i2o: destroy event queue only when drv->event is set

i2o_driver_register() initalizes event queue for driver only when
drv->event is set.  So similarly the event queue should be destroyed only
when drv->event is set in the error path.  Otherwise destroy_workqueue()
will called with NULL.

Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/message/i2o/driver.c b/drivers/message/i2o/driver.c
index d3235f213c8..d330e4eb86a 100644
--- a/drivers/message/i2o/driver.c
+++ b/drivers/message/i2o/driver.c
@@ -123,8 +123,12 @@ int i2o_driver_register(struct i2o_driver *drv)
         }
 
         rc = driver_register(&drv->driver);
-        if (rc)
-                destroy_workqueue(drv->event_queue);
+        if (rc) {
+                if (drv->event) {
+                        destroy_workqueue(drv->event_queue);
+                        drv->event_queue = NULL;
+                }
+        }
 
         return rc;
 };