[S390] cio: fix unreg race in set_online path
Sebastian Ott [Mon, 23 May 2011 08:23:32 +0000 (10:23 +0200)]
In ccw_device_set_online we basically start path verification and
wait for the device to reach a final state. If it turns out that the
device has no useable path we schedule the deregistration of the
device (which is still in an non-final state) and wake up the waiting
process. The deregistration process will set a final state, but if
the wake up happens to be prior to this, the device will hang forever
in ccw_device_set_online.

To fix this just set the final NOT_OPER state prior to the scheduled
deregistration of the device.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/device_fsm.c

index 6084103..e087a86 100644 (file)
@@ -408,9 +408,10 @@ ccw_device_done(struct ccw_device *cdev, int state)
                CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
                              "%04x\n", cdev->private->dev_id.devno,
                              sch->schid.sch_no);
-               if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
+               if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
+                       cdev->private->state = DEV_STATE_NOT_OPER;
                        ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
-               else
+               } else
                        ccw_device_set_disconnected(cdev);
                cdev->private->flags.donotify = 0;
                break;