Merge tag 'v3.3-rc7' into x86/mce

Merge reason: Update from an ancient -rc1 base to an almost-final stable kernel.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

22 files changed, 171 insertions, 130 deletions

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 7ba8fea..dd8e2aa 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -318,7 +318,7 @@ static void wakeup_timer_fn(unsigned long data)
 	if (bdi->wb.task) {
 		trace_writeback_wake_thread(bdi);
 		wake_up_process(bdi->wb.task);
-	} else {
+	} else if (bdi->dev) {
 		/*
 		 * When bdi tasks are inactive for long time, they are killed.
 		 * In this case we have to wake-up the forker thread which
@@ -584,6 +584,8 @@ EXPORT_SYMBOL(bdi_register_dev);
  */
 static void bdi_wb_shutdown(struct backing_dev_info *bdi)
 {
+	struct task_struct *task;
+
 	if (!bdi_cap_writeback_dirty(bdi))
 		return;
 
@@ -602,8 +604,13 @@ static void bdi_wb_shutdown(struct backing_dev_info *bdi)
 	 * Finally, kill the kernel thread. We don't need to be RCU
 	 * safe anymore, since the bdi is gone from visibility.
 	 */
-	if (bdi->wb.task)
-		kthread_stop(bdi->wb.task);
+	spin_lock_bh(&bdi->wb_lock);
+	task = bdi->wb.task;
+	bdi->wb.task = NULL;
+	spin_unlock_bh(&bdi->wb_lock);
+
+	if (task)
+		kthread_stop(task);
 }
 
 /*
@@ -623,7 +630,9 @@ static void bdi_prune_sb(struct backing_dev_info *bdi)
 
 void bdi_unregister(struct backing_dev_info *bdi)
 {
-	if (bdi->dev) {
+	struct device *dev = bdi->dev;
+
+	if (dev) {
 		bdi_set_min_ratio(bdi, 0);
 		trace_writeback_bdi_unregister(bdi);
 		bdi_prune_sb(bdi);
@@ -632,8 +641,12 @@ void bdi_unregister(struct backing_dev_info *bdi)
 		if (!bdi_cap_flush_forker(bdi))
 			bdi_wb_shutdown(bdi);
 		bdi_debug_unregister(bdi);
-		device_unregister(bdi->dev);
+
+		spin_lock_bh(&bdi->wb_lock);
 		bdi->dev = NULL;
+		spin_unlock_bh(&bdi->wb_lock);
+
+		device_unregister(dev);
 	}
 }
 EXPORT_SYMBOL(bdi_unregister);
diff --git a/mm/compaction.c b/mm/compaction.c
index 71a58f6..d9ebebe 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -313,12 +313,34 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
 		} else if (!locked)
 			spin_lock_irq(&zone->lru_lock);
 
+		/*
+		 * migrate_pfn does not necessarily start aligned to a
+		 * pageblock. Ensure that pfn_valid is called when moving
+		 * into a new MAX_ORDER_NR_PAGES range in case of large
+		 * memory holes within the zone
+		 */
+		if ((low_pfn & (MAX_ORDER_NR_PAGES - 1)) == 0) {
+			if (!pfn_valid(low_pfn)) {
+				low_pfn += MAX_ORDER_NR_PAGES - 1;
+				continue;
+			}
+		}
+
 		if (!pfn_valid_within(low_pfn))
 			continue;
 		nr_scanned++;
 
-		/* Get the page and skip if free */
+		/*
+		 * Get the page and ensure the page is within the same zone.
+		 * See the comment in isolate_freepages about overlapping
+		 * nodes. It is deliberate that the new zone lock is not taken
+		 * as memory compaction should not move pages between nodes.
+		 */
 		page = pfn_to_page(low_pfn);
+		if (page_zone(page) != zone)
+			continue;
+
+		/* Skip if free */
 		if (PageBuddy(page))
 			continue;
 
diff --git a/mm/filemap.c b/mm/filemap.c
index 97f49ed..b6627575 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1400,15 +1400,12 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
 	unsigned long seg = 0;
 	size_t count;
 	loff_t *ppos = &iocb->ki_pos;
-	struct blk_plug plug;
 
 	count = 0;
 	retval = generic_segment_checks(iov, &nr_segs, &count, VERIFY_WRITE);
 	if (retval)
 		return retval;
 
-	blk_start_plug(&plug);
-
 	/* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
 	if (filp->f_flags & O_DIRECT) {
 		loff_t size;
@@ -1424,8 +1421,12 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
 			retval = filemap_write_and_wait_range(mapping, pos,
 					pos + iov_length(iov, nr_segs) - 1);
 			if (!retval) {
+				struct blk_plug plug;
+
+				blk_start_plug(&plug);
 				retval = mapping->a_ops->direct_IO(READ, iocb,
 							iov, pos, nr_segs);
+				blk_finish_plug(&plug);
 			}
 			if (retval > 0) {
 				*ppos = pos + retval;
@@ -1481,7 +1482,6 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
 			break;
 	}
 out:
-	blk_finish_plug(&plug);
 	return retval;
 }
 EXPORT_SYMBOL(generic_file_aio_read);
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index f91b2f6..a4eb311 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -263,7 +263,12 @@ found:
 							xip_pfn);
 		if (err == -ENOMEM)
 			return VM_FAULT_OOM;
-		BUG_ON(err);
+		/*
+		 * err == -EBUSY is fine, we've raced against another thread
+		 * that faulted-in the same page
+		 */
+		if (err != -EBUSY)
+			BUG_ON(err);
 		return VM_FAULT_NOPAGE;
 	} else {
 		int err, ret = VM_FAULT_OOM;
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b3ffc21..8f7fc39 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -671,6 +671,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
 		set_pmd_at(mm, haddr, pmd, entry);
 		prepare_pmd_huge_pte(pgtable, mm);
 		add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
+		mm->nr_ptes++;
 		spin_unlock(&mm->page_table_lock);
 	}
 
@@ -789,6 +790,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	pmd = pmd_mkold(pmd_wrprotect(pmd));
 	set_pmd_at(dst_mm, addr, dst_pmd, pmd);
 	prepare_pmd_huge_pte(pgtable, dst_mm);
+	dst_mm->nr_ptes++;
 
 	ret = 0;
 out_unlock:
@@ -887,7 +889,6 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
 	}
 	kfree(pages);
 
-	mm->nr_ptes++;
 	smp_wmb(); /* make pte visible before pmd */
 	pmd_populate(mm, pmd, pgtable);
 	page_remove_rmap(page);
@@ -1047,6 +1048,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 			VM_BUG_ON(page_mapcount(page) < 0);
 			add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
 			VM_BUG_ON(!PageHead(page));
+			tlb->mm->nr_ptes--;
 			spin_unlock(&tlb->mm->page_table_lock);
 			tlb_remove_page(tlb, page);
 			pte_free(tlb->mm, pgtable);
@@ -1375,7 +1377,6 @@ static int __split_huge_page_map(struct page *page,
 			pte_unmap(pte);
 		}
 
-		mm->nr_ptes++;
 		smp_wmb(); /* make pte visible before pmd */
 		/*
 		 * Up to this point the pmd is present and huge and
@@ -1988,7 +1989,6 @@ static void collapse_huge_page(struct mm_struct *mm,
 	set_pmd_at(mm, address, pmd, _pmd);
 	update_mmu_cache(vma, address, _pmd);
 	prepare_pmd_huge_pte(pgtable, mm);
-	mm->nr_ptes--;
 	spin_unlock(&mm->page_table_lock);
 
 #ifndef CONFIG_NUMA
@@ -2083,7 +2083,7 @@ static void collect_mm_slot(struct mm_slot *mm_slot)
 {
 	struct mm_struct *mm = mm_slot->mm;
 
-	VM_BUG_ON(!spin_is_locked(&khugepaged_mm_lock));
+	VM_BUG_ON(NR_CPUS != 1 && !spin_is_locked(&khugepaged_mm_lock));
 
 	if (khugepaged_test_exit(mm)) {
 		/* free mm_slot */
@@ -2113,7 +2113,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
 	int progress = 0;
 
 	VM_BUG_ON(!pages);
-	VM_BUG_ON(!spin_is_locked(&khugepaged_mm_lock));
+	VM_BUG_ON(NR_CPUS != 1 && !spin_is_locked(&khugepaged_mm_lock));
 
 	if (khugepaged_scan.mm_slot)
 		mm_slot = khugepaged_scan.mm_slot;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5f34bd8..a876871 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2277,8 +2277,8 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
 			set_page_dirty(page);
 		list_add(&page->lru, &page_list);
 	}
-	spin_unlock(&mm->page_table_lock);
 	flush_tlb_range(vma, start, end);
+	spin_unlock(&mm->page_table_lock);
 	mmu_notifier_invalidate_range_end(mm, start, end);
 	list_for_each_entry_safe(page, tmp, &page_list, lru) {
 		page_remove_rmap(page);
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index c833add..45eb621 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -1036,7 +1036,7 @@ void __ref kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
-	if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+	if (atomic_read(&kmemleak_enabled) && ptr && size && !IS_ERR(ptr))
 		add_scan_area((unsigned long)ptr, size, gfp);
 	else if (atomic_read(&kmemleak_early_log))
 		log_early(KMEMLEAK_SCAN_AREA, ptr, size, 0);
@@ -1757,6 +1757,7 @@ void __init kmemleak_init(void)
 
 #ifdef CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF
 	if (!kmemleak_skip_disable) {
+		atomic_set(&kmemleak_early_log, 0);
 		kmemleak_disable();
 		return;
 	}
diff --git a/mm/ksm.c b/mm/ksm.c
index 1925ffb..310544a 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -28,7 +28,6 @@
 #include <linux/kthread.h>
 #include <linux/wait.h>
 #include <linux/slab.h>
-#include <linux/memcontrol.h>
 #include <linux/rbtree.h>
 #include <linux/memory.h>
 #include <linux/mmu_notifier.h>
@@ -1572,16 +1571,6 @@ struct page *ksm_does_need_to_copy(struct page *page,
 
 	new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
 	if (new_page) {
-		/*
-		 * The memcg-specific accounting when moving
-		 * pages around the LRU lists relies on the
-		 * page's owner (memcg) to be valid.  Usually,
-		 * pages are assigned to a new owner before
-		 * being put on the LRU list, but since this
-		 * is not the case here, the stale owner from
-		 * a previous allocation cycle must be reset.
-		 */
-		mem_cgroup_reset_owner(new_page);
 		copy_user_highpage(new_page, page, address, vma);
 
 		SetPageDirty(new_page);
diff --git a/mm/memblock.c b/mm/memblock.c
index 2f55f19..99f2855 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -99,21 +99,21 @@ phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t start,
 	phys_addr_t this_start, this_end, cand;
 	u64 i;
 
-	/* align @size to avoid excessive fragmentation on reserved array */
-	size = round_up(size, align);
-
 	/* pump up @end */
 	if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
 		end = memblock.current_limit;
 
-	/* adjust @start to avoid underflow and allocating the first page */
-	start = max3(start, size, (phys_addr_t)PAGE_SIZE);
+	/* avoid allocating the first page */
+	start = max_t(phys_addr_t, start, PAGE_SIZE);
 	end = max(start, end);
 
 	for_each_free_mem_range_reverse(i, nid, &this_start, &this_end, NULL) {
 		this_start = clamp(this_start, start, end);
 		this_end = clamp(this_end, start, end);
 
+		if (this_end < size)
+			continue;
+
 		cand = round_down(this_end - size, align);
 		if (cand >= this_start)
 			return cand;
@@ -728,6 +728,9 @@ static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
 {
 	phys_addr_t found;
 
+	/* align @size to avoid excessive fragmentation on reserved array */
+	size = round_up(size, align);
+
 	found = memblock_find_in_range_node(0, max_addr, size, align, nid);
 	if (found && !memblock_reserve(found, size))
 		return found;
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 556859f..d0e57a3 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -776,7 +776,8 @@ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page)
 	/* threshold event is triggered in finer grain than soft limit */
 	if (unlikely(mem_cgroup_event_ratelimit(memcg,
 						MEM_CGROUP_TARGET_THRESH))) {
-		bool do_softlimit, do_numainfo;
+		bool do_softlimit;
+		bool do_numainfo __maybe_unused;
 
 		do_softlimit = mem_cgroup_event_ratelimit(memcg,
 						MEM_CGROUP_TARGET_SOFTLIMIT);
@@ -1041,6 +1042,19 @@ struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page,
 
 	pc = lookup_page_cgroup(page);
 	memcg = pc->mem_cgroup;
+
+	/*
+	 * Surreptitiously switch any uncharged page to root:
+	 * an uncharged page off lru does nothing to secure
+	 * its former mem_cgroup from sudden removal.
+	 *
+	 * Our caller holds lru_lock, and PageCgroupUsed is updated
+	 * under page_cgroup lock: between them, they make all uses
+	 * of pc->mem_cgroup safe.
+	 */
+	if (!PageCgroupUsed(pc) && memcg != root_mem_cgroup)
+		pc->mem_cgroup = memcg = root_mem_cgroup;
+
 	mz = page_cgroup_zoneinfo(memcg, page);
 	/* compound_order() is stabilized through lru_lock */
 	MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page);
@@ -2407,8 +2421,12 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
 				       struct page *page,
 				       unsigned int nr_pages,
 				       struct page_cgroup *pc,
-				       enum charge_type ctype)
+				       enum charge_type ctype,
+				       bool lrucare)
 {
+	struct zone *uninitialized_var(zone);
+	bool was_on_lru = false;
+
 	lock_page_cgroup(pc);
 	if (unlikely(PageCgroupUsed(pc))) {
 		unlock_page_cgroup(pc);
@@ -2419,6 +2437,21 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
 	 * we don't need page_cgroup_lock about tail pages, becase they are not
 	 * accessed by any other context at this point.
 	 */
+
+	/*
+	 * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page
+	 * may already be on some other mem_cgroup's LRU.  Take care of it.
+	 */
+	if (lrucare) {
+		zone = page_zone(page);
+		spin_lock_irq(&zone->lru_lock);
+		if (PageLRU(page)) {
+			ClearPageLRU(page);
+			del_page_from_lru_list(zone, page, page_lru(page));
+			was_on_lru = true;
+		}
+	}
+
 	pc->mem_cgroup = memcg;
 	/*
 	 * We access a page_cgroup asynchronously without lock_page_cgroup().
@@ -2442,9 +2475,18 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
 		break;
 	}
 
+	if (lrucare) {
+		if (was_on_lru) {
+			VM_BUG_ON(PageLRU(page));
+			SetPageLRU(page);
+			add_page_to_lru_list(zone, page, page_lru(page));
+		}
+		spin_unlock_irq(&zone->lru_lock);
+	}
+
 	mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), nr_pages);
 	unlock_page_cgroup(pc);
-	WARN_ON_ONCE(PageLRU(page));
+
 	/*
 	 * "charge_statistics" updated event counter. Then, check it.
 	 * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree.
@@ -2642,7 +2684,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
 	ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom);
 	if (ret == -ENOMEM)
 		return ret;
-	__mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype);
+	__mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype, false);
 	return 0;
 }
 
@@ -2662,35 +2704,6 @@ static void
 __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr,
 					enum charge_type ctype);
 
-static void
-__mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg,
-					enum charge_type ctype)
-{
-	struct page_cgroup *pc = lookup_page_cgroup(page);
-	struct zone *zone = page_zone(page);
-	unsigned long flags;
-	bool removed = false;
-
-	/*
-	 * In some case, SwapCache, FUSE(splice_buf->radixtree), the page
-	 * is already on LRU. It means the page may on some other page_cgroup's
-	 * LRU. Take care of it.
-	 */
-	spin_lock_irqsave(&zone->lru_lock, flags);
-	if (PageLRU(page)) {
-		del_page_from_lru_list(zone, page, page_lru(page));
-		ClearPageLRU(page);
-		removed = true;
-	}
-	__mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
-	if (removed) {
-		add_page_to_lru_list(zone, page, page_lru(page));
-		SetPageLRU(page);
-	}
-	spin_unlock_irqrestore(&zone->lru_lock, flags);
-	return;
-}
-
 int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
 				gfp_t gfp_mask)
 {
@@ -2768,13 +2781,16 @@ static void
 __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
 					enum charge_type ctype)
 {
+	struct page_cgroup *pc;
+
 	if (mem_cgroup_disabled())
 		return;
 	if (!memcg)
 		return;
 	cgroup_exclude_rmdir(&memcg->css);
 
-	__mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
+	pc = lookup_page_cgroup(page);
+	__mem_cgroup_commit_charge(memcg, page, 1, pc, ctype, true);
 	/*
 	 * Now swap is on-memory. This means this page may be
 	 * counted both as mem and swap....double count.
@@ -3026,23 +3042,6 @@ void mem_cgroup_uncharge_end(void)
 	batch->memcg = NULL;
 }
 
-/*
- * A function for resetting pc->mem_cgroup for newly allocated pages.
- * This function should be called if the newpage will be added to LRU
- * before start accounting.
- */
-void mem_cgroup_reset_owner(struct page *newpage)
-{
-	struct page_cgroup *pc;
-
-	if (mem_cgroup_disabled())
-		return;
-
-	pc = lookup_page_cgroup(newpage);
-	VM_BUG_ON(PageCgroupUsed(pc));
-	pc->mem_cgroup = root_mem_cgroup;
-}
-
 #ifdef CONFIG_SWAP
 /*
  * called after __delete_from_swap_cache() and drop "page" account.
@@ -3247,7 +3246,7 @@ int mem_cgroup_prepare_migration(struct page *page,
 		ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
 	else
 		ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
-	__mem_cgroup_commit_charge(memcg, newpage, 1, pc, ctype);
+	__mem_cgroup_commit_charge(memcg, newpage, 1, pc, ctype, false);
 	return ret;
 }
 
@@ -3331,7 +3330,7 @@ void mem_cgroup_replace_page_cache(struct page *oldpage,
 	 * the newpage may be on LRU(or pagevec for LRU) already. We lock
 	 * LRU while we overwrite pc->mem_cgroup.
 	 */
-	__mem_cgroup_commit_charge_lrucare(newpage, memcg, type);
+	__mem_cgroup_commit_charge(memcg, newpage, 1, pc, type, true);
 }
 
 #ifdef CONFIG_DEBUG_VM
@@ -4413,6 +4412,9 @@ static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp,
 	 */
 	BUG_ON(!thresholds);
 
+	if (!thresholds->primary)
+		goto unlock;
+
 	usage = mem_cgroup_usage(memcg, type == _MEMSWAP);
 
 	/* Check if a threshold crossed before removing */
@@ -4461,7 +4463,7 @@ swap_buffers:
 
 	/* To be sure that nobody uses thresholds */
 	synchronize_rcu();
-
+unlock:
 	mutex_unlock(&memcg->thresholds_lock);
 }
 
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 06b145fb..47296fe 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -640,10 +640,11 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
 	unsigned long vmstart;
 	unsigned long vmend;
 
-	vma = find_vma_prev(mm, start, &prev);
+	vma = find_vma(mm, start);
 	if (!vma || vma->vm_start > start)
 		return -EFAULT;
 
+	prev = vma->vm_prev;
 	if (start > vma->vm_start)
 		prev = vma;
 
diff --git a/mm/migrate.c b/mm/migrate.c
index 9871a56..1503b6b 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -445,7 +445,6 @@ void migrate_page_copy(struct page *newpage, struct page *page)
 	ClearPageSwapCache(page);
 	ClearPagePrivate(page);
 	set_page_private(page, 0);
-	page->mapping = NULL;
 
 	/*
 	 * If any waiters have accumulated on the new page then
@@ -667,6 +666,7 @@ static int move_to_new_page(struct page *newpage, struct page *page,
 	} else {
 		if (remap_swapcache)
 			remove_migration_ptes(page, newpage);
+		page->mapping = NULL;
 	}
 
 	unlock_page(newpage);
@@ -839,8 +839,6 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
 	if (!newpage)
 		return -ENOMEM;
 
-	mem_cgroup_reset_owner(newpage);
-
 	if (page_count(page) == 1) {
 		/* page was freed from under us. So we are done. */
 		goto out;
diff --git a/mm/mlock.c b/mm/mlock.c
index 4f4f53b..ef726e8 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -385,10 +385,11 @@ static int do_mlock(unsigned long start, size_t len, int on)
 		return -EINVAL;
 	if (end == start)
 		return 0;
-	vma = find_vma_prev(current->mm, start, &prev);
+	vma = find_vma(current->mm, start);
 	if (!vma || vma->vm_start > start)
 		return -ENOMEM;
 
+	prev = vma->vm_prev;
 	if (start > vma->vm_start)
 		prev = vma;
 
diff --git a/mm/mmap.c b/mm/mmap.c
index 3f758c7..da15a79 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1266,8 +1266,9 @@ munmap_back:
 	vma->vm_pgoff = pgoff;
 	INIT_LIST_HEAD(&vma->anon_vma_chain);
 
+	error = -EINVAL;	/* when rejecting VM_GROWSDOWN|VM_GROWSUP */
+
 	if (file) {
-		error = -EINVAL;
 		if (vm_flags & (VM_GROWSDOWN|VM_GROWSUP))
 			goto free_vma;
 		if (vm_flags & VM_DENYWRITE) {
@@ -1293,6 +1294,8 @@ munmap_back:
 		pgoff = vma->vm_pgoff;
 		vm_flags = vma->vm_flags;
 	} else if (vm_flags & VM_SHARED) {
+		if (unlikely(vm_flags & (VM_GROWSDOWN|VM_GROWSUP)))
+			goto free_vma;
 		error = shmem_zero_setup(vma);
 		if (error)
 			goto free_vma;
@@ -1605,7 +1608,6 @@ EXPORT_SYMBOL(find_vma);
 
 /*
  * Same as find_vma, but also return a pointer to the previous VMA in *pprev.
- * Note: pprev is set to NULL when return value is NULL.
  */
 struct vm_area_struct *
 find_vma_prev(struct mm_struct *mm, unsigned long addr,
@@ -1614,7 +1616,16 @@ find_vma_prev(struct mm_struct *mm, unsigned long addr,
 	struct vm_area_struct *vma;
 
 	vma = find_vma(mm, addr);
-	*pprev = vma ? vma->vm_prev : NULL;
+	if (vma) {
+		*pprev = vma->vm_prev;
+	} else {
+		struct rb_node *rb_node = mm->mm_rb.rb_node;
+		*pprev = NULL;
+		while (rb_node) {
+			*pprev = rb_entry(rb_node, struct vm_area_struct, vm_rb);
+			rb_node = rb_node->rb_right;
+		}
+	}
 	return vma;
 }
 
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 5a688a2..f437d05 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -262,10 +262,11 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
 
 	down_write(&current->mm->mmap_sem);
 
-	vma = find_vma_prev(current->mm, start, &prev);
+	vma = find_vma(current->mm, start);
 	error = -ENOMEM;
 	if (!vma)
 		goto out;
+	prev = vma->vm_prev;
 	if (unlikely(grows & PROT_GROWSDOWN)) {
 		if (vma->vm_start >= end)
 			goto out;
diff --git a/mm/nommu.c b/mm/nommu.c
index b982290..f59e170 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -696,9 +696,11 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
 	if (vma->vm_file) {
 		mapping = vma->vm_file->f_mapping;
 
+		mutex_lock(&mapping->i_mmap_mutex);
 		flush_dcache_mmap_lock(mapping);
 		vma_prio_tree_insert(vma, &mapping->i_mmap);
 		flush_dcache_mmap_unlock(mapping);
+		mutex_unlock(&mapping->i_mmap_mutex);
 	}
 
 	/* add the VMA to the tree */
@@ -760,9 +762,11 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
 	if (vma->vm_file) {
 		mapping = vma->vm_file->f_mapping;
 
+		mutex_lock(&mapping->i_mmap_mutex);
 		flush_dcache_mmap_lock(mapping);
 		vma_prio_tree_remove(vma, &mapping->i_mmap);
 		flush_dcache_mmap_unlock(mapping);
+		mutex_unlock(&mapping->i_mmap_mutex);
 	}
 
 	/* remove from the MM's tree and list */
@@ -775,8 +779,6 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
 
 	if (vma->vm_next)
 		vma->vm_next->vm_prev = vma->vm_prev;
-
-	vma->vm_mm = NULL;
 }
 
 /*
@@ -2052,6 +2054,7 @@ int nommu_shrink_inode_mappings(struct inode *inode, size_t size,
 	high = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 
 	down_write(&nommu_region_sem);
+	mutex_lock(&inode->i_mapping->i_mmap_mutex);
 
 	/* search for VMAs that fall within the dead zone */
 	vma_prio_tree_foreach(vma, &iter, &inode->i_mapping->i_mmap,
@@ -2059,6 +2062,7 @@ int nommu_shrink_inode_mappings(struct inode *inode, size_t size,
 		/* found one - only interested if it's shared out of the page
 		 * cache */
 		if (vma->vm_flags & VM_SHARED) {
+			mutex_unlock(&inode->i_mapping->i_mmap_mutex);
 			up_write(&nommu_region_sem);
 			return -ETXTBSY; /* not quite true, but near enough */
 		}
@@ -2086,6 +2090,7 @@ int nommu_shrink_inode_mappings(struct inode *inode, size_t size,
 		}
 	}
 
+	mutex_unlock(&inode->i_mapping->i_mmap_mutex);
 	up_write(&nommu_region_sem);
 	return 0;
 }
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d2186ec..a13ded1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5236,6 +5236,7 @@ void *__init alloc_large_system_hash(const char *tablename,
 		max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
 		do_div(max, bucketsize);
 	}
+	max = min(max, 0x80000000ULL);
 
 	if (numentries > max)
 		numentries = max;
diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index de1616a..1ccbd71 100644
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -379,13 +379,15 @@ static struct swap_cgroup *lookup_swap_cgroup(swp_entry_t ent,
 	pgoff_t offset = swp_offset(ent);
 	struct swap_cgroup_ctrl *ctrl;
 	struct page *mappage;
+	struct swap_cgroup *sc;
 
 	ctrl = &swap_cgroup_ctrl[swp_type(ent)];
 	if (ctrlp)
 		*ctrlp = ctrl;
 
 	mappage = ctrl->map[offset / SC_PER_PAGE];
-	return page_address(mappage) + offset % SC_PER_PAGE;
+	sc = page_address(mappage);
+	return sc + offset % SC_PER_PAGE;
 }
 
 /**
diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c
index 12a48a88..405d331 100644
--- a/mm/percpu-vm.c
+++ b/mm/percpu-vm.c
@@ -184,8 +184,7 @@ static void pcpu_unmap_pages(struct pcpu_chunk *chunk,
 				   page_end - page_start);
 	}
 
-	for (i = page_start; i < page_end; i++)
-		__clear_bit(i, populated);
+	bitmap_clear(populated, page_start, page_end - page_start);
 }
 
 /**
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index e920aa3..c20ff48 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -298,23 +298,18 @@ static ssize_t process_vm_rw_core(pid_t pid, const struct iovec *lvec,
 		goto free_proc_pages;
 	}
 
-	task_lock(task);
-	if (__ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
-		task_unlock(task);
-		rc = -EPERM;
-		goto put_task_struct;
-	}
-	mm = task->mm;
-
-	if (!mm || (task->flags & PF_KTHREAD)) {
-		task_unlock(task);
-		rc = -EINVAL;
+	mm = mm_access(task, PTRACE_MODE_ATTACH);
+	if (!mm || IS_ERR(mm)) {
+		rc = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH;
+		/*
+		 * Explicitly map EACCES to EPERM as EPERM is a more a
+		 * appropriate error code for process_vw_readv/writev
+		 */
+		if (rc == -EACCES)
+			rc = -EPERM;
 		goto put_task_struct;
 	}
 
-	atomic_inc(&mm->mm_users);
-	task_unlock(task);
-
 	for (i = 0; i < riovcnt && iov_l_curr_idx < liovcnt; i++) {
 		rc = process_vm_rw_single_vec(
 			(unsigned long)rvec[i].iov_base, rvec[i].iov_len,
diff --git a/mm/swap.c b/mm/swap.c
index b0f529b..14380e9 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -652,14 +652,14 @@ EXPORT_SYMBOL(__pagevec_release);
 void lru_add_page_tail(struct zone* zone,
 		       struct page *page, struct page *page_tail)
 {
-	int active;
+	int uninitialized_var(active);
 	enum lru_list lru;
 	const int file = 0;
 
 	VM_BUG_ON(!PageHead(page));
 	VM_BUG_ON(PageCompound(page_tail));
 	VM_BUG_ON(PageLRU(page_tail));
-	VM_BUG_ON(!spin_is_locked(&zone->lru_lock));
+	VM_BUG_ON(NR_CPUS != 1 && !spin_is_locked(&zone->lru_lock));
 
 	SetPageLRU(page_tail);
 
@@ -672,7 +672,6 @@ void lru_add_page_tail(struct zone* zone,
 			active = 0;
 			lru = LRU_INACTIVE_ANON;
 		}
-		update_page_reclaim_stat(zone, page_tail, file, active);
 	} else {
 		SetPageUnevictable(page_tail);
 		lru = LRU_UNEVICTABLE;
@@ -693,6 +692,9 @@ void lru_add_page_tail(struct zone* zone,
 		list_head = page_tail->lru.prev;
 		list_move_tail(&page_tail->lru, list_head);
 	}
+
+	if (!PageUnevictable(page))
+		update_page_reclaim_stat(zone, page_tail, file, active);
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
@@ -710,8 +712,8 @@ static void __pagevec_lru_add_fn(struct page *page, void *arg)
 	SetPageLRU(page);
 	if (active)
 		SetPageActive(page);
-	update_page_reclaim_stat(zone, page, file, active);
 	add_page_to_lru_list(zone, page, lru);
+	update_page_reclaim_stat(zone, page, file, active);
 }
 
 /*
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 470038a..ea6b32d 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -300,16 +300,6 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
 			new_page = alloc_page_vma(gfp_mask, vma, addr);
 			if (!new_page)
 				break;		/* Out of memory */
-			/*
-			 * The memcg-specific accounting when moving
-			 * pages around the LRU lists relies on the
-			 * page's owner (memcg) to be valid.  Usually,
-			 * pages are assigned to a new owner before
-			 * being put on the LRU list, but since this
-			 * is not the case here, the stale owner from
-			 * a previous allocation cycle must be reset.
-			 */
-			mem_cgroup_reset_owner(new_page);
 		}
 
 		/*