From: Ebru Akagunduz <[email protected]>

After creating revalidate vma function, locking inconsistency occured
due to directing the code path to wrong label. This patch directs
to correct label and fix the inconsistency.

Related commit that caused inconsistency:
http://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=da4360877094368f6dfe75bbe804b0f0a5d575b0

Link: 
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ebru Akagunduz <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
 mm/huge_memory.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 7bb30e853335..1777b806de96 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2487,13 +2487,18 @@ static void collapse_huge_page(struct mm_struct *mm,
 
        down_read(&mm->mmap_sem);
        result = hugepage_vma_revalidate(mm, address);
-       if (result)
-               goto out;
+       if (result) {
+               mem_cgroup_cancel_charge(new_page, memcg, true);
+               up_read(&mm->mmap_sem);
+               goto out_nolock;
+       }
 
        pmd = mm_find_pmd(mm, address);
        if (!pmd) {
                result = SCAN_PMD_NULL;
-               goto out;
+               mem_cgroup_cancel_charge(new_page, memcg, true);
+               up_read(&mm->mmap_sem);
+               goto out_nolock;
        }
 
        /*
@@ -2502,8 +2507,9 @@ static void collapse_huge_page(struct mm_struct *mm,
         * label out. Continuing to collapse causes inconsistency.
         */
        if (!__collapse_huge_page_swapin(mm, vma, address, pmd)) {
+               mem_cgroup_cancel_charge(new_page, memcg, true);
                up_read(&mm->mmap_sem);
-               goto out;
+               goto out_nolock;
        }
 
        up_read(&mm->mmap_sem);
-- 
2.8.1

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