From: Hans-Joachim Picht <hpicht@redhat.com>
Date: Tue, 20 May 2008 13:49:17 +0200
Subject: [s390] zfcp: fix check for handles in abort handler
Message-id: 20080520114917.GI16866@redhat.com
O-Subject: [RHEL5 U3 PATCH 4/4] s390 - zfcp: Fix check for handles in abort handler
Bugzilla: 447331
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

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

When an abort command is running in parallel to a port
or unit reopen, zfcp could escalate the ERP without
a reason.

The response to the abort request provides two handles
for a port or unit in the FSF status qualifier. The
ode that compares them was wrong.

Solution: Fix the comparison of the port or unit handles.

Bugzilla
=========

BZ 447331
https://bugzilla.redhat.com/show_bug.cgi?id=447331

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

The patch is included in linux-2.6 as git
commit id  8627533c115c546649693d68fed6a74762c47d51

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

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

Please ACK.

With best regards,

Hans

diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index a9507ef..be113ec 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -1129,8 +1129,8 @@ zfcp_fsf_abort_fcp_command_handler(struct zfcp_fsf_req *new_fsf_req)
 {
 	int retval = -EINVAL;
 	struct zfcp_unit *unit;
-	unsigned char status_qual =
-	    new_fsf_req->qtcb->header.fsf_status_qual.word[0];
+	union fsf_status_qual *fsf_stat_qual =
+		&new_fsf_req->qtcb->header.fsf_status_qual;
 
 	if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ERROR) {
 		/* do not set ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED */
@@ -1143,7 +1143,7 @@ zfcp_fsf_abort_fcp_command_handler(struct zfcp_fsf_req *new_fsf_req)
 	switch (new_fsf_req->qtcb->header.fsf_status) {
 
 	case FSF_PORT_HANDLE_NOT_VALID:
-		if (status_qual >> 4 != status_qual % 0xf) {
+		if (fsf_stat_qual->word[0] != fsf_stat_qual->word[1]) {
 			/*
 			 * In this case a command that was sent prior to a port
 			 * reopen was aborted (handles are different). This is
@@ -1169,8 +1169,7 @@ zfcp_fsf_abort_fcp_command_handler(struct zfcp_fsf_req *new_fsf_req)
 		break;
 
 	case FSF_LUN_HANDLE_NOT_VALID:
-		if (status_qual >> 4 != status_qual % 0xf) {
-			/* 2 */
+		if (fsf_stat_qual->word[0] != fsf_stat_qual->word[1]) {
 			/*
 			 * In this case a command that was sent prior to a unit
 			 * reopen was aborted (handles are different).