Merge branch 'linus' into sched/core, to pick up fixes

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

4 files changed, 51 insertions, 24 deletions

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 945fd1ca49b5..df4ebdb2b10a 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -652,7 +652,6 @@ static void __collapse_huge_page_copy(pte_t *pte, struct page *page,
 			spin_unlock(ptl);
 			free_page_and_swap_cache(src_page);
 		}
-		cond_resched();
 	}
 }
 
diff --git a/mm/mmap.c b/mm/mmap.c
index 8e07976d5e47..a5e3dcd75e79 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1817,7 +1817,8 @@ check_current:
 		/* Check if current node has a suitable gap */
 		if (gap_start > high_limit)
 			return -ENOMEM;
-		if (gap_end >= low_limit && gap_end - gap_start >= length)
+		if (gap_end >= low_limit &&
+		    gap_end > gap_start && gap_end - gap_start >= length)
 			goto found;
 
 		/* Visit right subtree if it looks promising */
@@ -1920,7 +1921,8 @@ check_current:
 		gap_end = vm_start_gap(vma);
 		if (gap_end < low_limit)
 			return -ENOMEM;
-		if (gap_start <= high_limit && gap_end - gap_start >= length)
+		if (gap_start <= high_limit &&
+		    gap_end > gap_start && gap_end - gap_start >= length)
 			goto found;
 
 		/* Visit left subtree if it looks promising */
@@ -2228,16 +2230,19 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
 	if (!(vma->vm_flags & VM_GROWSUP))
 		return -EFAULT;
 
-	/* Guard against wrapping around to address 0. */
+	/* Guard against exceeding limits of the address space. */
 	address &= PAGE_MASK;
-	address += PAGE_SIZE;
-	if (!address)
+	if (address >= TASK_SIZE)
 		return -ENOMEM;
+	address += PAGE_SIZE;
 
 	/* Enforce stack_guard_gap */
 	gap_addr = address + stack_guard_gap;
-	if (gap_addr < address)
-		return -ENOMEM;
+
+	/* Guard against overflow */
+	if (gap_addr < address || gap_addr > TASK_SIZE)
+		gap_addr = TASK_SIZE;
+
 	next = vma->vm_next;
 	if (next && next->vm_start < gap_addr) {
 		if (!(next->vm_flags & VM_GROWSUP))
diff --git a/mm/slub.c b/mm/slub.c
index 7449593fca72..8addc535bcdc 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -5625,6 +5625,28 @@ static char *create_unique_id(struct kmem_cache *s)
 	return name;
 }
 
+static void sysfs_slab_remove_workfn(struct work_struct *work)
+{
+	struct kmem_cache *s =
+		container_of(work, struct kmem_cache, kobj_remove_work);
+
+	if (!s->kobj.state_in_sysfs)
+		/*
+		 * For a memcg cache, this may be called during
+		 * deactivation and again on shutdown.  Remove only once.
+		 * A cache is never shut down before deactivation is
+		 * complete, so no need to worry about synchronization.
+		 */
+		return;
+
+#ifdef CONFIG_MEMCG
+	kset_unregister(s->memcg_kset);
+#endif
+	kobject_uevent(&s->kobj, KOBJ_REMOVE);
+	kobject_del(&s->kobj);
+	kobject_put(&s->kobj);
+}
+
 static int sysfs_slab_add(struct kmem_cache *s)
 {
 	int err;
@@ -5632,6 +5654,8 @@ static int sysfs_slab_add(struct kmem_cache *s)
 	struct kset *kset = cache_kset(s);
 	int unmergeable = slab_unmergeable(s);
 
+	INIT_WORK(&s->kobj_remove_work, sysfs_slab_remove_workfn);
+
 	if (!kset) {
 		kobject_init(&s->kobj, &slab_ktype);
 		return 0;
@@ -5695,20 +5719,8 @@ static void sysfs_slab_remove(struct kmem_cache *s)
 		 */
 		return;
 
-	if (!s->kobj.state_in_sysfs)
-		/*
-		 * For a memcg cache, this may be called during
-		 * deactivation and again on shutdown.  Remove only once.
-		 * A cache is never shut down before deactivation is
-		 * complete, so no need to worry about synchronization.
-		 */
-		return;
-
-#ifdef CONFIG_MEMCG
-	kset_unregister(s->memcg_kset);
-#endif
-	kobject_uevent(&s->kobj, KOBJ_REMOVE);
-	kobject_del(&s->kobj);
+	kobject_get(&s->kobj);
+	schedule_work(&s->kobj_remove_work);
 }
 
 void sysfs_slab_release(struct kmem_cache *s)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 34a1c3e46ed7..ecc97f74ab18 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -287,10 +287,21 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
 	if (p4d_none(*p4d))
 		return NULL;
 	pud = pud_offset(p4d, addr);
-	if (pud_none(*pud))
+
+	/*
+	 * Don't dereference bad PUD or PMD (below) entries. This will also
+	 * identify huge mappings, which we may encounter on architectures
+	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
+	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
+	 * not [unambiguously] associated with a struct page, so there is
+	 * no correct value to return for them.
+	 */
+	WARN_ON_ONCE(pud_bad(*pud));
+	if (pud_none(*pud) || pud_bad(*pud))
 		return NULL;
 	pmd = pmd_offset(pud, addr);
-	if (pmd_none(*pmd))
+	WARN_ON_ONCE(pmd_bad(*pmd));
+	if (pmd_none(*pmd) || pmd_bad(*pmd))
 		return NULL;
 
 	ptep = pte_offset_map(pmd, addr);