summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorZi Yan <ziy@nvidia.com>2022-03-30 15:45:43 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-03-30 15:45:43 -0700
commit787af64d05cd528aac9ad16752d11bb1c6061bb9 (patch)
tree0c18b1f5d46494dab9cd643bd303b7cbc4991a99
parentd5fd43bac8396c9b213faf14cd4560d73b30f618 (diff)
mm: page_alloc: validate buddy before check its migratetype.
Whenever a buddy page is found, page_is_buddy() should be called to check its validity. Add the missing check during pageblock merge check. Fixes: 1dd214b8f21c ("mm: page_alloc: avoid merging non-fallbackable pageblocks with others") Link: https://lore.kernel.org/all/20220330154208.71aca532@gandalf.local.home/ Reported-and-tested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Zi Yan <ziy@nvidia.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--mm/page_alloc.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index bdc8f60ae462..6c6af8658775 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1108,6 +1108,9 @@ continue_merging:
buddy_pfn = __find_buddy_pfn(pfn, order);
buddy = page + (buddy_pfn - pfn);
+
+ if (!page_is_buddy(page, buddy, order))
+ goto done_merging;
buddy_mt = get_pageblock_migratetype(buddy);
if (migratetype != buddy_mt