mm: thp: fix up pmd_trans_unstable() locations
pmd_trans_unstable() should be called before pmd_offset_map() in the
locations where the mmap_sem is held for reading.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mark Salter <msalter@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 9694cc2..c283832 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -781,9 +781,6 @@
int err = 0;
pagemap_entry_t pme = make_pme(PM_NOT_PRESENT);
- if (pmd_trans_unstable(pmd))
- return 0;
-
/* find the first VMA at or above 'addr' */
vma = find_vma(walk->mm, addr);
spin_lock(&walk->mm->page_table_lock);
@@ -802,6 +799,8 @@
return err;
}
+ if (pmd_trans_unstable(pmd))
+ return 0;
for (; addr != end; addr += PAGE_SIZE) {
/* check to see if we've left 'vma' behind