[SCSI] zfcp: fix deadlock caused by shared work queue tasks

Each adapter reopen trigger automatically a scan_port task which
is waiting for the ERP to be finished before further processing.
Since the initial device setup enqueues adapter, port and LUN which
are individual ERP actions, this process would start after
everything is done. Unfortunately the port_reopen requires another
scheduled work to be finished which is queued after the automatic
scan_port -> deadlock !

This fix creates an own work queue for ERP based nameserver requests.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index 7fa8937c8c58..73eb41580f25 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -602,6 +602,7 @@ struct zfcp_data {
         struct kmem_cache       *fsf_req_qtcb_cache;
         struct kmem_cache       *sr_buffer_cache;
         struct kmem_cache       *gid_pn_cache;
+        struct workqueue_struct *work_queue;
 };
 
 /* struct used by memory pools for fsf_requests */