From: Naoya Horiguchi Subject: Revert "mm/memory-failure.c: fix race with changing page compound again" Reverts commit 888af2701db7 ("mm/memory-failure.c: fix race with changing page compound again") because now we fetch the page refcount under hugetlb_lock in try_memory_failure_hugetlb() so that the race check is no longer necessary. Link: https://lkml.kernel.org/r/20220408135323.1559401-4-naoya.horiguchi@linux.dev Signed-off-by: Naoya Horiguchi Suggested-by: Miaohe Lin Reviewed-by: Miaohe Lin Reviewed-by: Mike Kravetz Cc: Miaohe Lin Cc: Yang Shi Cc: Dan Carpenter Signed-off-by: Andrew Morton --- include/linux/mm.h | 1 - include/ras/ras_event.h | 1 - mm/memory-failure.c | 11 ----------- 3 files changed, 13 deletions(-) --- a/include/linux/mm.h~revert-mm-memory-failurec-fix-race-with-changing-page-compound-again +++ a/include/linux/mm.h @@ -3292,7 +3292,6 @@ enum mf_action_page_type { MF_MSG_BUDDY, MF_MSG_DAX, MF_MSG_UNSPLIT_THP, - MF_MSG_DIFFERENT_PAGE_SIZE, MF_MSG_UNKNOWN, }; --- a/include/ras/ras_event.h~revert-mm-memory-failurec-fix-race-with-changing-page-compound-again +++ a/include/ras/ras_event.h @@ -374,7 +374,6 @@ TRACE_EVENT(aer_event, EM ( MF_MSG_BUDDY, "free buddy page" ) \ EM ( MF_MSG_DAX, "dax page" ) \ EM ( MF_MSG_UNSPLIT_THP, "unsplit thp" ) \ - EM ( MF_MSG_DIFFERENT_PAGE_SIZE, "different page size" ) \ EMe ( MF_MSG_UNKNOWN, "unknown page" ) /* --- a/mm/memory-failure.c~revert-mm-memory-failurec-fix-race-with-changing-page-compound-again +++ a/mm/memory-failure.c @@ -734,7 +734,6 @@ static const char * const action_page_ty [MF_MSG_BUDDY] = "free buddy page", [MF_MSG_DAX] = "dax page", [MF_MSG_UNSPLIT_THP] = "unsplit thp", - [MF_MSG_DIFFERENT_PAGE_SIZE] = "different page size", [MF_MSG_UNKNOWN] = "unknown page", }; @@ -1606,16 +1605,6 @@ retry: return res == MF_RECOVERED ? 0 : -EBUSY; } - /* - * The page could have changed compound pages due to race window. - * If this happens just bail out. - */ - if (!PageHuge(p) || compound_head(p) != head) { - action_result(pfn, MF_MSG_DIFFERENT_PAGE_SIZE, MF_IGNORED); - res = -EBUSY; - goto out; - } - page_flags = head->flags; /* _