From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8706DC433F5 for ; Fri, 10 Dec 2021 07:31:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235091AbhLJHeo (ORCPT ); Fri, 10 Dec 2021 02:34:44 -0500 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:60637 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230506AbhLJHeo (ORCPT ); Fri, 10 Dec 2021 02:34:44 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R561e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=haoxu@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0V-80-gZ_1639121467; Received: from 30.226.12.31(mailfrom:haoxu@linux.alibaba.com fp:SMTPD_---0V-80-gZ_1639121467) by smtp.aliyun-inc.com(127.0.0.1); Fri, 10 Dec 2021 15:31:07 +0800 Subject: Re: [PATCH v2 2/2] io_uring: ensure task_work gets run as part of cancelations To: Jens Axboe , io-uring@vger.kernel.org Cc: syzbot+21e6887c0be14181206d@syzkaller.appspotmail.com, stable@vger.kernel.org References: <20211209155956.383317-1-axboe@kernel.dk> <20211209155956.383317-3-axboe@kernel.dk> <89990fca-63d3-cbac-85cc-bce2818dd30e@kernel.dk> <227847a6-a76c-3942-a563-7d492b0d2ced@linux.alibaba.com> From: Hao Xu Message-ID: <281d4248-676e-efc5-d95a-d848cbf0df41@linux.alibaba.com> Date: Fri, 10 Dec 2021 15:31:06 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org 在 2021/12/10 下午12:22, Jens Axboe 写道: > On 12/9/21 8:29 PM, Hao Xu wrote: >> 在 2021/12/10 上午12:16, Jens Axboe 写道: >>> If we successfully cancel a work item but that work item needs to be >>> processed through task_work, then we can be sleeping uninterruptibly >>> in io_uring_cancel_generic() and never process it. Hence we don't >>> make forward progress and we end up with an uninterruptible sleep >>> warning. >>> >>> Add the waitqueue earlier to ensure that any wakeups from cancelations >>> are seen, and switch to using uninterruptible sleep so that postponed >> ^ typo > Not really a typo, but should be killed from v2 for sure. I'll do that. > Don't know why the ^ char doesn't align with 'uninterruptible' ... here I mean 'uninterruptible' is a typo