From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-f196.google.com ([209.85.214.196]:38979 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728856AbfHBC40 (ORCPT ); Thu, 1 Aug 2019 22:56:26 -0400 Received: by mail-pl1-f196.google.com with SMTP id b7so33087394pls.6 for ; Thu, 01 Aug 2019 19:56:26 -0700 (PDT) Subject: Re: [PATCH 1/1] s390/dasd: fix endless loop after read unit address configuration References: <20190801110630.82432-1-sth@linux.ibm.com> <20190801110630.82432-2-sth@linux.ibm.com> From: Jens Axboe Message-ID: <20c4971d-68cd-b4d0-fb40-deef771602b1@kernel.dk> Date: Thu, 1 Aug 2019 20:47:51 -0600 MIME-Version: 1.0 In-Reply-To: <20190801110630.82432-2-sth@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Stefan Haberland Cc: linux-block@vger.kernel.org, linux-s390@vger.kernel.org, hoeppner@linux.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, gor@linux.ibm.com On 8/1/19 5:06 AM, Stefan Haberland wrote: > After getting a storage server event that causes the DASD device driver > to update its unit address configuration during a device shutdown there is > the possibility of an endless loop in the device driver. > > In the system log there will be ongoing DASD error messages with RC: -19. > > The reason is that the loop starting the ruac request only terminates when > the retry counter is decreased to 0. But in the sleep_on function there are > early exit paths that do not decrease the retry counter. > > Prevent an endless loop by handling those cases separately. > > Remove the unnecessary do..while loop since the sleep_on function takes > care of retries by itself. Applied for 5.3, thanks. -- Jens Axboe