned long new_dma_reserve)
 
 void __init free_area_init(unsigned long *zones_size)
 {
-	zero_resv_unavail();
+	init_unavailable_mem();
 	free_area_init_node(0, zones_size,
 			__pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
 }
@@ -8154,20 +8197,22 @@ void *__init alloc_large_system_hash(const char *tablename,
 
 /*
  * This function checks whether pageblock includes unmovable pages or not.
- * If @count is not zero, it is okay to include less @count unmovable pages
  *
  * PageLRU check without isolation or lru_lock could race so that
  * MIGRATE_MOVABLE block might include unmovable pages. And __PageMovable
  * check without lock_page also may miss some movable non-lru pages at
  * race condition. So you can't expect this function should be exact.
+ *
+ * Returns a page without holding a reference. If the caller wants to
+ * dereference that page (e.g., dumping), it has to make sure that that it
+ * cannot get removed (e.g., via memory unplug) concurrently.
+ *
  */
-bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
-			 int migratetype, int flags)
+struct page *has_unmovable_pages(struct zone *zone, struct page *page,
+				 int migratetype, int flags)
 {
-	unsigned long found;
 	unsigned long iter = 0;
 	unsigned long pfn = page_to_pfn(page);
-	const char *reason = "unmovable page";
 
 	/*
 	 * TODO we could make this much more efficient by not checking every
@@ -8184,22 +8229,19 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		 * so consider them movable here.
 		 */
 		if (is_migrate_cma(migratetype))
-			return false;
+			return NULL;
 
-		reason = "CMA page";
-		goto unmovable;
+		return page;
 	}
 
-	for (found = 0; iter < pageblock_nr_pages; iter++) {
-		unsigned long check = pfn + iter;
-
-		if (!pfn_valid_within(check))
+	for (; iter < pageblock_nr_pages; iter++) {
+		if (!pfn_valid_within(pfn + iter))
 			continue;
 
-		page = pfn_to_page(check);
+		page = pfn_to_page(pfn + iter);
 
 		if (PageReserved(page))
-			goto unmovable;
+			return page;
 
 		/*
 		 * If the zone is movable and we have ruled out all reserved
@@ -8219,7 +8261,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 			unsigned int skip_pages;
 
 			if (!hugepage_migration_supported(page_hstate(head)))
-				goto unmovable;
+				return page;
 
 			skip_pages = compound_nr(head) - (page - head);
 			iter += skip_pages - 1;
@@ -8245,11 +8287,9 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
 			continue;
 
-		if (__PageMovable(page))
+		if (__PageMovable(page) || PageLRU(page))
 			continue;
 
-		if (!PageLRU(page))
-			found++;
 		/*
 		 * If there are RECLAIMABLE pages, we need to check
 		 * it.  But now, memory offline itself doesn't call
@@ -8263,15 +8303,9 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		 * is set to both of a memory hole page and a _used_ kernel
 		 * page at boot.
 		 */
-		if (found > count)
-			goto unmovable;
+		return page;
 	}
-	return false;
-unmovable:
-	WARN_ON_ONCE(zone_idx(zone) == ZONE_MOVABLE);
-	if (flags & REPORT_FAILURE)
-		dump_page(pfn_to_page(pfn + iter), reason);
-	return true;
+	return NULL;
 }
 
 #ifdef CONFIG_CONTIG_ALLOC
@@ -8675,10 +8709,6 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
 		BUG_ON(!PageBuddy(page));
 		order = page_order(page);
 		offlined_pages += 1 << order;
-#ifdef CONFIG_DEBUG_VM
-		pr_info("remove from free list %lx %d %lx\n",
-			pfn, 1 << order, end_pfn);
-#endif
 		del_page_from_free_area(page, &zone->free_area[order]);
 		pfn += (1 << order);
 	}
diff --git a/mm/page_io.c b/mm/page_io.c
index 3a198deb8bb1..76965be1d40e 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -177,8 +177,9 @@ int generic_swapfile_activate(struct swap_info_struct *sis,
 
 		cond_resched();
 
-		first_block = bmap(inode, probe_block);
-		if (first_block == 0)
+		first_block = probe_block;
+		ret = bmap(inode, &first_block);
+		if (ret || !first_block)
 			goto bad_bmap;
 
 		/*
@@ -193,9 +194,11 @@ int generic_swapfile_activate(struct swap_info_struct *sis,
 					block_in_page++) {
 			sector_t block;
 
-			block = bmap(inode, probe_block + block_in_page);
-			if (block == 0)
+			block = probe_block + block_in_page;
+			ret = bmap(inode, &block);
+			if (ret || !block)
 				goto bad_bmap;
+
 			if (block != first_block + block_in_page) {
 				/* Discontiguity */
 				probe_block++;
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 04ee1663cdbe..a9fd7c740c23 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -17,10 +17,9 @@
 
 static int set_migratetype_isolate(struct page *page, int migratetype, int isol_flags)
 {
+	struct page *unmovable = NULL;
 	struct zone *zone;
-	unsigned long flags, pfn;
-	struct memory_isolate_notify arg;
-	int notifier_ret;
+	unsigned long flags;
 	int ret = -EBUSY;
 
 	zone = page_zone(page);
@@ -35,41 +34,12 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
 	if (is_migrate_isolate_page(page))
 		goto out;
 
-	pfn = page_to_pfn(page);
-	arg.start_pfn = pfn;
-	arg.nr_pages = pageblock_nr_pages;
-	arg.pages_found = 0;
-
-	/*
-	 * It may be possible to isolate a pageblock even if the
-	 * migratetype is not MIGRATE_MOVABLE. The memory isolation
-	 * notifier chain is used by balloon drivers to return the
-	 * number of pages in a range that are held by the balloon
-	 * driver to shrink memory. If all the pages are accounted for
-	 * by balloons, are free, or on the LRU, isolation can continue.
-	 * Later, for example, when memory hotplug notifier runs, these
-	 * pages reported as "can be isolated" should be isolated(freed)
-	 * by the balloon driver through the memory notifier chain.
-	 */
-	notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);
-	notifier_ret = notifier_to_errno(notifier_ret);
-	if (notifier_ret)
-		goto out;
 	/*
 	 * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.
 	 * We just check MOVABLE pages.
 	 */
-	if (!has_unmovable_pages(zone, page, arg.pages_found, migratetype,
-				 isol_flags))
-		ret = 0;
-
-	/*
-	 * immobile means "not-on-lru" pages. If immobile is larger than
-	 * removable-by-driver pages reported by notifier, we'll fail.
-	 */
-
-out:
-	if (!ret) {
+	unmovable = has_unmovable_pages(zone, page, migratetype, isol_flags);
+	if (!unmovable) {
 		unsigned long nr_pages;
 		int mt = get_pageblock_migratetype(page);
 
@@ -79,11 +49,24 @@ out:
 									NULL);
 
 		__mod_zone_freepage_state(zone, -nr_pages, mt);
+		ret = 0;
 	}
 
+out:
 	spin_unlock_irqrestore(&zone->lock, flags);
-	if (!ret)
+	if (!ret) {
 		drain_all_pages(zone);
+	} else {
+		WARN_ON_ONCE(zone_idx(zone) == ZONE_MOVABLE);
+
+		if ((isol_flags & REPORT_FAILURE) && unmovable)
+			/*
+			 * printk() with zone->lock held will likely trigger a
+			 * lockdep splat, so defer it here.
+			 */
+			dump_page(unmovable, "unmovable page");
+	}
+
 	return ret;
 }
 
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index eff4b4520c8d..719c35246cfa 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -52,12 +52,16 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw)
 	return true;
 }
 
-static inline bool pfn_in_hpage(struct page *hpage, unsigned long pfn)
+static inline bool pfn_is_match(struct page *page, unsigned long pfn)
 {
-	unsigned long hpage_pfn = page_to_pfn(hpage);
+	unsigned long page_pfn = page_to_pfn(page);
+
+	/* normal page and hugetlbfs page */
+	if (!PageTransCompound(page) || PageHuge(page))
+		return page_pfn == pfn;
 
 	/* THP can be referenced by any subpage */
-	return pfn >= hpage_pfn && pfn - hpage_pfn < hpage_nr_pages(hpage);
+	return pfn >= page_pfn && pfn - page_pfn < hpage_nr_pages(page);
 }
 
 /**
@@ -108,7 +112,7 @@ static bool check_pte(struct page_vma_mapped_walk *pvmw)
 		pfn = pte_pfn(*pvmw->pte);
 	}
 
-	return pfn_in_hpage(pvmw->page, pfn);
+	return pfn_is_match(pvmw->page, pfn);
 }
 
 /**
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index ea0b9e606ad1..928df1638c30 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -4,26 +4,57 @@
 #include <linux/sched.h>
 #include <linux/hugetlb.h>
 
-static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-			  struct mm_walk *walk)
+/*
+ * We want to know the real level where a entry is located ignoring any
+ * folding of levels which may be happening. For example if p4d is folded then
+ * a missing entry found at level 1 (p4d) is actually at level 0 (pgd).
+ */
+static int real_depth(int depth)
+{
+	if (depth == 3 && PTRS_PER_PMD == 1)
+		depth = 2;
+	if (depth == 2 && PTRS_PER_PUD == 1)
+		depth = 1;
+	if (depth == 1 && PTRS_PER_P4D == 1)
+		depth = 0;
+	return depth;
+}
+
+static int walk_pte_range_inner(pte_t *pte, unsigned long addr,
+				unsigned long end, struct mm_walk *walk)
 {
-	pte_t *pte;
-	int err = 0;
 	const struct mm_walk_ops *ops = walk->ops;
-	spinlock_t *ptl;
+	int err = 0;
 
-	pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
 	for (;;) {
 		err = ops->pte_entry(pte, addr, addr + PAGE_SIZE, walk);
 		if (err)
 		       break;
-		addr += PAGE_SIZE;
-		if (addr == end)
+		if (addr >= end - PAGE_SIZE)
 			break;
+		addr += PAGE_SIZE;
 		pte++;
 	}
+	return err;
+}
+
+static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+			  struct mm_walk *walk)
+{
+	pte_t *pte;
+	int err = 0;
+	spinlock_t *ptl;
+
+	if (walk->no_vma) {
+		pte = pte_offset_map(pmd, addr);
+		err = walk_pte_range_inner(pte, addr, end, walk);
+		pte_unmap(pte);
+	} else {
+		pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
+		err = walk_pte_range_inner(pte, addr, end, walk);
+		pte_unmap_unlock(pte, ptl);
+	}
 
-	pte_unmap_unlock(pte, ptl);
 	return err;
 }
 
@@ -34,18 +65,22 @@ static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 	unsigned long next;
 	const struct mm_walk_ops *ops = walk->ops;
 	int err = 0;
+	int depth = real_depth(3);
 
 	pmd = pmd_offset(pud, addr);
 	do {
 again:
 		next = pmd_addr_end(addr, end);
-		if (pmd_none(*pmd) || !walk->vma) {
+		if (pmd_none(*pmd) || (!walk->vma && !walk->no_vma)) {
 			if (ops->pte_hole)
-				err = ops->pte_hole(addr, next, walk);
+				err = ops->pte_hole(addr, next, depth, walk);
 			if (err)
 				break;
 			continue;
 		}
+
+		walk->action = ACTION_SUBTREE;
+
 		/*
 		 * This implies that each ->pmd_entry() handler
 		 * needs to know about pmd_trans_huge() pmds
@@ -55,16 +90,24 @@ again:
 		if (err)
 			break;
 
+		if (walk->action == ACTION_AGAIN)
+			goto again;
+
 		/*
 		 * Check this here so we only break down trans_huge
 		 * pages when we _need_ to
 		 */
-		if (!ops->pte_entry)
+		if ((!walk->vma && (pmd_leaf(*pmd) || !pmd_present(*pmd))) ||
+		    walk->action == ACTION_CONTINUE ||
+		    !(ops->pte_entry))
 			continue;
 
-		split_huge_pmd(walk->vma, pmd, addr);
-		if (pmd_trans_unstable(pmd))
-			goto again;
+		if (walk->vma) {
+			split_huge_pmd(walk->vma, pmd, addr);
+			if (pmd_trans_unstable(pmd))
+				goto again;
+		}
+
 		err = walk_pte_range(pmd, addr, next, walk);
 		if (err)
 			break;
@@ -80,37 +123,41 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
 	unsigned long next;
 	const struct mm_walk_ops *ops = walk->ops;
 	int err = 0;
+	int depth = real_depth(2);
 
 	pud = pud_offset(p4d, addr);
 	do {
  again:
 		next = pud_addr_end(addr, end);
-		if (pud_none(*pud) || !walk->vma) {
+		if (pud_none(*pud) || (!walk->vma && !walk->no_vma)) {
 			if (ops->pte_hole)
-				err = ops->pte_hole(addr, next, walk);
+				err = ops->pte_hole(addr, next, depth, walk);
 			if (err)
 				break;
 			continue;
 		}
 
-		if (ops->pud_entry) {
-			spinlock_t *ptl = pud_trans_huge_lock(pud, walk->vma);
+		walk->action = ACTION_SUBTREE;
 
-			if (ptl) {
-				err = ops->pud_entry(pud, addr, next, walk);
-				spin_unlock(ptl);
-				if (err)
-					break;
-				continue;
-			}
-		}
+		if (ops->pud_entry)
+			err = ops->pud_entry(pud, addr, next, walk);
+		if (err)
+			break;
+
+		if (walk->action == ACTION_AGAIN)
+			goto again;
 
-		split_huge_pud(walk->vma, pud, addr);
+		if ((!walk->vma && (pud_leaf(*pud) || !pud_present(*pud))) ||
+		    walk->action == ACTION_CONTINUE ||
+		    !(ops->pmd_entry || ops->pte_entry))
+			continue;
+
+		if (walk->vma)
+			split_huge_pud(walk->vma, pud, addr);
 		if (pud_none(*pud))
 			goto again;
 
-		if (ops->pmd_entry || ops->pte_entry)
-			err = walk_pmd_range(pud, addr, next, walk);
+		err = walk_pmd_range(pud, addr, next, walk);
 		if (err)
 			break;
 	} while (pud++, addr = next, addr != end);
@@ -125,18 +172,24 @@ static int walk_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 	unsigned long next;
 	const struct mm_walk_ops *ops = walk->ops;
 	int err = 0;
+	int depth = real_depth(1);
 
 	p4d = p4d_offset(pgd, addr);
 	do {
 		next = p4d_addr_end(addr, end);
 		if (p4d_none_or_clear_bad(p4d)) {
 			if (ops->pte_hole)
-				err = ops->pte_hole(addr, next, walk);
+				err = ops->pte_hole(addr, next, depth, walk);
 			if (err)
 				break;
 			continue;
 		}
-		if (ops->pmd_entry || ops->pte_entry)
+		if (ops->p4d_entry) {
+			err = ops->p4d_entry(p4d, addr, next, walk);
+			if (err)
+				break;
+		}
+		if (ops->pud_entry || ops->pmd_entry || ops->pte_entry)
 			err = walk_pud_range(p4d, addr, next, walk);
 		if (err)
 			break;
@@ -153,17 +206,26 @@ static int walk_pgd_range(unsigned long addr, unsigned long end,
 	const struct mm_walk_ops *ops = walk->ops;
 	int err = 0;
 
-	pgd = pgd_offset(walk->mm, addr);
+	if (walk->pgd)
+		pgd = walk->pgd + pgd_index(addr);
+	else
+		pgd = pgd_offset(walk->mm, addr);
 	do {
 		next = pgd_addr_end(addr, end);
 		if (pgd_none_or_clear_bad(pgd)) {
 			if (ops->pte_hole)
-				err = ops->pte_hole(addr, next, walk);
+				err = ops->pte_hole(addr, next, 0, walk);
 			if (err)
 				break;
 			continue;
 		}
-		if (ops->pmd_entry || ops->pte_entry)
+		if (ops->pgd_entry) {
+			err = ops->pgd_entry(pgd, addr, next, walk);
+			if (err)
+				break;
+		}
+		if (ops->p4d_entry || ops->pud_entry || ops->pmd_entry ||
+		    ops->pte_entry)
 			err = walk_p4d_range(pgd, addr, next, walk);
 		if (err)
 			break;
@@ -199,7 +261,7 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end,
 		if (pte)
 			err = ops->hugetlb_entry(pte, hmask, addr, next, walk);
 		else if (ops->pte_hole)
-			err = ops->pte_hole(addr, next, walk);
+			err = ops->pte_hole(addr, next, -1, walk);
 
 		if (err)
 			break;
@@ -243,7 +305,7 @@ static int walk_page_test(unsigned long start, unsigned long end,
 	if (vma->vm_flags & VM_PFNMAP) {
 		int err = 1;
 		if (ops->pte_hole)
-			err = ops->pte_hole(start, end, walk);
+			err = ops->pte_hole(start, end, -1, walk);
 		return err ? err : 1;
 	}
 	return 0;
@@ -369,6 +431,33 @@ int walk_page_range(struct mm_struct *mm, unsigned long start,
 	return err;
 }
 
+/*
+ * Similar to walk_page_range() but can walk any page tables even if they are
+ * not backed by VMAs. Because 'unusual' entries may be walked this function
+ * will also not lock the PTEs for the pte_entry() callback. This is useful for
+ * walking the kernel pages tables or page tables for firmware.
+ */
+int walk_page_range_novma(struct mm_struct *mm, unsigned long start,
+			  unsigned long end, const struct mm_walk_ops *ops,
+			  pgd_t *pgd,
+			  void *private)
+{
+	struct mm_walk walk = {
+		.ops		= ops,
+		.mm		= mm,
+		.pgd		= pgd,
+		.private	= private,
+		.no_vma		= true
+	};
+
+	if (start >= end || !walk.mm)
+		return -EINVAL;
+
+	lockdep_assert_held(&walk.mm->mmap_sem);
+
+	return __walk_page_range(start, end, &walk);
+}
+
 int walk_page_vma(struct vm_area_struct *vma, const struct mm_walk_ops *ops,
 		void *private)
 {
diff --git a/mm/percpu.c b/mm/percpu.c
index 7e06a1e58720..e9844086b236 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -270,33 +270,6 @@ static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk,
 	       pcpu_unit_page_offset(cpu, page_idx);
 }
 
-static void pcpu_next_unpop(unsigned long *bitmap, int *rs, int *re, int end)
-{
-	*rs = find_next_zero_bit(bitmap, end, *rs);
-	*re = find_next_bit(bitmap, end, *rs + 1);
-}
-
-static void pcpu_next_pop(unsigned long *bitmap, int *rs, int *re, int end)
-{
-	*rs = find_next_bit(bitmap, end, *rs);
-	*re = find_next_zero_bit(bitmap, end, *rs + 1);
-}
-
-/*
- * Bitmap region iterators.  Iterates over the bitmap between
- * [@start, @end) in @chunk.  @rs and @re should be integer variables
- * and will be set to start and end index of the current free region.
- */
-#define pcpu_for_each_unpop_region(bitmap, rs, re, start, end)		     \
-	for ((rs) = (start), pcpu_next_unpop((bitmap), &(rs), &(re), (end)); \
-	     (rs) < (re);						     \
-	     (rs) = (re) + 1, pcpu_next_unpop((bitmap), &(rs), &(re), (end)))
-
-#define pcpu_for_each_pop_region(bitmap, rs, re, start, end)		     \
-	for ((rs) = (start), pcpu_next_pop((bitmap), &(rs), &(re), (end));   \
-	     (rs) < (re);						     \
-	     (rs) = (re) + 1, pcpu_next_pop((bitmap), &(rs), &(re), (end)))
-
 /*
  * The following are helper functions to help access bitmaps and convert
  * between bitmap offsets to address offsets.
@@ -732,9 +705,8 @@ static void pcpu_chunk_refresh_hint(struct pcpu_chunk *chunk, bool full_scan)
 	}
 
 	bits = 0;
-	pcpu_for_each_md_free_region(chunk, bit_off, bits) {
+	pcpu_for_each_md_free_region(chunk, bit_off, bits)
 		pcpu_block_update(chunk_md, bit_off, bit_off + bits);
-	}
 }
 
 /**
@@ -749,7 +721,7 @@ static void pcpu_block_refresh_hint(struct pcpu_chunk *chunk, int index)
 {
 	struct pcpu_block_md *block = chunk->md_blocks + index;
 	unsigned long *alloc_map = pcpu_index_alloc_map(chunk, index);
-	int rs, re, start;	/* region start, region end */
+	unsigned int rs, re, start;	/* region start, region end */
 
 	/* promote scan_hint to contig_hint */
 	if (block->scan_hint) {
@@ -765,10 +737,9 @@ static void pcpu_block_refresh_hint(struct pcpu_chunk *chunk, int index)
 	block->right_free = 0;
 
 	/* iterate over free areas and update the contig hints */
-	pcpu_for_each_unpop_region(alloc_map, rs, re, start,
-				   PCPU_BITMAP_BLOCK_BITS) {
+	bitmap_for_each_clear_region(alloc_map, rs, re, start,
+				     PCPU_BITMAP_BLOCK_BITS)
 		pcpu_block_update(block, rs, re);
-	}
 }
 
 /**
@@ -1041,13 +1012,13 @@ static void pcpu_block_update_hint_free(struct pcpu_chunk *chunk, int bit_off,
 static bool pcpu_is_populated(struct pcpu_chunk *chunk, int bit_off, int bits,
 			      int *next_off)
 {
-	int page_start, page_end, rs, re;
+	unsigned int page_start, page_end, rs, re;
 
 	page_start = PFN_DOWN(bit_off * PCPU_MIN_ALLOC_SIZE);
 	page_end = PFN_UP((bit_off + bits) * PCPU_MIN_ALLOC_SIZE);
 
 	rs = page_start;
-	pcpu_next_unpop(chunk->populated, &rs, &re, page_end);
+	bitmap_next_clear_region(chunk->populated, &rs, &re, page_end);
 	if (rs >= page_end)
 		return true;
 
@@ -1702,13 +1673,13 @@ area_found:
 
 	/* populate if not all pages are already there */
 	if (!is_atomic) {
-		int page_start, page_end, rs, re;
+		unsigned int page_start, page_end, rs, re;
 
 		page_start = PFN_DOWN(off);
 		page_end = PFN_UP(off + size);
 
-		pcpu_for_each_unpop_region(chunk->populated, rs, re,
-					   page_start, page_end) {
+		bitmap_for_each_clear_region(chunk->populated, rs, re,
+					     page_start, page_end) {
 			WARN_ON(chunk->immutable);
 
 			ret = pcpu_populate_chunk(chunk, rs, re, pcpu_gfp);
@@ -1858,10 +1829,10 @@ static void pcpu_balance_workfn(struct work_struct *work)
 	spin_unlock_irq(&pcpu_lock);
 
 	list_for_each_entry_safe(chunk, next, &to_free, list) {
-		int rs, re;
+		unsigned int rs, re;
 
-		pcpu_for_each_pop_region(chunk->populated, rs, re, 0,
-					 chunk->nr_pages) {
+		bitmap_for_each_set_region(chunk->populated, rs, re, 0,
+					   chunk->nr_pages) {
 			pcpu_depopulate_chunk(chunk, rs, re);
 			spin_lock_irq(&pcpu_lock);
 			pcpu_chunk_depopulated(chunk, rs, re);
@@ -1893,7 +1864,7 @@ retry_pop:
 	}
 
 	for (slot = pcpu_size_to_slot(PAGE_SIZE); slot < pcpu_nr_slots; slot++) {
-		int nr_unpop = 0, rs, re;
+		unsigned int nr_unpop = 0, rs, re;
 
 		if (!nr_to_pop)
 			break;
@@ -1910,9 +1881,9 @@ retry_pop:
 			continue;
 
 		/* @chunk can't go away while pcpu_alloc_mutex is held */
-		pcpu_for_each_unpop_region(chunk->populated, rs, re, 0,
-					   chunk->nr_pages) {
-			int nr = min(re - rs, nr_to_pop);
+		bitmap_for_each_clear_region(chunk->populated, rs, re, 0,
+					     chunk->nr_pages) {
+			int nr = min_t(int, re - rs, nr_to_pop);
 
 			ret = pcpu_populate_chunk(chunk, rs, rs + nr, gfp);
 			if (!ret) {
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index 357aa7bef6c0..de41e830cdac 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -42,12 +42,11 @@ static int process_vm_rw_pages(struct page **pages,
 		if (copy > len)
 			copy = len;
 
-		if (vm_write) {
+		if (vm_write)
 			copied = copy_page_from_iter(page, offset, copy, iter);
-			set_page_dirty_lock(page);
-		} else {
+		else
 			copied = copy_page_to_iter(page, offset, copy, iter);
-		}
+
 		len -= copied;
 		if (copied < copy && iov_iter_count(iter))
 			return -EFAULT;
@@ -96,7 +95,7 @@ static int process_vm_rw_single_vec(unsigned long addr,
 		flags |= FOLL_WRITE;
 
 	while (!rc && nr_pages && iov_iter_count(iter)) {
-		int pages = min(nr_pages, max_pages_per_loop);
+		int pinned_pages = min(nr_pages, max_pages_per_loop);
 		int locked = 1;
 		size_t bytes;
 
@@ -106,14 +105,15 @@ static int process_vm_rw_single_vec(unsigned long addr,
 		 * current/current->mm
 		 */
 		down_read(&mm->mmap_sem);
-		pages = get_user_pages_remote(task, mm, pa, pages, flags,
-					      process_pages, NULL, &locked);
+		pinned_pages = pin_user_pages_remote(task, mm, pa, pinned_pages,
+						     flags, process_pages,
+						     NULL, &locked);
 		if (locked)
 			up_read(&mm->mmap_sem);
-		if (pages <= 0)
+		if (pinned_pages <= 0)
 			return -EFAULT;
 
-		bytes = pages * PAGE_SIZE - start_offset;
+		bytes = pinned_pages * PAGE_SIZE - start_offset;
 		if (bytes > len)
 			bytes = len;
 
@@ -122,10 +122,12 @@ static int process_vm_rw_single_vec(unsigned long addr,
 					 vm_write);
 		len -= bytes;
 		start_offset = 0;
-		nr_pages -= pages;
-		pa += pages * PAGE_SIZE;
-		while (pages)
-			put_page(process_pages[--pages]);
+		nr_pages -= pinned_pages;
+		pa += pinned_pages * PAGE_SIZE;
+
+		/* If vm_write is set, the pages need to be made dirty: */
+		unpin_user_pages_dirty_lock(process_pages, pinned_pages,
+					    vm_write);
 	}
 
 	return rc;
diff --git a/mm/ptdump.c b/mm/ptdump.c
new file mode 100644
index 000000000000..26208d0d03b7
--- /dev/null
+++ b/mm/ptdump.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/pagewalk.h>
+#include <linux/ptdump.h>
+#include <linux/kasan.h>
+
+#ifdef CONFIG_KASAN
+/*
+ * This is an optimization for KASAN=y case. Since all kasan page tables
+ * eventually point to the kasan_early_shadow_page we could call note_page()
+ * right away without walking through lower level page tables. This saves
+ * us dozens of seconds (minutes for 5-level config) while checking for
+ * W+X mapping or reading kernel_page_tables debugfs file.
+ */
+static inline int note_kasan_page_table(struct mm_walk *walk,
+					unsigned long addr)
+{
+	struct ptdump_state *st = walk->private;
+
+	st->note_page(st, addr, 4, pte_val(kasan_early_shadow_pte[0]));
+
+	walk->action = ACTION_CONTINUE;
+
+	return 0;
+}
+#endif
+
+static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
+			    unsigned long next, struct mm_walk *walk)
+{
+	struct ptdump_state *st = walk->private;
+	pgd_t val = READ_ONCE(*pgd);
+
+#if CONFIG_PGTABLE_LEVELS > 4 && defined(CONFIG_KASAN)
+	if (pgd_page(val) == virt_to_page(lm_alias(kasan_early_shadow_p4d)))
+		return note_kasan_page_table(walk, addr);
+#endif
+
+	if (pgd_leaf(val))
+		st->note_page(st, addr, 0, pgd_val(val));
+
+	return 0;
+}
+
+static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
+			    unsigned long next, struct mm_walk *walk)
+{
+	struct ptdump_state *st = walk->private;
+	p4d_t val = READ_ONCE(*p4d);
+
+#if CONFIG_PGTABLE_LEVELS > 3 && defined(CONFIG_KASAN)
+	if (p4d_page(val) == virt_to_page(lm_alias(kasan_early_shadow_pud)))
+		return note_kasan_page_table(walk, addr);
+#endif
+
+	if (p4d_leaf(val))
+		st->note_page(st, addr, 1, p4d_val(val));
+
+	return 0;
+}
+
+static int ptdump_pud_entry(pud_t *pud, unsigned long addr,
+			    unsigned long next, struct mm_walk *walk)
+{
+	struct ptdump_state *st = walk->private;
+	pud_t val = READ_ONCE(*pud);
+
+#if CONFIG_PGTABLE_LEVELS > 2 && defined(CONFIG_KASAN)
+	if (pud_page(val) == virt_to_page(lm_alias(kasan_early_shadow_pmd)))
+		return note_kasan_page_table(walk, addr);
+#endif
+
+	if (pud_leaf(val))
+		st->note_page(st, addr, 2, pud_val(val));
+
+	return 0;
+}
+
+static int ptdump_pmd_entry(pmd_t *pmd, unsigned long addr,
+			    unsigned long next, struct mm_walk *walk)
+{
+	struct ptdump_state *st = walk->private;
+	pmd_t val = READ_ONCE(*pmd);
+
+#if defined(CONFIG_KASAN)
+	if (pmd_page(val) == virt_to_page(lm_alias(kasan_early_shadow_pte)))
+		return note_kasan_page_table(walk, addr);
+#endif
+
+	if (pmd_leaf(val))
+		st->note_page(st, addr, 3, pmd_val(val));
+
+	return 0;
+}
+
+static int ptdump_pte_entry(pte_t *pte, unsigned long addr,
+			    unsigned long next, struct mm_walk *walk)
+{
+	struct ptdump_state *st = walk->private;
+
+	st->note_page(st, addr, 4, pte_val(READ_ONCE(*pte)));
+
+	return 0;
+}
+
+static int ptdump_hole(unsigned long addr, unsigned long next,
+		       int depth, struct mm_walk *walk)
+{
+	struct ptdump_state *st = walk->private;
+
+	st->note_page(st, addr, depth, 0);
+
+	return 0;
+}
+
+static const struct mm_walk_ops ptdump_ops = {
+	.pgd_entry	= ptdump_pgd_entry,
+	.p4d_entry	= ptdump_p4d_entry,
+	.pud_entry	= ptdump_pud_entry,
+	.pmd_entry	= ptdump_pmd_entry,
+	.pte_entry	= ptdump_pte_entry,
+	.pte_hole	= ptdump_hole,
+};
+
+void ptdump_walk_pgd(struct ptdump_state *st, struct mm_struct *mm, pgd_t *pgd)
+{
+	const struct ptdump_range *range = st->range;
+
+	down_read(&mm->mmap_sem);
+	while (range->start != range->end) {
+		walk_page_range_novma(mm, range->start, range->end,
+				      &ptdump_ops, pgd, st);
+		range++;
+	}
+	up_read(&mm->mmap_sem);
+
+	/* Flush out the last page */
+	st->note_page(st, 0, -1, 0);
+}
diff --git a/mm/shmem.c b/mm/shmem.c
index 8793e8cc1a48..c8f7540ef048 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -3381,9 +3381,19 @@ enum shmem_param {
 	Opt_uid,
 };
 
-static const struct fs_parameter_spec shmem_param_specs[] = {
+static const struct constant_table shmem_param_enums_huge[] = {
+	{"never",	SHMEM_HUGE_NEVER },
+	{"always",	SHMEM_HUGE_ALWAYS },
+	{"within_size",	SHMEM_HUGE_WITHIN_SIZE },
+	{"advise",	SHMEM_HUGE_ADVISE },
+	{"deny",	SHMEM_HUGE_DENY },
+	{"force",	SHMEM_HUGE_FORCE },
+	{}
+};
+
+const struct fs_parameter_spec shmem_fs_parameters[] = {
 	fsparam_u32   ("gid",		Opt_gid),
-	fsparam_enum  ("huge",		Opt_huge),
+	fsparam_enum  ("huge",		Opt_huge,  shmem_param_enums_huge),
 	fsparam_u32oct("mode",		Opt_mode),
 	fsparam_string("mpol",		Opt_mpol),
 	fsparam_string("nr_blocks",	Opt_nr_blocks),
@@ -3393,20 +3403,6 @@ static const struct fs_parameter_spec shmem_param_specs[] = {
 	{}
 };
 
-static const struct fs_parameter_enum shmem_param_enums[] = {
-	{ Opt_huge,	"never",	SHMEM_HUGE_NEVER },
-	{ Opt_huge,	"always",	SHMEM_HUGE_ALWAYS },
-	{ Opt_huge,	"within_size",	SHMEM_HUGE_WITHIN_SIZE },
-	{ Opt_huge,	"advise",	SHMEM_HUGE_ADVISE },
-	{}
-};
-
-const struct fs_parameter_description shmem_fs_parameters = {
-	.name		= "tmpfs",
-	.specs		= shmem_param_specs,
-	.enums		= shmem_param_enums,
-};
-
 static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param)
 {
 	struct shmem_options *ctx = fc->fs_private;
@@ -3415,7 +3411,7 @@ static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param)
 	char *rest;
 	int opt;
 
-	opt = fs_parse(fc, &shmem_fs_parameters, param, &result);
+	opt = fs_parse(fc, shmem_fs_parameters, param, &result);
 	if (opt < 0)
 		return opt;
 
@@ -3479,9 +3475,9 @@ static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param)
 	return 0;
 
 unsupported_parameter:
-	return invalf(fc, "tmpfs: Unsupported parameter '%s'", param->key);
+	return invalfc(fc, "Unsupported parameter '%s'", param->key);
 bad_value:
-	return invalf(fc, "tmpfs: Bad value for '%s'", param->key);
+	return invalfc(fc, "Bad value for '%s'", param->key);
 }
 
 static int shmem_parse_options(struct fs_context *fc, void *data)
@@ -3587,7 +3583,7 @@ static int shmem_reconfigure(struct fs_context *fc)
 	return 0;
 out:
 	spin_unlock(&sbinfo->stat_lock);
-	return invalf(fc, "tmpfs: %s", err);
+	return invalfc(fc, "%s", err);
 }
 
 static int shmem_show_options(struct seq_file *seq, struct dentry *root)
@@ -3889,7 +3885,7 @@ static struct file_system_type shmem_fs_type = {
 	.name		= "tmpfs",
 	.init_fs_context = shmem_init_fs_context,
 #ifdef CONFIG_TMPFS
-	.parameters	= &shmem_fs_parameters,
+	.parameters	= shmem_fs_parameters,
 #endif
 	.kill_sb	= kill_litter_super,
 	.fs_flags	= FS_USERNS_MOUNT,
@@ -4035,7 +4031,7 @@ bool shmem_huge_enabled(struct vm_area_struct *vma)
 static struct file_system_type shmem_fs_type = {
 	.name		= "tmpfs",
 	.init_fs_context = ramfs_init_fs_context,
-	.parameters	= &ramfs_fs_parameters,
+	.parameters	= ramfs_fs_parameters,
 	.kill_sb	= kill_litter_super,
 	.fs_flags	= FS_USERNS_MOUNT,
 };
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 0d95ddea13b0..1907cb2903c7 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -1580,18 +1580,17 @@ static int slabinfo_open(struct inode *inode, struct file *file)
 	return seq_open(file, &slabinfo_op);
 }
 
-static const struct file_operations proc_slabinfo_operations = {
-	.open		= slabinfo_open,
-	.read		= seq_read,
-	.write          = slabinfo_write,
-	.llseek		= seq_lseek,
-	.release	= seq_release,
+static const struct proc_ops slabinfo_proc_ops = {
+	.proc_open	= slabinfo_open,
+	.proc_read	= seq_read,
+	.proc_write	= slabinfo_write,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= seq_release,
 };
 
 static int __init slab_proc_init(void)
 {
-	proc_create("slabinfo", SLABINFO_RIGHTS, NULL,
-						&proc_slabinfo_operations);
+	proc_create("slabinfo", SLABINFO_RIGHTS, NULL, &slabinfo_proc_ops);
 	return 0;
 }
 module_init(slab_proc_init);
@@ -1677,28 +1676,6 @@ static __always_inline void *__do_krealloc(const void *p, size_t new_size,
 }
 
 /**
- * __krealloc - like krealloc() but don't free @p.
- * @p: object to reallocate memory for.
- * @new_size: how many bytes of memory are required.
- * @flags: the type of memory to allocate.
- *
- * This function is like krealloc() except it never frees the originally
- * allocated buffer. Use this if you don't want to free the buffer immediately
- * like, for example, with RCU.
- *
- * Return: pointer to the allocated memory or %NULL in case of error
- */
-void *__krealloc(const void *p, size_t new_size, gfp_t flags)
-{
-	if (unlikely(!new_size))
-		return ZERO_SIZE_PTR;
-
-	return __do_krealloc(p, new_size, flags);
-
-}
-EXPORT_SYMBOL(__krealloc);
-
-/**
  * krealloc - reallocate memory. The contents will remain unchanged.
  * @p: object to reallocate memory for.
  * @new_size: how many bytes of memory are required.
diff --git a/mm/slub.c b/mm/slub.c
index 8eafccf75940..17dc00e33115 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -439,19 +439,38 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
 }
 
 #ifdef CONFIG_SLUB_DEBUG
+static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)];
+static DEFINE_SPINLOCK(object_map_lock);
+
 /*
  * Determine a map of object in use on a page.
  *
  * Node listlock must be held to guarantee that the page does
  * not vanish from under us.
  */
-static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map)
+static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 {
 	void *p;
 	void *addr = page_address(page);
 
+	VM_BUG_ON(!irqs_disabled());
+
+	spin_lock(&object_map_lock);
+
+	bitmap_zero(object_map, page->objects);
+
 	for (p = page->freelist; p; p = get_freepointer(s, p))
-		set_bit(slab_index(p, s, addr), map);
+		set_bit(slab_index(p, s, addr), object_map);
+
+	return object_map;
+}
+
+static void put_map(unsigned long *map)
+{
+	VM_BUG_ON(map != object_map);
+	lockdep_assert_held(&object_map_lock);
+
+	spin_unlock(&object_map_lock);
 }
 
 static inline unsigned int size_from_object(struct kmem_cache *s)
@@ -1964,7 +1983,7 @@ static void *get_partial(struct kmem_cache *s, gfp_t flags, int node,
 	return get_any_partial(s, flags, c);
 }
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 /*
  * Calculate the next globally unique transaction for disambiguiation
  * during cmpxchg. The transactions start with the cpu number and are then
@@ -2009,7 +2028,7 @@ static inline void note_cmpxchg_failure(const char *n,
 
 	pr_info("%s %s: cmpxchg redo ", n, s->name);
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 	if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))
 		pr_warn("due to cpu change %d -> %d\n",
 			tid_to_cpu(tid), tid_to_cpu(actual_tid));
@@ -2341,7 +2360,7 @@ static bool has_cpu_slab(int cpu, void *info)
 
 static void flush_all(struct kmem_cache *s)
 {
-	on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC);
+	on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1);
 }
 
 /*
@@ -2637,7 +2656,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 	unsigned long flags;
 
 	local_irq_save(flags);
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 	/*
 	 * We may have been preempted and rescheduled on a different
 	 * cpu before disabling interrupts. Need to reload cpu area
@@ -2691,13 +2710,13 @@ redo:
 	 * as we end up on the original cpu again when doing the cmpxchg.
 	 *
 	 * We should guarantee that tid and kmem_cache are retrieved on
-	 * the same cpu. It could be different if CONFIG_PREEMPT so we need
+	 * the same cpu. It could be different if CONFIG_PREEMPTION so we need
 	 * to check if it is matched or not.
 	 */
 	do {
 		tid = this_cpu_read(s->cpu_slab->tid);
 		c = raw_cpu_ptr(s->cpu_slab);
-	} while (IS_ENABLED(CONFIG_PREEMPT) &&
+	} while (IS_ENABLED(CONFIG_PREEMPTION) &&
 		 unlikely(tid != READ_ONCE(c->tid)));
 
 	/*
@@ -2971,7 +2990,7 @@ redo:
 	do {
 		tid = this_cpu_read(s->cpu_slab->tid);
 		c = raw_cpu_ptr(s->cpu_slab);
-	} while (IS_ENABLED(CONFIG_PREEMPT) &&
+	} while (IS_ENABLED(CONFIG_PREEMPTION) &&
 		 unlikely(tid != READ_ONCE(c->tid)));
 
 	/* Same with comment on barrier() in slab_alloc_node() */
@@ -3675,13 +3694,12 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
 #ifdef CONFIG_SLUB_DEBUG
 	void *addr = page_address(page);
 	void *p;
-	unsigned long *map = bitmap_zalloc(page->objects, GFP_ATOMIC);
-	if (!map)
-		return;
+	unsigned long *map;
+
 	slab_err(s, page, text, s->name);
 	slab_lock(page);
 
-	get_map(s, page, map);
+	map = get_map(s, page);
 	for_each_object(p, s, addr, page->objects) {
 
 		if (!test_bit(slab_index(p, s, addr), map)) {
@@ -3689,8 +3707,9 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
 			print_tracking(s, p);
 		}
 	}
+	put_map(map);
+
 	slab_unlock(page);
-	bitmap_free(map);
 #endif
 }
 
@@ -4384,19 +4403,19 @@ static int count_total(struct page *page)
 #endif
 
 #ifdef CONFIG_SLUB_DEBUG
-static void validate_slab(struct kmem_cache *s, struct page *page,
-						unsigned long *map)
+static void validate_slab(struct kmem_cache *s, struct page *page)
 {
 	void *p;
 	void *addr = page_address(page);
+	unsigned long *map;
+
+	slab_lock(page);
 
 	if (!check_slab(s, page) || !on_freelist(s, page, NULL))
-		return;
+		goto unlock;
 
 	/* Now we know that a valid freelist exists */
-	bitmap_zero(map, page->objects);
-
-	get_map(s, page, map);
+	map = get_map(s, page);
 	for_each_object(p, s, addr, page->objects) {
 		u8 val = test_bit(slab_index(p, s, addr), map) ?
 			 SLUB_RED_INACTIVE : SLUB_RED_ACTIVE;
@@ -4404,18 +4423,13 @@ static void validate_slab(struct kmem_cache *s, struct page *page,
 		if (!check_object(s, page, p, val))
 			break;
 	}
-}
-
-static void validate_slab_slab(struct kmem_cache *s, struct page *page,
-						unsigned long *map)
-{
-	slab_lock(page);
-	validate_slab(s, page, map);
+	put_map(map);
+unlock:
 	slab_unlock(page);
 }
 
 static int validate_slab_node(struct kmem_cache *s,
-		struct kmem_cache_node *n, unsigned long *map)
+		struct kmem_cache_node *n)
 {
 	unsigned long count = 0;
 	struct page *page;
@@ -4424,7 +4438,7 @@ static int validate_slab_node(struct kmem_cache *s,
 	spin_lock_irqsave(&n->list_lock, flags);
 
 	list_for_each_entry(page, &n->partial, slab_list) {
-		validate_slab_slab(s, page, map);
+		validate_slab(s, page);
 		count++;
 	}
 	if (count != n->nr_partial)
@@ -4435,7 +4449,7 @@ static int validate_slab_node(struct kmem_cache *s,
 		goto out;
 
 	list_for_each_entry(page, &n->full, slab_list) {
-		validate_slab_slab(s, page, map);
+		validate_slab(s, page);
 		count++;
 	}
 	if (count != atomic_long_read(&n->nr_slabs))
@@ -4452,15 +4466,11 @@ static long validate_slab_cache(struct kmem_cache *s)
 	int node;
 	unsigned long count = 0;
 	struct kmem_cache_node *n;
-	unsigned long *map = bitmap_alloc(oo_objects(s->max), GFP_KERNEL);
-
-	if (!map)
-		return -ENOMEM;
 
 	flush_all(s);
 	for_each_kmem_cache_node(s, node, n)
-		count += validate_slab_node(s, n, map);
-	bitmap_free(map);
+		count += validate_slab_node(s, n);
+
 	return count;
 }
 /*
@@ -4590,18 +4600,17 @@ static int add_location(struct loc_track *t, struct kmem_cache *s,
 }
 
 static void process_slab(struct loc_track *t, struct kmem_cache *s,
-		struct page *page, enum track_item alloc,
-		unsigned long *map)
+		struct page *page, enum track_item alloc)
 {
 	void *addr = page_address(page);
 	void *p;
+	unsigned long *map;
 
-	bitmap_zero(map, page->objects);
-	get_map(s, page, map);
-
+	map = get_map(s, page);
 	for_each_object(p, s, addr, page->objects)
 		if (!test_bit(slab_index(p, s, addr), map))
 			add_location(t, s, get_track(s, p, alloc));
+	put_map(map);
 }
 
 static int list_locations(struct kmem_cache *s, char *buf,
@@ -4612,11 +4621,9 @@ static int list_locations(struct kmem_cache *s, char *buf,
 	struct loc_track t = { 0, 0, NULL };
 	int node;
 	struct kmem_cache_node *n;
-	unsigned long *map = bitmap_alloc(oo_objects(s->max), GFP_KERNEL);
 
-	if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
-				     GFP_KERNEL)) {
-		bitmap_free(map);
+	if (!alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
+			     GFP_KERNEL)) {
 		return sprintf(buf, "Out of memory\n");
 	}
 	/* Push back cpu slabs */
@@ -4631,9 +4638,9 @@ static int list_locations(struct kmem_cache *s, char *buf,
 
 		spin_lock_irqsave(&n->list_lock, flags);
 		list_for_each_entry(page, &n->partial, slab_list)
-			process_slab(&t, s, page, alloc, map);
+			process_slab(&t, s, page, alloc);
 		list_for_each_entry(page, &n->full, slab_list)
-			process_slab(&t, s, page, alloc, map);
+			process_slab(&t, s, page, alloc);
 		spin_unlock_irqrestore(&n->list_lock, flags);
 	}
 
@@ -4682,7 +4689,6 @@ static int list_locations(struct kmem_cache *s, char *buf,
 	}
 
 	free_loc_track(&t);
-	bitmap_free(map);
 	if (!t.count)
 		len += sprintf(buf, "No data\n");
 	return len;
diff --git a/mm/sparse.c b/mm/sparse.c
index 3822ecbd8a1f..596b2a45b100 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -198,16 +198,6 @@ static void section_mark_present(struct mem_section *ms)
 	ms->section_mem_map |= SECTION_MARKED_PRESENT;
 }
 
-static inline unsigned long next_present_section_nr(unsigned long section_nr)
-{
-	do {
-		section_nr++;
-		if (present_section_nr(section_nr))
-			return section_nr;
-	} while ((section_nr <= __highest_present_section_nr));
-
-	return -1;
-}
 #define for_each_present_section_nr(start, section_nr)		\
 	for (section_nr = next_present_section_nr(start-1);	\
 	     ((section_nr != -1) &&				\
@@ -789,7 +779,7 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
 			ms->usage = NULL;
 		}
 		memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
-		ms->section_mem_map = sparse_encode_mem_map(NULL, section_nr);
+		ms->section_mem_map = (unsigned long)NULL;
 	}
 
 	if (section_is_early && memmap)
@@ -886,7 +876,7 @@ int __meminit sparse_add_section(int nid, unsigned long start_pfn,
 	 * Poison uninitialized struct pages in order to catch invalid flags
 	 * combinations.
 	 */
-	page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * nr_pages);
+	page_init_poison(memmap, sizeof(struct page) * nr_pages);
 
 	ms = __nr_to_section(section_nr);
 	set_section_nid(section_nr, nid);
diff --git a/mm/swap.c b/mm/swap.c
index 5341ae93861f..cf39d24ada2a 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -813,8 +813,10 @@ void release_pages(struct page **pages, int nr)
 			 * processing, and instead, expect a call to
 			 * put_page_testzero().
 			 */
-			if (put_devmap_managed_page(page))
+			if (page_is_devmap_managed(page)) {
+				put_devmap_managed_page(page);
 				continue;
+			}
 		}
 
 		page = compound_head(page);
@@ -1102,3 +1104,26 @@ void __init swap_setup(void)
 	 * _really_ don't want to cluster much more
 	 */
 }
+
+#ifdef CONFIG_DEV_PAGEMAP_OPS
+void put_devmap_managed_page(struct page *page)
+{
+	int count;
+
+	if (WARN_ON_ONCE(!page_is_devmap_managed(page)))
+		return;
+
+	count = page_ref_dec_return(page);
+
+	/*
+	 * devmap page refcounts are 1-based, rather than 0-based: if
+	 * refcount is 1, then the page is free and the refcount is
+	 * stable because nobody holds a reference on the page.
+	 */
+	if (count == 1)
+		free_devmap_managed_page(page);
+	else if (!count)
+		__put_page(page);
+}
+EXPORT_SYMBOL(put_devmap_managed_page);
+#endif
diff --git a/mm/swapfile.c b/mm/swapfile.c
index bb3261d45b6a..b2a2e45c9a36 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2737,10 +2737,10 @@ static void *swap_next(struct seq_file *swap, void *v, loff_t *pos)
 	else
 		type = si->type + 1;
 
+	++(*pos);
 	for (; (si = swap_type_to_swap_info(type)); type++) {
 		if (!(si->flags & SWP_USED) || !si->swap_map)
 			continue;
-		++*pos;
 		return si;
 	}
 
@@ -2796,17 +2796,17 @@ static int swaps_open(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static const struct file_operations proc_swaps_operations = {
-	.open		= swaps_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= seq_release,
-	.poll		= swaps_poll,
+static const struct proc_ops swaps_proc_ops = {
+	.proc_open	= swaps_open,
+	.proc_read	= seq_read,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= seq_release,
+	.proc_poll	= swaps_poll,
 };
 
 static int __init procswaps_init(void)
 {
-	proc_create("swaps", 0, NULL, &proc_swaps_operations);
+	proc_create("swaps", 0, NULL, &swaps_proc_ops);
 	return 0;
 }
 __initcall(procswaps_init);
@@ -3157,7 +3157,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 	mapping = swap_file->f_mapping;
 	inode = mapping->host;
 
-	/* If S_ISREG(inode->i_mode) will do inode_lock(inode); */
+	/* will take i_rwsem; */
 	error = claim_swapfile(p, inode);
 	if (unlikely(error))
 		goto bad_swap;
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b29ad17edcf5..1f46c3b86f9f 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -41,6 +41,14 @@
 
 #include "internal.h"
 
+bool is_vmalloc_addr(const void *x)
+{
+	unsigned long addr = (unsigned long)x;
+
+	return addr >= VMALLOC_START && addr < VMALLOC_END;
+}
+EXPORT_SYMBOL(is_vmalloc_addr);
+
 struct vfree_deferred {
 	struct llist_head list;
 	struct work_struct wq;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 572fb17c6273..876370565455 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -146,20 +146,6 @@ struct scan_control {
 	struct reclaim_state reclaim_state;
 };
 
-#ifdef ARCH_HAS_PREFETCH
-#define prefetch_prev_lru_page(_page, _base, _field)			\
-	do {								\
-		if ((_page)->lru.prev != _base) {			\
-			struct page *prev;				\
-									\
-			prev = lru_to_page(&(_page->lru));		\
-			prefetch(&prev->_field);			\
-		}							\
-	} while (0)
-#else
-#define prefetch_prev_lru_page(_page, _base, _field) do { } while (0)
-#endif
-
 #ifdef ARCH_HAS_PREFETCHW
 #define prefetchw_prev_lru_page(_page, _base, _field)			\
 	do {								\
@@ -2429,10 +2415,13 @@ out:
 			/*
 			 * Scan types proportional to swappiness and
 			 * their relative recent reclaim efficiency.
-			 * Make sure we don't miss the last page
-			 * because of a round-off error.
+			 * Make sure we don't miss the last page on
+			 * the offlined memory cgroups because of a
+			 * round-off error.
 			 */
-			scan = DIV64_U64_ROUND_UP(scan * fraction[file],
+			scan = mem_cgroup_online(memcg) ?
+			       div64_u64(scan * fraction[file], denominator) :
+			       DIV64_U64_ROUND_UP(scan * fraction[file],
 						  denominator);
 			break;
 		case SCAN_FILE:
@@ -2695,7 +2684,7 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc)
 	} while ((memcg = mem_cgroup_iter(target_memcg, memcg, NULL)));
 }
 
-static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
+static void shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 {
 	struct reclaim_state *reclaim_state = current->reclaim_state;
 	unsigned long nr_reclaimed, nr_scanned;
@@ -2874,8 +2863,6 @@ again:
 	 */
 	if (reclaimable)
 		pgdat->kswapd_failures = 0;
-
-	return reclaimable;
 }
 
 /*
@@ -4126,10 +4113,8 @@ module_init(kswapd_init)
  */
 int node_reclaim_mode __read_mostly;
 
-#define RECLAIM_OFF 0
-#define RECLAIM_ZONE (1<<0)	/* Run shrink_inactive_list on the zone */
-#define RECLAIM_WRITE (1<<1)	/* Writeout pages during reclaim */
-#define RECLAIM_UNMAP (1<<2)	/* Unmap pages during reclaim */
+#define RECLAIM_WRITE (1<<0)	/* Writeout pages during reclaim */
+#define RECLAIM_UNMAP (1<<1)	/* Unmap pages during reclaim */
 
 /*
  * Priority for NODE_RECLAIM. This determines the fraction of pages
diff --git a/mm/zswap.c b/mm/zswap.c
index 46a322316e52..55094e63b72d 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -32,6 +32,7 @@
 #include <linux/swapops.h>
 #include <linux/writeback.h>
 #include <linux/pagemap.h>
+#include <linux/workqueue.h>
 
 /*********************************
 * statistics
@@ -65,6 +66,11 @@ static u64 zswap_reject_kmemcache_fail;
 /* Duplicate store was encountered (rare) */
 static u64 zswap_duplicate_entry;
 
+/* Shrinker work queue */
+static struct workqueue_struct *shrink_wq;
+/* Pool limit was hit, we need to calm down */
+static bool zswap_pool_reached_full;
+
 /*********************************
 * tunables
 **********************************/
@@ -109,6 +115,11 @@ module_param_cb(zpool, &zswap_zpool_param_ops, &zswap_zpool_type, 0644);
 static unsigned int zswap_max_pool_percent = 20;
 module_param_named(max_pool_percent, zswap_max_pool_percent, uint, 0644);
 
+/* The threshold for accepting new pages after the max_pool_percent was hit */
+static unsigned int zswap_accept_thr_percent = 90; /* of max pool size */
+module_param_named(accept_threshold_percent, zswap_accept_thr_percent,
+		   uint, 0644);
+
 /* Enable/disable handling same-value filled pages (enabled by default) */
 static bool zswap_same_filled_pages_enabled = true;
 module_param_named(same_filled_pages_enabled, zswap_same_filled_pages_enabled,
@@ -123,7 +134,8 @@ struct zswap_pool {
 	struct crypto_comp * __percpu *tfm;
 	struct kref kref;
 	struct list_head list;
-	struct work_struct work;
+	struct work_struct release_work;
+	struct work_struct shrink_work;
 	struct hlist_node node;
 	char tfm_name[CRYPTO_MAX_ALG_NAME];
 };
@@ -214,6 +226,13 @@ static bool zswap_is_full(void)
 			DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
 }
 
+static bool zswap_can_accept(void)
+{
+	return totalram_pages() * zswap_accept_thr_percent / 100 *
+				zswap_max_pool_percent / 100 >
+			DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
+}
+
 static void zswap_update_total_size(void)
 {
 	struct zswap_pool *pool;
@@ -501,6 +520,16 @@ static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
 	return NULL;
 }
 
+static void shrink_worker(struct work_struct *w)
+{
+	struct zswap_pool *pool = container_of(w, typeof(*pool),
+						shrink_work);
+
+	if (zpool_shrink(pool->zpool, 1, NULL))
+		zswap_reject_reclaim_fail++;
+	zswap_pool_put(pool);
+}
+
 static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
 {
 	struct zswap_pool *pool;
@@ -551,6 +580,7 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
 	 */
 	kref_init(&pool->kref);
 	INIT_LIST_HEAD(&pool->list);
+	INIT_WORK(&pool->shrink_work, shrink_worker);
 
 	zswap_pool_debug("created", pool);
 
@@ -624,7 +654,8 @@ static int __must_check zswap_pool_get(struct zswap_pool *pool)
 
 static void __zswap_pool_release(struct work_struct *work)
 {
-	struct zswap_pool *pool = container_of(work, typeof(*pool), work);
+	struct zswap_pool *pool = container_of(work, typeof(*pool),
+						release_work);
 
 	synchronize_rcu();
 
@@ -647,8 +678,8 @@ static void __zswap_pool_empty(struct kref *kref)
 
 	list_del_rcu(&pool->list);
 
-	INIT_WORK(&pool->work, __zswap_pool_release);
-	schedule_work(&pool->work);
+	INIT_WORK(&pool->release_work, __zswap_pool_release);
+	schedule_work(&pool->release_work);
 
 	spin_unlock(&zswap_pools_lock);
 }
@@ -942,22 +973,6 @@ end:
 	return ret;
 }
 
-static int zswap_shrink(void)
-{
-	struct zswap_pool *pool;
-	int ret;
-
-	pool = zswap_pool_last_get();
-	if (!pool)
-		return -ENOENT;
-
-	ret = zpool_shrink(pool->zpool, 1, NULL);
-
-	zswap_pool_put(pool);
-
-	return ret;
-}
-
 static int zswap_is_page_same_filled(void *ptr, unsigned long *value)
 {
 	unsigned int pos;
@@ -1011,21 +1026,23 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
 
 	/* reclaim space if needed */
 	if (zswap_is_full()) {
+		struct zswap_pool *pool;
+
 		zswap_pool_limit_hit++;
-		if (zswap_shrink()) {
-			zswap_reject_reclaim_fail++;
-			ret = -ENOMEM;
-			goto reject;
-		}
+		zswap_pool_reached_full = true;
+		pool = zswap_pool_last_get();
+		if (pool)
+			queue_work(shrink_wq, &pool->shrink_work);
+		ret = -ENOMEM;
+		goto reject;
+	}
 
-		/* A second zswap_is_full() check after
-		 * zswap_shrink() to make sure it's now
-		 * under the max_pool_percent
-		 */
-		if (zswap_is_full()) {
+	if (zswap_pool_reached_full) {
+	       if (!zswap_can_accept()) {
 			ret = -ENOMEM;
 			goto reject;
-		}
+		} else
+			zswap_pool_reached_full = false;
 	}
 
 	/* allocate entry */
@@ -1332,11 +1349,18 @@ static int __init init_zswap(void)
 		zswap_enabled = false;
 	}
 
+	shrink_wq = create_workqueue("zswap-shrink");
+	if (!shrink_wq)
+		goto fallback_fail;
+
 	frontswap_register_ops(&zswap_frontswap_ops);
 	if (zswap_debugfs_init())
 		pr_warn("debugfs initialization failed\n");
 	return 0;
 
+fallback_fail:
+	if (pool)
+		zswap_pool_destroy(pool);
 hp_fail:
 	cpuhp_remove_state(CPUHP_MM_ZSWP_MEM_PREPARE);
 dstmem_fail: