From: Hans-Joachim Picht <hpicht@redhat.com>
Date: Fri, 4 Apr 2008 19:51:55 +0200
Subject: [s390] qdio: change in timeout handling during establish
Message-id: 20080404175155.GG9759@redhat.com
O-Subject: [RHEL5 U3 PATCH 7/7] s390 - qdio: change in timeout handling during qdio establish
Bugzilla: 440421
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

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

If qdio establish runs in parallel with a channel error,
ccw_device_start_timeout may not trigger the
qdio_timeout_handler. In this case none of the states
ESTABLISHED nor ERROR is reached and the following
wait_event hangs forever.

The problem is fixed not making use of the timeout option with
ccw_device_start, but instead adding a timeout to the following
wait_event.

Bugzilla
=========

BZ 440421
https://bugzilla.redhat.com/show_bug.cgi?id=440421

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

This patch is submitted upstream: http://lkml.org/lkml/2008/2/9/83
I'll reply to this message as soon as we have a git commit id

Test status:
============
Kernel with patch was built and successfully tested

Please ACK.

With best regards,

Hans

diff --git a/drivers/s390/cio/qdio.c b/drivers/s390/cio/qdio.c
index 9b95742..8cfb11c 100644
--- a/drivers/s390/cio/qdio.c
+++ b/drivers/s390/cio/qdio.c
@@ -3183,13 +3183,11 @@ qdio_establish(struct qdio_initialize *init_data)
 	spin_lock_irqsave(get_ccwdev_lock(cdev),saveflags);
 
 	ccw_device_set_options(cdev, 0);
-	result=ccw_device_start_timeout(cdev,&irq_ptr->ccw,
-					QDIO_DOING_ESTABLISH,0, 0,
-					QDIO_ESTABLISH_TIMEOUT);
+	result = ccw_device_start(cdev, &irq_ptr->ccw,
+				QDIO_DOING_ESTABLISH, 0, 0);
 	if (result) {
-		result2=ccw_device_start_timeout(cdev,&irq_ptr->ccw,
-						 QDIO_DOING_ESTABLISH,0,0,
-						 QDIO_ESTABLISH_TIMEOUT);
+		result2 = ccw_device_start(cdev, &irq_ptr->ccw,
+					QDIO_DOING_ESTABLISH, 0, 0);
 		sprintf(dbf_text,"eq:io%4x",result);
 		QDIO_DBF_TEXT2(1,setup,dbf_text);
 		if (result2) {
@@ -3214,9 +3212,10 @@ qdio_establish(struct qdio_initialize *init_data)
 	}
 	
 	/* Timeout is cared for already by using ccw_device_start_timeout(). */
-	wait_event_interruptible(cdev->private->wait_q,
-		 irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
-		 irq_ptr->state == QDIO_IRQ_STATE_ERR);
+	wait_event_interruptible_timeout(cdev->private->wait_q,
+		irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
+		irq_ptr->state == QDIO_IRQ_STATE_ERR,
+		QDIO_ESTABLISH_TIMEOUT);
 
 	if (irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED)
 		result = 0;