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authorNaoya Horiguchi <naoya.horiguchi@nec.com>2023-02-21 17:59:05 +0900
committerAndrew Morton <akpm@linux-foundation.org>2023-02-27 17:00:14 -0800
commit6da6b1d4a7df8c35770186b53ef65d388398e139 (patch)
treedecf0e93e67c58b9256cc5093982e0266705c188 /include/linux
parent1c0a0af511effbd75beffa6c5e54fd64d3563860 (diff)
mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON
After a memory error happens on a clean folio, a process unexpectedly receives SIGBUS when it accesses the error page. This SIGBUS killing is pointless and simply degrades the level of RAS of the system, because the clean folio can be dropped without any data lost on memory error handling as we do for a clean pagecache. When memory_failure() is called on a clean folio, try_to_unmap() is called twice (one from split_huge_page() and one from hwpoison_user_mappings()). The root cause of the issue is that pte conversion to hwpoisoned entry is now done in the first call of try_to_unmap() because PageHWPoison is already set at this point, while it's actually expected to be done in the second call. This behavior disturbs the error handling operation like removing pagecache, which results in the malfunction described above. So convert TTU_IGNORE_HWPOISON into TTU_HWPOISON and set TTU_HWPOISON only when we really intend to convert pte to hwpoison entry. This can prevent other callers of try_to_unmap() from accidentally converting to hwpoison entries. Link: https://lkml.kernel.org/r/20230221085905.1465385-1-naoya.horiguchi@linux.dev Fixes: a42634a6c07d ("readahead: Use a folio in read_pages()") Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/rmap.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index a4570da03e58..b87d01660412 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -94,7 +94,7 @@ enum ttu_flags {
TTU_SPLIT_HUGE_PMD = 0x4, /* split huge PMD if any */
TTU_IGNORE_MLOCK = 0x8, /* ignore mlock */
TTU_SYNC = 0x10, /* avoid racy checks with PVMW_SYNC */
- TTU_IGNORE_HWPOISON = 0x20, /* corrupted page is recoverable */
+ TTU_HWPOISON = 0x20, /* do convert pte to hwpoison entry */
TTU_BATCH_FLUSH = 0x40, /* Batch TLB flushes where possible
* and caller guarantees they will
* do a final flush if necessary */