Subject: + hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage.patch added to -mm tree To: sla...@gmail.com,a...@linux.intel.com,n-horigu...@ah.jp.nec.com,stable@vger.kernel.org From: a...@linux-foundation.org Date: Mon, 12 May 2014 15:56:24 -0700
The patch titled Subject: HWPOSION, hugetlb: lock_page/unlock_page does not match for handling a free hugepage has been added to the -mm tree. Its filename is hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Chen Yucong <sla...@gmail.com> Subject: HWPOSION, hugetlb: lock_page/unlock_page does not match for handling a free hugepage For handling a free hugepage in memory failure, the race will happen if another thread hwpoisoned this hugepage concurrently. So we need to check PageHWPoison instead of !PageHWPoison. If hwpoison_filter(p) returns true or a race happens, then we need to unlock_page(hpage). Signed-off-by: Chen Yucong <sla...@gmail.com> Reviewed-by: Naoya Horiguchi <n-horigu...@ah.jp.nec.com> Tested-by: Naoya Horiguchi <n-horigu...@ah.jp.nec.com> Reviewed-by: Andi Kleen <a...@linux.intel.com> Cc: <stable@vger.kernel.org> [2.6.36+] Signed-off-by: Andrew Morton <a...@linux-foundation.org> --- mm/memory-failure.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff -puN mm/memory-failure.c~hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage mm/memory-failure.c --- a/mm/memory-failure.c~hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage +++ a/mm/memory-failure.c @@ -1081,15 +1081,16 @@ int memory_failure(unsigned long pfn, in return 0; } else if (PageHuge(hpage)) { /* - * Check "just unpoisoned", "filter hit", and - * "race with other subpage." + * Check "filter hit" and "race with other subpage." */ lock_page(hpage); - if (!PageHWPoison(hpage) - || (hwpoison_filter(p) && TestClearPageHWPoison(p)) - || (p != hpage && TestSetPageHWPoison(hpage))) { - atomic_long_sub(nr_pages, &num_poisoned_pages); - return 0; + if (PageHWPoison(hpage)) { + if ((hwpoison_filter(p) && TestClearPageHWPoison(p)) + || (p != hpage && TestSetPageHWPoison(hpage))) { + atomic_long_sub(nr_pages, &num_poisoned_pages); + unlock_page(hpage); + return 0; + } } set_page_hwpoison_huge_page(hpage); res = dequeue_hwpoisoned_huge_page(hpage); _ Patches currently in -mm which might be from sla...@gmail.com are hwposion-hugetlb-lock_page-unlock_page-does-not-match-for-handling-a-free-hugepage.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html