From: Hans-Joachim Picht <hpicht@redhat.com>
Date: Wed, 22 Oct 2008 14:17:20 +0200
Subject: [s390] cio: DASD device driver times out
Message-id: 20081022121720.GB26181@redhat.com
O-Subject: [RHEL5 U4 PATCH 2/5] s390 - cio: DASD device driver times out
Bugzilla: 459803
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

Description
============

The DASD device driver times out even if processing is completed.
When the status of a device is changed intentionally, there is the
option to first let the ongoing i/o processing come to an end
rather then just to stop it. To do so, the device is set to state
wait4io. But after completion of the i/o processing the device
remains in that state, wrongly indicating that there are still
outstanding interrupts.

Solution: Trigger a path verification for the device in state wait4io after
completion of the i/o processing so that the device is set to a
proper state.

Bugzilla
=========

BZ 459803
https://bugzilla.redhat.com/show_bug.cgi?id=459803

Upstream status of the patch:
=============================

The upstream codebase is not affected by this problem.
Therefor the patch hasn't been posted upstream.

Test status:
============

The patch has been tested and fixes the problem.
The fix has been verified by the IBM test department.

Please ACK.

With best regards,

	--Hans

diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index b2f590e..162154f 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -1032,7 +1032,6 @@ static void
 ccw_device_wait4io_irq(struct ccw_device *cdev, enum dev_event dev_event)
 {
 	struct irb *irb;
-	struct subchannel *sch;
 
 	irb = (struct irb *) __LC_IRB;
 	/*
@@ -1046,18 +1045,12 @@ ccw_device_wait4io_irq(struct ccw_device *cdev, enum dev_event dev_event)
 		}
 		return;
 	}
-
-	/* Iff device is idle, reset timeout. */
-	sch = to_subchannel(cdev->dev.parent);
-	if (!stsch(sch->schid, &sch->schib)) {
-		if (sch->schib.scsw.actl == 0) {
-			ccw_device_set_timeout(cdev, 0);
-			/* Start delayed path verification. */
-			ccw_device_online_verify(cdev, 0);
-		}
-	}
 	/* Call the handler. */
-	ccw_device_call_handler(cdev);
+	if (ccw_device_call_handler(cdev)) {
+		ccw_device_set_timeout(cdev, 0);
+		/* Start delayed path verification. */
+		ccw_device_online_verify(cdev, 0);
+	}
 }
 
 static void