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 73D76C7EE26 for ; Mon, 22 May 2023 18:20:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232791AbjEVSUo (ORCPT ); Mon, 22 May 2023 14:20:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229600AbjEVSUm (ORCPT ); Mon, 22 May 2023 14:20:42 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D338AF; Mon, 22 May 2023 11:20:41 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id d2e1a72fcca58-64d5f65a2f7so1244819b3a.1; Mon, 22 May 2023 11:20:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684779640; x=1687371640; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=XnNGFZ0Re+VRM8UtKCafqqilhh7RIrL5HAPnivOKzbI=; b=NzXyvxl+eSVn+61YhwsdEeeNs478YJ8xN7PSMdxpV/6VzBVVkU5kVSD7zG8Fx3GUnk Z/S4gARmV2kF5gle3UQBkay0WkXphb/SEIJLZGfdhADHFZrv0H9PKv7g3ANWTgJMV2fC AoYExvL/IbYRXK9A57srnMouw5q+tRoI8Wy8kQXbwQvXbNyaZ6w6FSaguMNkNR5KYKSn lOY6/pTuZI8CepbFHsrDCCCM/+agpMkLpPx/3V410dUCYzaXywb7lJf0VtbyKS3aiv1f TtezOHLHlOM/l8thVbZ+r6frmx49L4kplWhlcqckI9Zv3+WkpB1z9eXaJFgF3qKVXbQq GZGg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684779640; x=1687371640; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=XnNGFZ0Re+VRM8UtKCafqqilhh7RIrL5HAPnivOKzbI=; b=fIivPwJP4PwT2F5RqhA5zknsv/qH0QtDeYuju3ep5nMrolBnzPdz1t60dF8dX1kCIh 2rt8qztb3KiGX5sbUQ8FLj8s2OaiRXsNL0OXvasRNS9fvu9SMBYOhEI6ewUu+Nj3dFM1 QX5KcKsyVxmKUBvB7/H2BWrZGCSVrNqSCnEHlbvMgIj78Oe3BhBbmZVlHKC0h6HMV3nh Si8s3zLRWDnMLX+CfQSFKjirmX1koc+vMfhNs9KstvMvBUsP4qQvt7y6SEb6HfGXp6ff FjFJ3LboElqNvOn03jf3MP+IUevRDG3bbrIzDWv29jRm7nV8MWrAkujXA7xOnlfvVq1I HfnA== X-Gm-Message-State: AC+VfDyOOC5RegLCTXr4Dg39sSuQLoZWphHgdhi7fA3xonj4pfC19tGb f6L7yAQ2SCzzwWZlpCcP56c= X-Google-Smtp-Source: ACHHUZ5nvxuqc3Qq3LnGN+5GzCCr7OSBADk3L3tCN0e3vaf0VPR0/EU0cWZoEqwUS/0dHhFUDYP3mQ== X-Received: by 2002:a05:6a00:140b:b0:63d:3339:e967 with SMTP id l11-20020a056a00140b00b0063d3339e967mr14978767pfu.19.1684779640307; Mon, 22 May 2023 11:20:40 -0700 (PDT) Received: from localhost ([2620:10d:c090:400::5:39c]) by smtp.gmail.com with ESMTPSA id 10-20020a63060a000000b00502fd70b0bdsm4721026pgg.52.2023.05.22.11.20.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 May 2023 11:20:39 -0700 (PDT) Sender: Tejun Heo Date: Mon, 22 May 2023 08:20:38 -1000 From: Tejun Heo To: Z qiang Cc: Naresh Kamboju , open list , Linux-Next Mailing List , lkft-triage@lists.linaro.org, clang-built-linux , Nathan Chancellor , Arnd Bergmann , Dan Carpenter , Nick Desaulniers , Anders Roxell Subject: Re: next: WARNING: CPU: 0 PID: 63 at kernel/workqueue.c:1999 worker_enter_idle+0xb2/0xc0 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, May 22, 2023 at 09:24:09PM +0800, Z qiang wrote: > diff --git a/kernel/workqueue.c b/kernel/workqueue.c > index 9c5c1cfa478f..f8d739fef311 100644 > --- a/kernel/workqueue.c > +++ b/kernel/workqueue.c > @@ -1060,10 +1060,9 @@ void wq_worker_running(struct task_struct *task) > * and leave with an unexpected pool->nr_running == 1 on the newly > unbound > * pool. Protect against such race. > */ > - preempt_disable(); > + local_irq_disable(); > if (!(worker->flags & WORKER_NOT_RUNNING)) > worker->pool->nr_running++; > - preempt_enable(); > > /* > * CPU intensive auto-detection cares about how long a work item > hogged > @@ -1072,6 +1071,7 @@ void wq_worker_running(struct task_struct *task) > worker->current_at = worker->task->se.sum_exec_runtime; > > worker->sleeping = 0; > + local_irq_enable(); > } Ah, yeah, this is correct. Now we're modifying nr_running from timer tick too, so if don't block irq, the timer tick can ruin the not-irq-protected read-write-modify nr_running update from wq_worker_running(). Naresh, can you please confirm the fix? Thanks. -- tejun