From: Oscar Salvador <osalvador@suse.de> mainline inclusion from linux-v5.10-rc1 commit 5a2ffca3c23333a41cf8604f62994cfd28e4267b category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4LE22 CVE: NA -------------------------------- Currently, there is an inconsistency when calling soft-offline from different paths on a page that is already poisoned. 1) madvise: madvise_inject_error skips any poisoned page and continues the loop. If that was the only page to madvise, it returns 0. 2) /sys/devices/system/memory/: When calling soft_offline_page_store()->soft_offline_page(), we return -EBUSY in case the page is already poisoned. This is inconsistent with a) the above example and b) memory_failure, where we return 0 if the page was poisoned. Fix this by dropping the PageHWPoison() check in madvise_inject_error, and let soft_offline_page return 0 if it finds the page already poisoned. Please, note that this represents a user-api change, since now the return error when calling soft_offline_page_store()->soft_offline_page() will be different. Signed-off-by: Oscar Salvador <osalvador@suse.de> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- mm/madvise.c | 5 ----- mm/memory-failure.c | 4 ++-- 2 files changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index 6022627646fa2..f0d3d0aaa1167 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -662,11 +662,6 @@ static int madvise_inject_error(int behavior, */ order = compound_order(compound_head(page)); - if (PageHWPoison(page)) { - put_page(page); - continue; - } - if (behavior == MADV_SOFT_OFFLINE) { pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n", pfn, start); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 6f16e24969843..385d2d570435c 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1796,7 +1796,7 @@ static int __soft_offline_page(struct page *page) unlock_page(page); put_page(page); pr_info("soft offline: %#lx page already poisoned\n", pfn); - return -EBUSY; + return 0; } if (!PageHuge(page)) @@ -1902,7 +1902,7 @@ int soft_offline_page(struct page *page, int flags) pr_info("soft offline: %#lx page already poisoned\n", pfn); if (flags & MF_COUNT_INCREASED) put_page(page); - return -EBUSY; + return 0; } get_online_mems(); -- 2.25.1