Merge branch 'master' into for-next

41 files changed, 357 insertions, 170 deletions

diff --git a/mm/Makefile b/mm/Makefile
index 7a68d2ab556..6c2a73a54a4 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 0e8ca034770..f13e067e146 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 d7c791ef003..58c66cc5056 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>
@@ -180,19 +181,12 @@ static void __init __free_pages_memory(unsigned long start, unsigned long end)
 	end_aligned = end & ~(BITS_PER_LONG - 1);
 
 	if (end_aligned <= start_aligned) {
-#if 1
-		printk(KERN_DEBUG " %lx - %lx\n", start, end);
-#endif
 		for (i = start; i < end; i++)
 			__free_pages_bootmem(pfn_to_page(i), 0);
 
 		return;
 	}
 
-#if 1
-	printk(KERN_DEBUG " %lx %lx - %lx %lx\n",
-		 start, start_aligned, end_aligned, end);
-#endif
 	for (i = start; i < start_aligned; i++)
 		__free_pages_bootmem(pfn_to_page(i), 0);
 
@@ -310,9 +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
 }
 
@@ -428,9 +435,6 @@ void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
 {
 #ifdef CONFIG_NO_BOOTMEM
 	free_early(physaddr, physaddr + size);
-#if 0
-	printk(KERN_DEBUG "free %lx %lx\n", physaddr, size);
-#endif
 #else
 	unsigned long start, end;
 
@@ -456,9 +460,6 @@ void __init free_bootmem(unsigned long addr, unsigned long size)
 {
 #ifdef CONFIG_NO_BOOTMEM
 	free_early(addr, addr + size);
-#if 0
-	printk(KERN_DEBUG "free %lx %lx\n", addr, size);
-#endif
 #else
 	unsigned long start, end;
 
diff --git a/mm/bounce.c b/mm/bounce.c
index a2b76a588e3..13b6dad1eed 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 bb41f98dd8b..c5f88f240dd 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 045b31c3765..140ebda9640 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 78b94f0b6d5..83364df74a3 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 3a5aeb37c11..6034dc9e979 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>
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 5b069e4f5e4..2c0d032ac89 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 a93f1b7f508..8cdfc2a1e8b 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -751,7 +751,7 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
 		 * page
 		 */
 		if (page_mapcount(page) + 1 + swapped != page_count(page)) {
-			set_pte_at_notify(mm, addr, ptep, entry);
+			set_pte_at(mm, addr, ptep, entry);
 			goto out_unlock;
 		}
 		entry = pte_wrprotect(entry);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6e8533e2861..f0ff5a7af31 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]);
@@ -3691,8 +3691,10 @@ static struct mem_cgroup *mem_cgroup_alloc(void)
 	else
 		mem = vmalloc(size);
 
-	if (mem)
-		memset(mem, 0, size);
+	if (!mem)
+		return NULL;
+
+	memset(mem, 0, size);
 	mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu);
 	if (!mem->stat) {
 		if (size < PAGE_SIZE)
@@ -3946,28 +3948,6 @@ one_by_one:
 	}
 	return ret;
 }
-#else	/* !CONFIG_MMU */
-static int mem_cgroup_can_attach(struct cgroup_subsys *ss,
-				struct cgroup *cgroup,
-				struct task_struct *p,
-				bool threadgroup)
-{
-	return 0;
-}
-static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss,
-				struct cgroup *cgroup,
-				struct task_struct *p,
-				bool threadgroup)
-{
-}
-static void mem_cgroup_move_task(struct cgroup_subsys *ss,
-				struct cgroup *cont,
-				struct cgroup *old_cont,
-				struct task_struct *p,
-				bool threadgroup)
-{
-}
-#endif
 
 /**
  * is_target_pte_for_mc - check a pte whether it is valid for move charge
@@ -4330,6 +4310,28 @@ static void mem_cgroup_move_task(struct cgroup_subsys *ss,
 	}
 	mem_cgroup_clear_mc();
 }
+#else	/* !CONFIG_MMU */
+static int mem_cgroup_can_attach(struct cgroup_subsys *ss,
+				struct cgroup *cgroup,
+				struct task_struct *p,
+				bool threadgroup)
+{
+	return 0;
+}
+static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss,
+				struct cgroup *cgroup,
+				struct task_struct *p,
+				bool threadgroup)
+{
+}
+static void mem_cgroup_move_task(struct cgroup_subsys *ss,
+				struct cgroup *cont,
+				struct cgroup *old_cont,
+				struct task_struct *p,
+				bool threadgroup)
+{
+}
+#endif
 
 struct cgroup_subsys mem_cgroup_subsys = {
 	.name = "memory",
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index d1f33516297..620b0b46159 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 5b7f2002e54..833952d8b74 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>
@@ -124,7 +125,7 @@ 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;
 
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index bda230e52ac..08f40a2f3fe 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>
@@ -806,9 +805,13 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
 
 	err = 0;
 	if (nmask) {
-		task_lock(current);
-		get_policy_nodemask(pol, nmask);
-		task_unlock(current);
+		if (mpol_store_user_nodemask(pol)) {
+			*nmask = pol->w.user_nodemask;
+		} else {
+			task_lock(current);
+			get_policy_nodemask(pol, nmask);
+			task_unlock(current);
+		}
 	}
 
  out:
@@ -1756,10 +1759,12 @@ struct mempolicy *__mpol_dup(struct mempolicy *old)
 
 	if (!new)
 		return ERR_PTR(-ENOMEM);
+	rcu_read_lock();
 	if (current_cpuset_is_being_rebound()) {
 		nodemask_t mems = cpuset_mems_allowed(current);
 		mpol_rebind_policy(old, &mems);
 	}
+	rcu_read_unlock();
 	*new = *old;
 	atomic_set(&new->refcnt, 1);
 	return new;
@@ -2193,8 +2198,8 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 			char *rest = nodelist;
 			while (isdigit(*rest))
 				rest++;
-			if (!*rest)
-				err = 0;
+			if (*rest)
+				goto out;
 		}
 		break;
 	case MPOL_INTERLEAVE:
@@ -2203,7 +2208,6 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 		 */
 		if (!nodelist)
 			nodes = node_states[N_HIGH_MEMORY];
-		err = 0;
 		break;
 	case MPOL_LOCAL:
 		/*
@@ -2213,11 +2217,19 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 			goto out;
 		mode = MPOL_PREFERRED;
 		break;
-
-	/*
-	 * case MPOL_BIND:    mpol_new() enforces non-empty nodemask.
-	 * case MPOL_DEFAULT: mpol_new() enforces empty nodemask, ignores flags.
-	 */
+	case MPOL_DEFAULT:
+		/*
+		 * Insist on a empty nodelist
+		 */
+		if (!nodelist)
+			err = 0;
+		goto out;
+	case MPOL_BIND:
+		/*
+		 * Insist on a nodelist
+		 */
+		if (!nodelist)
+			goto out;
 	}
 
 	mode_flags = 0;
@@ -2231,13 +2243,14 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 		else if (!strcmp(flags, "relative"))
 			mode_flags |= MPOL_F_RELATIVE_NODES;
 		else
-			err = 1;
+			goto out;
 	}
 
 	new = mpol_new(mode, mode_flags, &nodes);
 	if (IS_ERR(new))
-		err = 1;
-	else {
+		goto out;
+
+	{
 		int ret;
 		NODEMASK_SCRATCH(scratch);
 		if (scratch) {
@@ -2248,13 +2261,15 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 			ret = -ENOMEM;
 		NODEMASK_SCRATCH_FREE(scratch);
 		if (ret) {
-			err = 1;
 			mpol_put(new);
-		} else if (no_context) {
-			/* save for contextualization */
-			new->w.user_nodemask = nodes;
+			goto out;
 		}
 	}
+	err = 0;
+	if (no_context) {
+		/* save for contextualization */
+		new->w.user_nodemask = nodes;
+	}
 
 out:
 	/* Restore string for error message */
diff --git a/mm/migrate.c b/mm/migrate.c
index 88000b89fc9..d3f3f7f8107 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 7a3436ef39e..f77433c2027 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 75557c639ad..f90ea92f755 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_context.c b/mm/mmu_context.c
index 0777654147c..9e82e937000 100644
--- a/mm/mmu_context.c
+++ b/mm/mmu_context.c
@@ -53,6 +53,7 @@ void unuse_mm(struct mm_struct *mm)
 	struct task_struct *tsk = current;
 
 	task_lock(tsk);
+	sync_mm_rss(tsk, mm);
 	tsk->mm = NULL;
 	/* active_mm is still 'mm' */
 	enter_lazy_tlb(mm, tsk);
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index 7e33f2cb3c7..438951d366f 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 8bc969d8112..2d1bf7cf885 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 e9c75efce60..cde56ee51ef 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/nommu.c b/mm/nommu.c
index 605ace8982a..63fa17d121f 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -146,7 +146,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 			(VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
 
 	for (i = 0; i < nr_pages; i++) {
-		vma = find_extend_vma(mm, start);
+		vma = find_vma(mm, start);
 		if (!vma)
 			goto finish_or_fault;
 
@@ -162,7 +162,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 		}
 		if (vmas)
 			vmas[i] = vma;
-		start += PAGE_SIZE;
+		start = (start + PAGE_SIZE) & PAGE_MASK;
 	}
 
 	return i;
@@ -764,7 +764,7 @@ EXPORT_SYMBOL(find_vma);
  */
 struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
 {
-	return find_vma(mm, addr & PAGE_MASK);
+	return find_vma(mm, addr);
 }
 
 /*
@@ -1040,10 +1040,9 @@ static int do_mmap_shared_file(struct vm_area_struct *vma)
 	if (ret != -ENOSYS)
 		return ret;