diff options
| author | Michael Wang <yun.wang@linux.alibaba.com> | 2021-09-03 00:58:40 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-03 19:58:16 +0300 |
| commit | f87060d345232c7d855167a43faf006e24afa999 (patch) | |
| tree | c19688b957a573a3b742d415b3f28b89781922be | |
| parent | 941ca063eb8ed01e66336b1f493e95b107024bc8 (diff) | |
| download | linux-f87060d345232c7d855167a43faf006e24afa999.tar.xz | |
mm: fix panic caused by __page_handle_poison()
In commit 510d25c92ec4 ("mm/hwpoison: disable pcp for
page_handle_poison()"), __page_handle_poison() was introduced, and if we
mark:
RET_A = dissolve_free_huge_page();
RET_B = take_page_off_buddy();
then __page_handle_poison was supposed to return TRUE When RET_A == 0 &&
RET_B == TRUE
But since it failed to take care the case when RET_A is -EBUSY or -ENOMEM,
and just return the ret as a bool which actually become TRUE, it break the
original logic.
The following result is a huge page in freelist but was
referenced as poisoned, and lead into the final panic:
kernel BUG at mm/internal.h:95!
invalid opcode: 0000 [#1] SMP PTI
skip...
RIP: 0010:set_page_refcounted mm/internal.h:95 [inline]
RIP: 0010:remove_hugetlb_page+0x23c/0x240 mm/hugetlb.c:1371
skip...
Call Trace:
remove_pool_huge_page+0xe4/0x110 mm/hugetlb.c:1892
return_unused_surplus_pages+0x8d/0x150 mm/hugetlb.c:2272
hugetlb_acct_memory.part.91+0x524/0x690 mm/hugetlb.c:4017
This patch replaces 'bool' with 'int' to handle RET_A correctly.
Link: https://lkml.kernel.org/r/61782ac6-1e8a-4f6f-35e6-e94fce3b37f5@linux.alibaba.com
Fixes: 510d25c92ec4 ("mm/hwpoison: disable pcp for page_handle_poison()")
Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: Abaci <abaci@linux.alibaba.com>
Cc: <stable@vger.kernel.org> [5.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/memory-failure.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b3e8c75bee66..2f925615e573 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -68,7 +68,7 @@ atomic_long_t num_poisoned_pages __read_mostly = ATOMIC_LONG_INIT(0); static bool __page_handle_poison(struct page *page) { - bool ret; + int ret; zone_pcp_disable(page_zone(page)); ret = dissolve_free_huge_page(page); @@ -76,7 +76,7 @@ static bool __page_handle_poison(struct page *page) ret = take_page_off_buddy(page); zone_pcp_enable(page_zone(page)); - return ret; + return ret > 0; } static bool page_handle_poison(struct page *page, bool hugepage_or_freepage, bool release) |