[PATCH 3.16 011/114] s390/scm_blk: fix deadlock for requests != REQ_TYPE_FS

[Ben Hutchings]

3.16.36-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Sebastian Ott <sebott@xxxxxxxxxxxxxxxxxx>

commit b707c65ae70e24c47a0ce4a7279224ce8f0ffb7f upstream.

When we refuse a non REQ_TYPE_FS request in the build request function
we already hold the queue lock. Thus we must not call blk_end_request_all
but __blk_end_request_all.

Reported-by: Peter Oberparleiter <oberpar@xxxxxxxxxxxxxxxxxx>
Fixes: de9587a ('s390/scm_blk: fix endless loop for requests != REQ_TYPE_FS')
Signed-off-by: Sebastian Ott <sebott@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/s390/block/scm_blk.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/s390/block/scm_blk.c
+++ b/drivers/s390/block/scm_blk.c
@@ -210,7 +210,7 @@ static void scm_blk_request(struct reque
 		if (req->cmd_type != REQ_TYPE_FS) {
 			blk_start_request(req);
 			blk_dump_rq_flags(req, KMSG_COMPONENT " bad request");
-			blk_end_request_all(req, -EIO);
+			__blk_end_request_all(req, -EIO);
 			continue;
 		}