From: Hans-Joachim Picht <hpicht@redhat.com>
Date: Thu, 6 Nov 2008 15:40:46 +0100
Subject: [s390] qeth: avoid problems after failing recovery
Message-id: 20081106144046.GA12027@redhat.com
O-Subject: [RHEL5 U4 PATCH 1/4] s390 - qeth: avoid problems after failing recovery
Bugzilla: 468019
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

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

hsi recovery hang after z/VM CP detach/attach

Problem: IFF_UP flag is switched off/on during qeth recovery.
If recovery fails for some reason, a following
dev_close() is aborted due to the reset IFF_UP.
In case of a device unit check "command rejected"
the qeth driver tries to continue processing, but
following OSA-commands run into timeout causing
recovery to hang.

Solution:  Do not touch IFF_UP flag during qeth recovery,
but invoke dev_close() in case of failing recovery.
Cancel outstanding control commands in case of
Data Checks or Channel Checks.

Bugzilla
=========

BZ 468019
https://bugzilla.redhat.com/show_bug.cgi?id=468019

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

Patch is upstream in linux-2.6
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=28a7e4c906bd86419eb8572b3b1343e619cd1470

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/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index 9e201dc..791c771 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -370,7 +370,7 @@ qeth_get_problem(struct ccw_device *cdev, struct irb *irb)
 		if (sense[SENSE_COMMAND_REJECT_BYTE] &
 		    SENSE_COMMAND_REJECT_FLAG) {
 			QETH_DBF_TEXT(trace,2,"CMDREJi");
-			return 0;
+			return 1;
 		}
 		if ((sense[2] == 0xaf) && (sense[3] == 0xfe)) {
 			QETH_DBF_TEXT(trace,2,"AFFE");
@@ -455,6 +455,7 @@ qeth_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
 		}
 		rc = qeth_get_problem(cdev,irb);
 		if (rc) {
+			qeth_clear_ipacmd_list(card);
 			qeth_schedule_recovery(card);
 			goto out;
 		}
@@ -973,9 +974,13 @@ qeth_recover(void *ptr)
 	if (!rc)
 		PRINT_INFO("Device %s successfully recovered!\n",
 			   CARD_BUS_ID(card));
-	else
+	else {
+		rtnl_lock();
+		dev_close(card->dev);
+		rtnl_unlock();
 		PRINT_INFO("Device %s could not be recovered!\n",
 			   CARD_BUS_ID(card));
+	}
 	/* don't run another scheduled recovery */
 	qeth_clear_thread_start_bit(card, QETH_RECOVER_THREAD);
 	qeth_clear_thread_running_bit(card, QETH_RECOVER_THREAD);
@@ -3910,7 +3915,6 @@ qeth_open(struct net_device *dev)
 	}
 	card->data.state = CH_STATE_UP;
 	card->state = CARD_STATE_UP;
-	card->dev->flags |= IFF_UP;
 	netif_start_queue(dev);
 
 	if (!card->lan_online && netif_carrier_ok(dev))
@@ -3928,7 +3932,6 @@ qeth_stop(struct net_device *dev)
 	card = (struct qeth_card *) dev->priv;
 
 	netif_tx_disable(dev);
-	card->dev->flags &= ~IFF_UP;
 	if (card->state == CARD_STATE_UP)
 		card->state = CARD_STATE_SOFTSETUP;
 	return 0;