mm: memory-failure: fix unexpected return value in soft_offline_page()

When page_handle_poison() fails to handle the hugepage or free page in
retry path, soft_offline_page() will return 0 while -EBUSY is expected in
this case.

Consequently the user will think soft_offline_page succeeds while it in
fact failed.  So the user will not try again later in this case.

Link: https://lkml.kernel.org/r/20230627112808.1275241-1-linmiaohe@huawei.com
Fixes: b94e02822deb ("mm,hwpoison: try to narrow window race for free pages")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 139b31fdb6788c046ee9964a0f370a21f8953d2b..fe121fdb05f7f57b888ef9db61dcadb213211a53 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2741,10 +2741,13 @@ retry:
        if (ret > 0) {
                ret = soft_offline_in_use_page(page);
        } else if (ret == 0) {
-               if (!page_handle_poison(page, true, false) && try_again) {
-                       try_again = false;
-                       flags &= ~MF_COUNT_INCREASED;
-                       goto retry;
+               if (!page_handle_poison(page, true, false)) {
+                       if (try_again) {
+                               try_again = false;
+                               flags &= ~MF_COUNT_INCREASED;
+                               goto retry;
+                       }
+                       ret = -EBUSY;
                }
        }