From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH 0/2] sd: Fix a deadlock between event checking and device removal Date: Sat, 12 Nov 2016 21:47:08 -0800 Message-ID: <1479016028.17624.16.camel@linux.vnet.ibm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:45714 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751481AbcKMFrO (ORCPT ); Sun, 13 Nov 2016 00:47:14 -0500 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uAD5hYMM144217 for ; Sun, 13 Nov 2016 00:47:13 -0500 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0a-001b2d01.pphosted.com with ESMTP id 26ny91e6uq-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Sun, 13 Nov 2016 00:47:13 -0500 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 13 Nov 2016 00:47:12 -0500 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Bart Van Assche , "Martin K. Petersen" Cc: Mike Snitzer , Hannes Reinecke , "linux-scsi@vger.kernel.org" On Fri, 2016-11-11 at 16:38 -0800, Bart Van Assche wrote: > Hello James and Martin, > > This short patch series fixes a deadlock that I ran into for the > first time several months ago but for which I had not yet had the > time to post a fix. As usual, feedback is appreciated. First question would be why do we need to push highly dm specific knowledge into block, like REQ_FAIL_IF_NO_PATH. Can't we just use REQ_FAILFAST_X for this? Also, I don't quite understand how you've configured multipath underneath SCSI. I thought dm-mp always went on top? James