diff options
author | Zi Yan <ziy@nvidia.com> | 2022-03-30 15:45:43 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-30 15:45:43 -0700 |
commit | 787af64d05cd528aac9ad16752d11bb1c6061bb9 (patch) | |
tree | 0c18b1f5d46494dab9cd643bd303b7cbc4991a99 | |
parent | d5fd43bac8396c9b213faf14cd4560d73b30f618 (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.c | 3 |
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 |