38 files changed, 290 insertions, 117 deletions

diff --git a/mm/Makefile b/mm/Makefile
index 7a68d2ab5560..6c2a73a54a43 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -33,7 +33,11 @@ obj-$(CONFIG_FAILSLAB) += failslab.o
 obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
 obj-$(CONFIG_FS_XIP) += filemap_xip.o
 obj-$(CONFIG_MIGRATION) += migrate.o
-obj-$(CONFIG_SMP) += percpu.o
+ifdef CONFIG_SMP
+obj-y += percpu.o
+else
+obj-y += percpu_up.o
+endif
 obj-$(CONFIG_QUICKLIST) += quicklist.o
 obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o
 obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 0e8ca0347707..f13e067e1467 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -227,6 +227,9 @@ static struct device_attribute bdi_dev_attrs[] = {
 static __init int bdi_class_init(void)
 {
 	bdi_class = class_create(THIS_MODULE, "bdi");
+	if (IS_ERR(bdi_class))
+		return PTR_ERR(bdi_class);
+
 	bdi_class->dev_attrs = bdi_dev_attrs;
 	bdi_debug_init();
 	return 0;
diff --git a/mm/bootmem.c b/mm/bootmem.c
index 9b134460b016..58c66cc5056a 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -10,6 +10,7 @@
  */
 #include <linux/init.h>
 #include <linux/pfn.h>
+#include <linux/slab.h>
 #include <linux/bootmem.h>
 #include <linux/module.h>
 #include <linux/kmemleak.h>
@@ -303,9 +304,22 @@ unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
 unsigned long __init free_all_bootmem(void)
 {
 #ifdef CONFIG_NO_BOOTMEM
-	return free_all_memory_core_early(NODE_DATA(0)->node_id);
+	/*
+	 * We need to use MAX_NUMNODES instead of NODE_DATA(0)->node_id
+	 *  because in some case like Node0 doesnt have RAM installed
+	 *  low ram will be on Node1
+	 * Use MAX_NUMNODES will make sure all ranges in early_node_map[]
+	 *  will be used instead of only Node0 related
+	 */
+	return free_all_memory_core_early(MAX_NUMNODES);
 #else
-	return free_all_bootmem_core(NODE_DATA(0)->bdata);
+	unsigned long total_pages = 0;
+	bootmem_data_t *bdata;
+
+	list_for_each_entry(bdata, &bdata_list, list)
+		total_pages += free_all_bootmem_core(bdata);
+
+	return total_pages;
 #endif
 }
 
diff --git a/mm/bounce.c b/mm/bounce.c
index a2b76a588e34..13b6dad1eed2 100644
--- a/mm/bounce.c
+++ b/mm/bounce.c
@@ -6,6 +6,7 @@
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/swap.h>
+#include <linux/gfp.h>
 #include <linux/bio.h>
 #include <linux/pagemap.h>
 #include <linux/mempool.h>
diff --git a/mm/failslab.c b/mm/failslab.c
index bb41f98dd8b7..c5f88f240ddc 100644
--- a/mm/failslab.c
+++ b/mm/failslab.c
@@ -1,5 +1,4 @@
 #include <linux/fault-inject.h>
-#include <linux/gfp.h>
 #include <linux/slab.h>
 
 static struct {
diff --git a/mm/filemap.c b/mm/filemap.c
index 045b31c37653..140ebda9640f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -10,13 +10,13 @@
  * the NFS filesystem used to do this differently, for example)
  */
 #include <linux/module.h>
-#include <linux/slab.h>
 #include <linux/compiler.h>
 #include <linux/fs.h>
 #include <linux/uaccess.h>
 #include <linux/aio.h>
 #include <linux/capability.h>
 #include <linux/kernel_stat.h>
+#include <linux/gfp.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/mman.h>
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index 78b94f0b6d5d..83364df74a33 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -17,6 +17,7 @@
 #include <linux/sched.h>
 #include <linux/seqlock.h>
 #include <linux/mutex.h>
+#include <linux/gfp.h>
 #include <asm/tlbflush.h>
 #include <asm/io.h>
 
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 3a5aeb37c110..ffbdfc86aedf 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2,7 +2,6 @@
  * Generic hugetlb support.
  * (C) William Irwin, April 2004
  */
-#include <linux/gfp.h>
 #include <linux/list.h>
 #include <linux/init.h>
 #include <linux/module.h>
@@ -18,6 +17,7 @@
 #include <linux/mutex.h>
 #include <linux/bootmem.h>
 #include <linux/sysfs.h>
+#include <linux/slab.h>
 
 #include <asm/page.h>
 #include <asm/pgtable.h>
@@ -546,6 +546,7 @@ static void free_huge_page(struct page *page)
 
 	mapping = (struct address_space *) page_private(page);
 	set_page_private(page, 0);
+	page->mapping = NULL;
 	BUG_ON(page_count(page));
 	INIT_LIST_HEAD(&page->lru);
 
@@ -2447,8 +2448,10 @@ retry:
 			spin_lock(&inode->i_lock);
 			inode->i_blocks += blocks_per_huge_page(h);
 			spin_unlock(&inode->i_lock);
-		} else
+		} else {
 			lock_page(page);
+			page->mapping = HUGETLB_POISON;
+		}
 	}
 
 	/*
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 5b069e4f5e48..2c0d032ac898 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -72,7 +72,6 @@
 #include <linux/module.h>
 #include <linux/kthread.h>
 #include <linux/prio_tree.h>
-#include <linux/gfp.h>
 #include <linux/fs.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
diff --git a/mm/ksm.c b/mm/ksm.c
index 8cdfc2a1e8bf..956880f2ff49 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -365,7 +365,7 @@ static int break_ksm(struct vm_area_struct *vma, unsigned long addr)
 	do {
 		cond_resched();
 		page = follow_page(vma, addr, FOLL_GET);
-		if (!page)
+		if (IS_ERR_OR_NULL(page))
 			break;
 		if (PageKsm(page))
 			ret = handle_mm_fault(vma->vm_mm, vma, addr,
@@ -447,7 +447,7 @@ static struct page *get_mergeable_page(struct rmap_item *rmap_item)
 		goto out;
 
 	page = follow_page(vma, addr, FOLL_GET);
-	if (!page)
+	if (IS_ERR_OR_NULL(page))
 		goto out;
 	if (PageAnon(page)) {
 		flush_anon_page(vma, page, addr);
@@ -1086,7 +1086,7 @@ struct rmap_item *unstable_tree_search_insert(struct rmap_item *rmap_item,
 		cond_resched();
 		tree_rmap_item = rb_entry(*new, struct rmap_item, node);
 		tree_page = get_mergeable_page(tree_rmap_item);
-		if (!tree_page)
+		if (IS_ERR_OR_NULL(tree_page))
 			return NULL;
 
 		/*
@@ -1294,7 +1294,7 @@ next_mm:
 			if (ksm_test_exit(mm))
 				break;
 			*page = follow_page(vma, ksm_scan.address, FOLL_GET);
-			if (*page && PageAnon(*page)) {
+			if (!IS_ERR_OR_NULL(*page) && PageAnon(*page)) {
 				flush_anon_page(vma, *page, ksm_scan.address);
 				flush_dcache_page(*page);
 				rmap_item = get_next_rmap_item(slot,
@@ -1308,7 +1308,7 @@ next_mm:
 				up_read(&mm->mmap_sem);
 				return rmap_item;
 			}
-			if (*page)
+			if (!IS_ERR_OR_NULL(*page))
 				put_page(*page);
 			ksm_scan.address += PAGE_SIZE;
 			cond_resched();
@@ -1367,7 +1367,7 @@ next_mm:
 static void ksm_do_scan(unsigned int scan_npages)
 {
 	struct rmap_item *rmap_item;
-	struct page *page;
+	struct page *uninitialized_var(page);
 
 	while (scan_npages--) {
 		cond_resched();
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 9ed760dc7448..6c755de385f7 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1359,16 +1359,19 @@ void mem_cgroup_update_file_mapped(struct page *page, int val)
 
 	lock_page_cgroup(pc);
 	mem = pc->mem_cgroup;
-	if (!mem)
-		goto done;
-
-	if (!PageCgroupUsed(pc))
+	if (!mem || !PageCgroupUsed(pc))
 		goto done;
 
 	/*
 	 * Preemption is already disabled. We can use __this_cpu_xxx
 	 */
-	__this_cpu_add(mem->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], val);
+	if (val > 0) {
+		__this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
+		SetPageCgroupFileMapped(pc);
+	} else {
+		__this_cpu_dec(mem->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
+		ClearPageCgroupFileMapped(pc);
+	}
 
 done:
 	unlock_page_cgroup(pc);
@@ -1801,16 +1804,13 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
 static void __mem_cgroup_move_account(struct page_cgroup *pc,
 	struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge)
 {
-	struct page *page;
-
 	VM_BUG_ON(from == to);
 	VM_BUG_ON(PageLRU(pc->page));
 	VM_BUG_ON(!PageCgroupLocked(pc));
 	VM_BUG_ON(!PageCgroupUsed(pc));
 	VM_BUG_ON(pc->mem_cgroup != from);
 
-	page = pc->page;
-	if (page_mapped(page) && !PageAnon(page)) {
+	if (PageCgroupFileMapped(pc)) {
 		/* Update mapped_file data for mem_cgroup */
 		preempt_disable();
 		__this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
@@ -2429,11 +2429,11 @@ int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
 	}
 	unlock_page_cgroup(pc);
 
+	*ptr = mem;
 	if (mem) {
-		ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
+		ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, ptr, false);
 		css_put(&mem->css);
 	}
-	*ptr = mem;
 	return ret;
 }
 
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index d1f335162976..620b0b461593 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -44,6 +44,7 @@
 #include <linux/migrate.h>
 #include <linux/page-isolation.h>
 #include <linux/suspend.h>
+#include <linux/slab.h>
 #include "internal.h"
 
 int sysctl_memory_failure_early_kill __read_mostly = 0;
diff --git a/mm/memory.c b/mm/memory.c
index bc9ba5a1f5b9..833952d8b74d 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -56,6 +56,7 @@
 #include <linux/kallsyms.h>
 #include <linux/swapops.h>
 #include <linux/elf.h>
+#include <linux/gfp.h>
 
 #include <asm/io.h>
 #include <asm/pgalloc.h>
@@ -124,13 +125,12 @@ core_initcall(init_zero_pfn);
 
 #if defined(SPLIT_RSS_COUNTING)
 
-void __sync_task_rss_stat(struct task_struct *task, struct mm_struct *mm)
+static void __sync_task_rss_stat(struct task_struct *task, struct mm_struct *mm)
 {
 	int i;
 
 	for (i = 0; i < NR_MM_COUNTERS; i++) {
 		if (task->rss_stat.count[i]) {
-			BUG_ON(!mm);
 			add_mm_counter(mm, i, task->rss_stat.count[i]);
 			task->rss_stat.count[i] = 0;
 		}
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 8034abd3a135..08f40a2f3fe0 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -73,7 +73,6 @@
 #include <linux/sched.h>
 #include <linux/nodemask.h>
 #include <linux/cpuset.h>
-#include <linux/gfp.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/module.h>
diff --git a/mm/migrate.c b/mm/migrate.c
index 88000b89fc9a..d3f3f7f81075 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -32,6 +32,7 @@
 #include <linux/security.h>
 #include <linux/memcontrol.h>
 #include <linux/syscalls.h>
+#include <linux/gfp.h>
 
 #include "internal.h"
 
diff --git a/mm/mincore.c b/mm/mincore.c
index 7a3436ef39eb..f77433c20279 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -7,8 +7,8 @@
 /*
  * The mincore() system call.
  */
-#include <linux/slab.h>
 #include <linux/pagemap.h>
+#include <linux/gfp.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/syscalls.h>
diff --git a/mm/mmap.c b/mm/mmap.c
index 75557c639ad4..f90ea92f755a 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -507,11 +507,12 @@ int vma_adjust(struct vm_area_struct *vma, unsigned long start,
 	struct address_space *mapping = NULL;
 	struct prio_tree_root *root = NULL;
 	struct file *file = vma->vm_file;
-	struct anon_vma *anon_vma = NULL;
 	long adjust_next = 0;
 	int remove_next = 0;
 
 	if (next && !insert) {
+		struct vm_area_struct *exporter = NULL;
+
 		if (end >= next->vm_end) {
 			/*
 			 * vma expands, overlapping all the next, and
@@ -519,7 +520,7 @@ int vma_adjust(struct vm_area_struct *vma, unsigned long start,
 			 */
 again:			remove_next = 1 + (end > next->vm_end);
 			end = next->vm_end;
-			anon_vma = next->anon_vma;
+			exporter = next;
 			importer = vma;
 		} else if (end > next->vm_start) {
 			/*
@@ -527,7 +528,7 @@ again:			remove_next = 1 + (end > next->vm_end);
 			 * mprotect case 5 shifting the boundary up.
 			 */
 			adjust_next = (end - next->vm_start) >> PAGE_SHIFT;
-			anon_vma = next->anon_vma;
+			exporter = next;
 			importer = vma;
 		} else if (end < vma->vm_end) {
 			/*
@@ -536,28 +537,19 @@ again:			remove_next = 1 + (end > next->vm_end);
 			 * mprotect case 4 shifting the boundary down.
 			 */
 			adjust_next = - ((vma->vm_end - end) >> PAGE_SHIFT);
-			anon_vma = next->anon_vma;
+			exporter = vma;
 			importer = next;
 		}
-	}
 
-	/*
-	 * When changing only vma->vm_end, we don't really need anon_vma lock.
-	 */
-	if (vma->anon_vma && (insert || importer || start != vma->vm_start))
-		anon_vma = vma->anon_vma;
-	if (anon_vma) {
 		/*
 		 * Easily overlooked: when mprotect shifts the boundary,
 		 * make sure the expanding vma has anon_vma set if the
 		 * shrinking vma had, to cover any anon pages imported.
 		 */
-		if (importer && !importer->anon_vma) {
-			/* Block reverse map lookups until things are set up. */
-			if (anon_vma_clone(importer, vma)) {
+		if (exporter && exporter->anon_vma && !importer->anon_vma) {
+			if (anon_vma_clone(importer, exporter))
 				return -ENOMEM;
-			}
-			importer->anon_vma = anon_vma;
+			importer->anon_vma = exporter->anon_vma;
 		}
 	}
 
@@ -825,6 +817,61 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
 }
 
 /*
+ * Rough compatbility check to quickly see if it's even worth looking
+ * at sharing an anon_vma.
+ *
+ * They need to have the same vm_file, and the flags can only differ
+ * in things that mprotect may change.
+ *
+ * NOTE! The fact that we share an anon_vma doesn't _have_ to mean that
+ * we can merge the two vma's. For example, we refuse to merge a vma if
+ * there is a vm_ops->close() function, because that indicates that the
+ * driver is doing some kind of reference counting. But that doesn't
+ * really matter for the anon_vma sharing case.
+ */
+static int anon_vma_compatible(struct vm_area_struct *a, struct vm_area_struct *b)
+{
+	return a->vm_end == b->vm_start &&
+		mpol_equal(vma_policy(a), vma_policy(b)) &&
+		a->vm_file == b->vm_file &&
+		!((a->vm_flags ^ b->vm_flags) & ~(VM_READ|VM_WRITE|VM_EXEC)) &&
+		b->vm_pgoff == a->vm_pgoff + ((b->vm_start - a->vm_start) >> PAGE_SHIFT);
+}
+
+/*
+ * Do some basic sanity checking to see if we can re-use the anon_vma
+ * from 'old'. The 'a'/'b' vma's are in VM order - one of them will be
+ * the same as 'old', the other will be the new one that is trying
+ * to share the anon_vma.
+ *
+ * NOTE! This runs with mm_sem held for reading, so it is possible that
+ * the anon_vma of 'old' is concurrently in the process of being set up
+ * by another page fault trying to merge _that_. But that's ok: if it
+ * is being set up, that automatically means that it will be a singleton
+ * acceptable for merging, so we can do all of this optimistically. But
+ * we do that ACCESS_ONCE() to make sure that we never re-load the pointer.
+ *
+ * IOW: that the "list_is_singular()" test on the anon_vma_chain only
+ * matters for the 'stable anon_vma' case (ie the thing we want to avoid
+ * is to return an anon_vma that is "complex" due to having gone through
+ * a fork).
+ *
+ * We also make sure that the two vma's are compatible (adjacent,
+ * and with the same memory policies). That's all stable, even with just
+ * a read lock on the mm_sem.
+ */
+static struct anon_vma *reusable_anon_vma(struct vm_area_struct *old, struct vm_area_struct *a, struct vm_area_struct *b)
+{
+	if (anon_vma_compatible(a, b)) {
+		struct anon_vma *anon_vma = ACCESS_ONCE(old->anon_vma);
+
+		if (anon_vma && list_is_singular(&old->anon_vma_chain))
+			return anon_vma;
+	}
+	return NULL;
+}
+
+/*
  * find_mergeable_anon_vma is used by anon_vma_prepare, to check
  * neighbouring vmas for a suitable anon_vma, before it goes off
  * to allocate a new anon_vma.  It checks because a repetitive
@@ -834,28 +881,16 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
  */
 struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *vma)
 {
+	struct anon_vma *anon_vma;
 	struct vm_area_struct *near;
-	unsigned long vm_flags;
 
 	near = vma->vm_next;
 	if (!near)
 		goto try_prev;
 
-	/*
-	 * Since only mprotect tries to remerge vmas, match flags
-	 * which might be mprotected into each other later on.
-	 * Neither mlock nor madvise tries to remerge at present,
-	 * so leave their flags as obstructing a merge.
-	 */
-	vm_flags = vma->vm_flags & ~(VM_READ|VM_WRITE|VM_EXEC);
-	vm_flags |= near->vm_flags & (VM_READ|VM_WRITE|VM_EXEC);
-
-	if (near->anon_vma && vma->vm_end == near->vm_start &&
- 			mpol_equal(vma_policy(vma), vma_policy(near)) &&
-			can_vma_merge_before(near, vm_flags,
-				NULL, vma->vm_file, vma->vm_pgoff +
-				((vma->vm_end - vma->vm_start) >> PAGE_SHIFT)))
-		return near->anon_vma;
+	anon_vma = reusable_anon_vma(near, vma, near);
+	if (anon_vma)
+		return anon_vma;
 try_prev:
 	/*
 	 * It is potentially slow to have to call find_vma_prev here.
@@ -868,14 +903,9 @@ try_prev:
 	if (!near)
 		goto none;
 
-	vm_flags = vma->vm_flags & ~(VM_READ|VM_WRITE|VM_EXEC);
-	vm_flags |= near->vm_flags & (VM_READ|VM_WRITE|VM_EXEC);
-
-	if (near->anon_vma && near->vm_end == vma->vm_start &&
-  			mpol_equal(vma_policy(near), vma_policy(vma)) &&
-			can_vma_merge_after(near, vm_flags,
-				NULL, vma->vm_file, vma->vm_pgoff))
-		return near->anon_vma;
+	anon_vma = reusable_anon_vma(near, near, vma);
+	if (anon_vma)
+		return anon_vma;
 none:
 	/*
 	 * There's no absolute need to look only at touching neighbours:
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index 7e33f2cb3c77..438951d366f2 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -16,6 +16,7 @@
 #include <linux/err.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
+#include <linux/slab.h>
 
 /*
  * This function can't run concurrently against mmu_notifier_register
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 8bc969d8112d..2d1bf7cf8851 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -10,7 +10,6 @@
 
 #include <linux/mm.h>
 #include <linux/hugetlb.h>
-#include <linux/slab.h>
 #include <linux/shm.h>
 #include <linux/mman.h>
 #include <linux/fs.h>
diff --git a/mm/mremap.c b/mm/mremap.c
index e9c75efce609..cde56ee51ef7 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -9,7 +9,6 @@
 
 #include <linux/mm.h>
 #include <linux/hugetlb.h>
-#include <linux/slab.h>
 #include <linux/shm.h>
 #include <linux/ksm.h>
 #include <linux/mman.h>
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 9b223af6a147..b68e802a7a7d 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -18,6 +18,7 @@
 #include <linux/oom.h>
 #include <linux/mm.h>
 #include <linux/err.h>
+#include <linux/gfp.h>
 #include <linux/sched.h>
 #include <linux/swap.h>
 #include <linux/timex.h>
diff --git a/mm/page_io.c b/mm/page_io.c
index a19af956ee1b..31a3b962230a 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -12,6 +12,7 @@
 
 #include <linux/mm.h>
 #include <linux/kernel_stat.h>
+#include <linux/gfp.h>
 #include <linux/pagemap.h>
 #include <linux/swap.h>
 #include <linux/bio.h>
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index 7b47a57b6646..8b1a2ce21ee5 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -80,6 +80,37 @@ static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 	return err;
 }
 
+#ifdef CONFIG_HUGETLB_PAGE
+static unsigned long hugetlb_entry_end(struct hstate *h, unsigned long addr,
+				       unsigned long end)
+{
+	unsigned long boundary = (addr & huge_page_mask(h)) + huge_page_size(h);
+	return boundary < end ? boundary : end;
+}
+
+static int walk_hugetlb_range(struct vm_area_struct *vma,
+			      unsigned long addr, unsigned long end,
+			      struct mm_walk *walk)
+{
+	struct hstate *h = hstate_vma(vma);
+	unsigned long next;
+	unsigned long hmask = huge_page_mask(h);
+	pte_t *pte;
+	int err = 0;
+
+	do {
+		next = hugetlb_entry_end(h, addr, end);
+		pte = huge_pte_offset(walk->mm, addr & hmask);
+		if (pte && walk->hugetlb_entry)
+			err = walk->hugetlb_entry(pte, hmask, addr, next, walk);
+		if (err)
+			return err;
+	} while (addr = next, addr != end);
+
+	return 0;
+}
+#endif
+
 /**
  * walk_page_range - walk a memory map's page tables with a callback
  * @mm: memory map to walk
@@ -128,20 +159,16 @@ int walk_page_range(unsigned long addr, unsigned long end,
 		vma = find_vma(walk->mm, addr);
 #ifdef CONFIG_HUGETLB_PAGE
 		if (vma && is_vm_hugetlb_page(vma)) {
-			pte_t *pte;
-			struct hstate *hs;
-
 			if (vma->vm_end < next)
 				next = vma->vm_end;
-			hs = hstate_vma(vma);
-			pte = huge_pte_offset(walk->mm,
-					      addr & huge_page_mask(hs));
-			if (pte && !huge_pte_none(huge_ptep_get(pte))
-			    && walk->hugetlb_entry)
-				err = walk->hugetlb_entry(pte, addr,
-							  next, walk);
+			/*
+			 * Hugepage is very tightly coupled with vma, so
+			 * walk through hugetlb entries within a given vma.
+			 */
+			err = walk_hugetlb_range(vma, addr, next, walk);
 			if (err)
 				break;
+			pgd = pgd_offset(walk->mm, next);
 			continue;
 		}
 #endif
diff --git a/mm/percpu.c b/mm/percpu.c
index 768419d44ad7..6e09741ddc62 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1304,6 +1304,32 @@ void free_percpu(void __percpu *ptr)
 EXPORT_SYMBOL_GPL(free_percpu);
 
 /**
+ * is_kernel_percpu_address - test whether address is from static percpu area
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to in-kernel static percpu area.  Module
+ * static percpu areas are not considered.  For those, use
+ * is_module_percpu_address().
+ *
+ * RETURNS:
+ * %true if @addr is from in-kernel static percpu area, %false otherwise.
+ */
+bool is_kernel_percpu_address(unsigned long addr)
+{
+	const size_t static_size = __per_cpu_end - __per_cpu_start;
+	void __percpu *base = __addr_to_pcpu_ptr(pcpu_base_addr);
+	unsigned int cpu;
+
+	for_each_possible_cpu(cpu) {
+		void *start = per_cpu_ptr(base, cpu);
+
+		if ((void *)addr >= start && (void *)addr < start + static_size)
+			return true;
+        }
+	return false;
+}
+
+/**
  * per_cpu_ptr_to_phys - convert translated percpu address to physical address
  * @addr: the address to be converted to physical address
  *
diff --git a/mm/percpu_up.c b/mm/percpu_up.c
new file mode 100644
index 000000000000..c4351c7f57d2
--- /dev/null
+++ b/mm/percpu_up.c
@@ -0,0 +1,30 @@
+/*
+ * mm/percpu_up.c - dummy percpu memory allocator implementation for UP
+ */
+
+#include <linux/module.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+
+void __percpu *__alloc_percpu(size_t size, size_t align)
+{
+	/*
+	 * Can't easily make larger alignment work with kmalloc.  WARN
+	 * on it.  Larger alignment should only be used for module
+	 * percpu sections on SMP for which this path isn't used.
+	 */
+	WARN_ON_ONCE(align > SMP_CACHE_BYTES);
+	return kzalloc(size, GFP_KERNEL);
+}
+EXPORT_SYMBOL_GPL(__alloc_percpu);
+
+void free_percpu(void __percpu *p)
+{
+	kfree(p);
+}
+EXPORT_SYMBOL_GPL(free_percpu);
+
+phys_addr_t per_cpu_ptr_to_phys(void *addr)
+{
+	return __pa(addr);
+}
diff --git a/mm/quicklist.c b/mm/quicklist.c
index 6633965bb27b..2876349339a7 100644
--- a/mm/quicklist.c
+++ b/mm/quicklist.c
@@ -14,6 +14,7 @@
  */
 #include <linux/kernel.h>
 
+#include <linux/gfp.h>
 #include <linux/mm.h>
 #include <linux/mmzone.h>
 #include <linux/module.h>
diff --git a/mm/readahead.c b/mm/readahead.c
index 337b20e946f6..dfa9a1a03a11 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -9,6 +9,7 @@
 
 #include <linux/kernel.h>
 #include <linux/fs.h>
+#include <linux/gfp.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/blkdev.h>
@@ -502,7 +503,7 @@ void page_cache_sync_readahead(struct address_space *mapping,
 		return;
 
 	/* be dumb */
-	if (filp->f_mode & FMODE_RANDOM) {
+	if (filp && (filp->f_mode & FMODE_RANDOM)) {
 		force_page_cache_readahead(mapping, filp, offset, req_size);
 		return;
 	}
diff --git a/mm/rmap.c b/mm/rmap.c
index fcd593c9c997..07fc94758799 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -133,8 +133,8 @@ int anon_vma_prepare(struct vm_area_struct *vma)
 				goto out_enomem_free_avc;
 			allocated = anon_vma;
 		}
-		spin_lock(&anon_vma->lock);
 
+		spin_lock(&anon_vma->lock);
 		/* page_table_lock to protect against threads */
 		spin_lock(&mm->page_table_lock);
 		if (likely(!vma->anon_vma)) {
@@ -144,14 +144,15 @@ int anon_vma_prepare(struct vm_area_struct *vma)
 			list_add(&avc->same_vma, &vma->anon_vma_chain);
 			list_add(&avc->same_anon_vma, &anon_vma->head);
 			allocated = NULL;
+			avc = NULL;
 		}
 		spin_unlock(&mm->page_table_lock);
-
 		spin_unlock(&anon_vma->lock);
-		if (unlikely(allocated)) {
+
+		if (unlikely(allocated))
 			anon_vma_free(allocated);
+		if (unlikely(avc))
 			anon_vma_chain_free(avc);
-		}
 	}
 	return 0;
 
@@ -182,7 +183,7 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
 {
 	struct anon_vma_chain *avc, *pavc;
 
-	list_for_each_entry(pavc, &src->anon_vma_chain, same_vma) {
+	list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
 		avc = anon_vma_chain_alloc();
 		if (!avc)
 			goto enomem_failure;
@@ -232,6 +233,7 @@ int anon_vma_fork(struct vm_area_struct *vma, struct vm_area_struct *pvma)
  out_error_free_anon_vma:
 	anon_vma_free(anon_vma);
  out_error:
+	unlink_anon_vmas(vma);
 	return -ENOMEM;
 }
 
@@ -729,13 +731,29 @@ void page_move_anon_rmap(struct page *page,
  * @page:	the page to add the mapping to
  * @vma:	the vm area in which the mapping is added
  * @address:	the user virtual address mapped
+ * @exclusive:	the page is exclusively owned by the current process
  */
 static void __page_set_anon_rmap(struct page *page,
-	struct vm_area_struct *vma, unsigned long address)
+	struct vm_area_struct *vma, unsigned long address, int exclusive)
 {
 	struct anon_vma *anon_vma = vma->anon_vma;
 
 	BUG_ON(!anon_vma);
+
+	/*
+	 * If the page isn't exclusively mapped into this vma,
+	 * we must use the _oldest_ possible anon_vma for the
+	 * page mapping!
+	 *
+	 * So take the last AVC chain entry in the vma, which is
+	 * the deepest ancestor, and use the anon_vma from that.
+	 */
+	if (!exclusive) {
+		struct anon_vma_chain *avc;
+		avc = list_entry(vma->anon_vma_chain.prev, struct anon_vma_chain, same_vma);
+		anon_vma = avc->anon_vma;
+	}
+
 	anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON;
 	page->mapping = (struct address_space *) anon_vma;
 	page->index = linear_page_index(vma, address);
@@ -790,7 +808,7 @@ void page_add_anon_rmap(struct page *page,
 	VM_BUG_ON(!PageLocked(page));
 	VM_BUG_ON(address < vma->vm_start || address >= vma->vm_end);
 	if (first)
-		__page_set_anon_rmap(page, vma, address);
+		__page_set_anon_rmap(page, vma, address, 0);
 	else
 		__page_check_anon_rmap(page, vma, address);
 }
@@ -812,7 +830,7 @@ void page_add_new_anon_rmap(struct page *page,
 	SetPageSwapBacked(page);
 	atomic_set(&page->_mapcount, 0); /* increment count (starts at -1) */
 	__inc_zone_page_state(page, NR_ANON_PAGES);
-	__page_set_anon_rmap(page, vma, address);
+	__page_set_anon_rmap(page, vma, address, 1);
 	if (page_evictable(page, vma))
 		lru_cache_add_lru(page, LRU_ACTIVE_ANON);
 	else
diff --git a/mm/slab.c b/mm/slab.c
index a9f325b28bed..bac0f4fcc216 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3602,21 +3602,10 @@ EXPORT_SYMBOL(kmem_cache_alloc_notrace);
  */
 int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr)
 {
-	unsigned long addr = (unsigned long)ptr;
-	unsigned long min_addr = PAGE_OFFSET;
-	unsigned long align_mask = BYTES_PER_WORD - 1;
 	unsigned long size = cachep->buffer_size;
 	struct page *page;
 
-	if (unlikely(addr < min_addr))
-		goto out;
-	if (unlikely(addr > (unsigned long)high_memory - size))
-		goto out;
-	if (unlikely(addr & align_mask))
-		goto out;
-	if (unlikely(!kern_addr_valid(addr)))
-		goto out;
-	if (unlikely(!kern_addr_valid(addr + size - 1)))
+	if (unlikely(!kern_ptr_validate(ptr, size)))
 		goto out;
 	page = virt_to_page(ptr);
 	if (unlikely(!PageSlab(page)))
diff --git a/mm/slub.c b/mm/slub.c
index b364844a1068..7d6c8b1ccf63 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2386,6 +2386,9 @@ int kmem_ptr_validate(struct kmem_cache *s, const void *object)
 {
 	struct page *page;
 
+	if (!kern_ptr_validate(object, s->size))
+		return 0;
+
 	page = get_object_page(object);
 
 	if (!page || s != page->slab)
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 392b9bb5bc01..aa33fd67fa41 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -22,6 +22,7 @@
 #include <linux/bootmem.h>
 #include <linux/highmem.h>
 #include <linux/module.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/vmalloc.h>
 #include <linux/sched.h>
diff --git a/mm/sparse.c b/mm/sparse.c
index 22896d589133..dc0cc4d43ff3 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -2,6 +2,7 @@
  * sparse memory mappings.
  */
 #include <linux/mm.h>
+#include <linux/slab.h>
 #include <linux/mmzone.h>
 #include <linux/bootmem.h>
 #include <linux/highmem.h>
diff --git a/mm/swap.c b/mm/swap.c
index 9036b89813ac..7cd60bf0a972 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -30,6 +30,7 @@
 #include <linux/notifier.h>
 #include <linux/backing-dev.h>
 #include <linux/memcontrol.h>
+#include <linux/gfp.h>
 
 #include "internal.h"
 
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 6d1daeb1cb4a..e10f5833167f 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -8,6 +8,7 @@
  */
 #include <linux/module.h>
 #include <linux/mm.h>
+#include <linux/gfp.h>
 #include <linux/kernel_stat.h>
 #include <linux/swap.h>
 #include <linux/swapops.h>
diff --git a/mm/truncate.c b/mm/truncate.c
index e87e37244829..f42675a3615d 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -9,6 +9,7 @@
 
 #include <linux/kernel.h>
 #include <linux/backing-dev.h>
+#include <linux/gfp.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/module.h>
diff --git a/mm/util.c b/mm/util.c
index 834db7be240f..f5712e8964be 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -186,6 +186,27 @@ void kzfree(const void *p)
 }
 EXPORT_SYMBOL(kzfree);
 
+int kern_ptr_validate(const void *ptr, unsigned long size)
+{
+	unsigned long addr = (unsigned long)ptr;
+	unsigned long min_addr = PAGE_OFFSET;
+	unsigned long align_mask = sizeof(void *) - 1;
+
+	if (unlikely(addr < min_addr))
+		goto out;
+	if (unlikely(addr > (unsigned long)high_memory - size))
+		goto out;
+	if (unlikely(addr & align_mask))
+		goto out;
+	if (unlikely(!kern_addr_valid(addr)))
+		goto out;
+	if (unlikely(!kern_addr_valid(addr + size - 1)))
+		goto out;
+	return 1;
+out:
+	return 0;
+}
+
 /*
  * strndup_user - duplicate an existing string from user space
  * @s: The string to duplicate
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 79c809895fba..3ff3311447f5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -13,7 +13,7 @@
 
 #include <linux/mm.h>
 #include <linux/module.h>
-#include <linux/slab.h>
+#include <linux/gfp.h>
 #include <linux/kernel_stat.h>
 #include <linux/swap.h>
 #include <linux/pagemap.h>
@@ -1535,13 +1535,6 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
 	unsigned long ap, fp;
 	struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
 
-	/* If we have no swap space, do not bother scanning anon pages. */
-	if (!sc->may_swap || (nr_swap_pages <= 0)) {
-		percent[0] = 0;
-		percent[1] = 100;
-		return;
-	}
-
 	anon  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
 		zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON);
 	file  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_FILE) +
@@ -1639,20 +1632,22 @@ static void shrink_zone(int priority, struct zone *zone,
 	unsigned long nr_reclaimed = sc->nr_reclaimed;
 	unsigned long nr_to_reclaim = sc->nr_to_reclaim;
 	struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
+	int noswap = 0;
 
-	get_scan_ratio(zone, sc, percent);
+	/* If we have no swap space, do not bother scanning anon pages. */
+	if (!sc->may_swap || (nr_swap_pages <= 0)) {
+		noswap = 1;
+		percent[0] = 0;
+		percent[1] = 100;
+	} else
+		get_scan_ratio(zone, sc, percent);
 
 	for_each_evictable_lru(l) {
 		int file = is_file_lru(l);
 		unsigned long scan;
 
-		if (percent[file] == 0) {
-			nr[l] = 0;
-			continue;
-		}
-
 		scan = zone_nr_lru_pages(zone, sc, l);
-		if (priority) {
+		if (priority || noswap) {
 			scan >>= priority;
 			scan = (scan * percent[file]) / 100;
 		}
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 7f760cbc73f3..fa12ea3051fb 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -12,6 +12,7 @@
 #include <linux/mm.h>
 #include <linux/err.h>
 #include <linux/module.h>
+#include <linux/slab.h>
 #include <linux/cpu.h>
 #include <linux/vmstat.h>
 #include <linux/sched.h>