[PATCH] block: clear zone write plugging flag before failing rejected BIOs

[PATCH] block: clear zone write plugging flag before failing rejected BIOs

[Jackie Liu]

From: Jackie Liu <liuyun01@kylinos.cn>

Commit fe0418eb9bd6 ("block: Prevent potential deadlocks in zone write plug
error recovery") changed blk_zone_wplug_handle_write() to fail BIOs
directly when blk_zone_wplug_prepare_bio() rejects them, for example
because the write is not aligned to the cached write pointer or the plug
needs a write pointer update. However, the BIO is already marked with
BIO_ZONE_WRITE_PLUGGING at that point even though it is not issued.

Completing such a BIO with bio_io_error() makes bio_endio() call
blk_zone_write_plug_bio_endio(), which treats the completion as a failed
device write and may poison the cached zone write pointer state by setting
BLK_ZONE_WPLUG_NEED_WP_UPDATE.

Clear BIO_ZONE_WRITE_PLUGGING and drop the zone write plug reference before
failing the rejected BIO.

Fixes: fe0418eb9bd6 ("block: Prevent potential deadlocks in zone write plug error recovery")
Cc: stable@vger.kernel.org # 6.13+
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
---
 block/blk-zoned.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 6a221c180889..855767d8bfc1 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -1502,7 +1502,9 @@ static bool blk_zone_wplug_handle_write(struct bio *bio, unsigned int nr_segs)
 		goto queue_bio;
 
 	if (!blk_zone_wplug_prepare_bio(zwplug, bio)) {
+		bio_clear_flag(bio, BIO_ZONE_WRITE_PLUGGING);
 		spin_unlock_irqrestore(&zwplug->lock, flags);
+		disk_put_zone_wplug(zwplug);
 		bio_io_error(bio);
 		return true;
 	}
-- 
2.54.0