From: Naoya Horiguchi n-horiguchi@ah.jp.nec.com Subject: mm: soft-offline: return -EBUSY if set_hwpoison_free_buddy_page() fails

The pass/fail of soft offline should be judged by checking whether the raw error page was finally contained or not (i.e. the result of set_hwpoison_free_buddy_page()), but current code do not work like that. It might lead us to misjudge the test result when set_hwpoison_free_buddy_page() fails.

Without this fix, there are cases where madvise(MADV_SOFT_OFFLINE) may not offline the original page and will not return an error.

Link: http://lkml.kernel.org/r/1560154686-18497-2-git-send-email-n-horiguchi@ah.jp... Signed-off-by: Naoya Horiguchi n-horiguchi@ah.jp.nec.com Fixes: 6bc9b56433b76 ("mm: fix race on soft-offlining") Reviewed-by: Mike Kravetz mike.kravetz@oracle.com Reviewed-by: Oscar Salvador osalvador@suse.de Cc: Michal Hocko mhocko@kernel.org Cc: Xishi Qiu xishi.qiuxishi@alibaba-inc.com Cc: "Chen, Jerry T" jerry.t.chen@intel.com Cc: "Zhuo, Qiuxu" qiuxu.zhuo@intel.com Cc: stable@vger.kernel.org [4.19+] Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/memory-failure.c | 2 ++ 1 file changed, 2 insertions(+)

--- a/mm/memory-failure.c~mm-soft-offline-return-ebusy-if-set_hwpoison_free_buddy_page-fails +++ a/mm/memory-failure.c @@ -1730,6 +1730,8 @@ static int soft_offline_huge_page(struct if (!ret) { if (set_hwpoison_free_buddy_page(page)) num_poisoned_pages_inc(); + else + ret = -EBUSY; } } return ret; _