From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751337AbeC3FnV (ORCPT ); Fri, 30 Mar 2018 01:43:21 -0400 Received: from eahe.aehallh.com ([50.116.20.20]:36008 "EHLO eahe.aehallh.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751248AbeC3FnT (ORCPT ); Fri, 30 Mar 2018 01:43:19 -0400 Subject: Re: General protection fault with use_blk_mq=1. From: "Zephaniah E. Loss-Cutler-Hull" To: Paolo Valente , Jens Axboe Cc: "Zephaniah E. Loss-Cutler-Hull" , Linux Kernel Mailing List , linux-block , linux-scsi@vger.kernel.org References: <7d8a9c62-7d3e-879c-5b5b-30707f04553e@aehallh.com> <735c5d75-eacf-8ed2-ba9b-9ff4b0b5290d@kernel.dk> <882A26D2-BEB8-4CE3-B132-0DE31BFD5D28@linaro.org> <0a96375b-5a2e-e828-fa1f-a14af192be4c@aehallh.com> Message-ID: Date: Thu, 29 Mar 2018 22:43:16 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <0a96375b-5a2e-e828-fa1f-a14af192be4c@aehallh.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/29/2018 02:12 AM, Zephaniah E. Loss-Cutler-Hull wrote: > On 03/28/2018 10:13 PM, Paolo Valente wrote: >> In addition, the outcome of your attempt without >> CONFIG_DEBUG_BLK_CGROUP would give us useful bisection information: >> - if no failure occurs, then the issue is likely to be confined in >> that debugging code (which, on the bright side, is likely to be of >> occasional interest, for only a handful of developers) >> - if the issue still shows up, then we may have new hints on this odd >> failure >> >> Finally, consider that this issue has been reported to disappear from >> 4.16 [1], and, as a plus, that the service quality of BFQ had a >> further boost exactly from 4.16. > > I look forward to that either way then. >> >> Looking forward to your feedback, in case you try BFQ without >> CONFIG_DEBUG_BLK_CGROUP, > > I'm running that now, judging from the past if it survives until > tomorrow evening then we're good, so I should hopefully know in the next > day. Alright, I now have an uptime of over 20 hours, with scsi_mod.use_blk_mq=1 dm_mod.use_blk_mq=1 I did upgrade from 4.15.13 to 4.15.14 in the process, but a quick look at the changes doesn't have anything jump out at me as impacting this. So I'm reasonably comfortable stating that disabling CONFIG_DEBUG_BLK_CGROUP was sufficient to render this stable. Regards, Zephaniah E. Loss-Cutler-Hull.