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From:   Miaohe Lin <linmiaohe@huawei.com>
To:     <akpm@linux-foundation.org>, <naoya.horiguchi@nec.com>
CC:     <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        <linmiaohe@huawei.com>
Subject: [PATCH] mm: memory-failure: fix unexpected return value in soft_offline_page()
Date:   Tue, 27 Jun 2023 19:28:08 +0800
Message-ID: <20230627112808.1275241-1-linmiaohe@huawei.com>
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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.

Fixes: b94e02822deb ("mm,hwpoison: try to narrow window race for free pages")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 mm/memory-failure.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index aada6ac72fe5..dc1572818b7d 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2737,10 +2737,13 @@ int soft_offline_page(unsigned long pfn, int flags)
 	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;
 		}
 	}
 
-- 
2.27.0