From: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Fixes: 6bc9b56433b76 ("mm: fix race on soft-offlining") Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Xishi Qiu <xishi.qiuxishi@xxxxxxxxxxxxxxx> Cc: "Chen, Jerry T" <jerry.t.chen@xxxxxxxxx> Cc: "Zhuo, Qiuxu" <qiuxu.zhuo@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> [4.19+] Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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; _