dm mpath: do not lock up a CPU with requeuing activity
authorBart Van Assche <bart.vanassche@wdc.com>
Wed, 9 Aug 2017 18:32:12 +0000 (11:32 -0700)
committerMike Snitzer <snitzer@redhat.com>
Mon, 28 Aug 2017 13:58:27 +0000 (09:58 -0400)
When using the block layer in single queue mode, get_request()
returns ERR_PTR(-EAGAIN) if the queue is dying and the REQ_NOWAIT
flag has been passed to get_request(). Avoid that the kernel
reports soft lockup complaints in this case due to continuous
requeuing activity.

Fixes: 7083abbbf ("dm mpath: avoid that path removal can trigger an infinite loop")
Cc: stable@vger.kernel.org
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
drivers/md/dm-mpath.c

index 3486c829fa50ad661bce80dd8380cd6343c7cb18..d24e4b05f5dacefe5c0528b0ff3b75444bb216e6 100644 (file)
@@ -504,7 +504,6 @@ static int multipath_clone_and_map(struct dm_target *ti, struct request *rq,
                if (queue_dying) {
                        atomic_inc(&m->pg_init_in_progress);
                        activate_or_offline_path(pgpath);
-                       return DM_MAPIO_REQUEUE;
                }
                return DM_MAPIO_DELAY_REQUEUE;
        }