[PATCH 4.12 07/65] xfs: Fix leak of discard bio

[Greg Kroah-Hartman]

4.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jan Kara <jack@xxxxxxx>

commit ea7bd56fa309d10a41b1041827a63c0746c47554 upstream.

The bio describing discard operation is allocated by
__blkdev_issue_discard() which returns us a reference to it. That
reference is never released and thus we leak this bio. Drop the bio
reference once it completes in xlog_discard_endio().

Fixes: 4560e78f40cb55bd2ea8f1ef4001c5baa88531c7
Signed-off-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/xfs/xfs_log_cil.c |    1 +
 1 file changed, 1 insertion(+)

--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -519,6 +519,7 @@ xlog_discard_endio(
 
 	INIT_WORK(&ctx->discard_endio_work, xlog_discard_endio_work);
 	queue_work(xfs_discard_wq, &ctx->discard_endio_work);
+	bio_put(bio);
 }
 
 static void