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From:   Jaegeuk Kim <jaegeuk@kernel.org>
To:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Cc:     Jaegeuk Kim <jaegeuk@kernel.org>, stable@vger.kernel.org
Subject: [PATCH] f2fs: get out of a repeat loop when getting a locked data page
Date:   Thu, 23 Mar 2023 14:39:19 -0700
Message-Id: <20230323213919.1876157-1-jaegeuk@kernel.org>
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https://bugzilla.kernel.org/show_bug.cgi?id=216050

Somehow we're getting a page which has a different mapping.
Let's avoid the infinite loop.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/data.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index bf51e6e4eb64..80702c93e885 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1329,18 +1329,14 @@ struct page *f2fs_get_lock_data_page(struct inode *inode, pgoff_t index,
 {
 	struct address_space *mapping = inode->i_mapping;
 	struct page *page;
-repeat:
+
 	page = f2fs_get_read_data_page(inode, index, 0, for_write, NULL);
 	if (IS_ERR(page))
 		return page;
 
 	/* wait for read completion */
 	lock_page(page);
-	if (unlikely(page->mapping != mapping)) {
-		f2fs_put_page(page, 1);
-		goto repeat;
-	}
-	if (unlikely(!PageUptodate(page))) {
+	if (unlikely(page->mapping != mapping || !PageUptodate(page))) {
 		f2fs_put_page(page, 1);
 		return ERR_PTR(-EIO);
 	}
-- 
2.40.0.348.gf938b09366-goog