From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:63670 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727414AbgLQQCZ (ORCPT ); Thu, 17 Dec 2020 11:02:25 -0500 From: Stefan Haberland Subject: [PATCH 1/4] s390/dasd: fix hanging device offline processing Date: Thu, 17 Dec 2020 16:59:04 +0100 Message-Id: <20201217155907.36436-2-sth@linux.ibm.com> In-Reply-To: <20201217155907.36436-1-sth@linux.ibm.com> References: <20201217155907.36436-1-sth@linux.ibm.com> List-ID: To: Jens Axboe Cc: linux-block@vger.kernel.org, Jan Hoeppner , linux-s390@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Christian Borntraeger For an LCU update a read unit address configuration IO is required. This is started using sleep_on(), which has early exit paths in case the device is not usable for IO. For example when it is in offline processing. In those cases the LCU update should fail and not be retried. Therefore lcu_update_work checks if EOPNOTSUPP is returned or not. Commit 47825e05d93e ("s390/dasd: fix endless loop after read unit address configuration") accidentally removed the EOPNOTSUPP return code from read_unit_address_configuration(), which in turn might lead to an endless loop of the LCU update in offline processing. Fix by returning EOPNOTSUPP again if the device is not able to perform the request. Fixes: 47825e05d93e ("s390/dasd: fix endless loop after read unit address configuration") Cc: stable@vger.kernel.org #5.3 Signed-off-by: Stefan Haberland Reviewed-by: Jan Hoeppner --- drivers/s390/block/dasd_alias.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/s390/block/dasd_alias.c b/drivers/s390/block/dasd_alias.c index 99f86612f775..31e8b5d48e86 100644 --- a/drivers/s390/block/dasd_alias.c +++ b/drivers/s390/block/dasd_alias.c @@ -462,11 +462,19 @@ static int read_unit_address_configuration(struct dasd_device *device, spin_unlock_irqrestore(&lcu->lock, flags); rc = dasd_sleep_on(cqr); - if (rc && !suborder_not_supported(cqr)) { + if (!rc) + goto out; + + if (suborder_not_supported(cqr)) { + /* suborder not supported or device unusable for IO */ + rc = -EOPNOTSUPP; + } else { + /* IO failed but should be retried */ spin_lock_irqsave(&lcu->lock, flags); lcu->flags |= NEED_UAC_UPDATE; spin_unlock_irqrestore(&lcu->lock, flags); } +out: dasd_sfree_request(cqr, cqr->memdev); return rc; } -- 2.17.1