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 29AB9C7EE29 for ; Mon, 22 May 2023 21:12:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229803AbjEVVMN (ORCPT ); Mon, 22 May 2023 17:12:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229505AbjEVVMK (ORCPT ); Mon, 22 May 2023 17:12:10 -0400 Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0597A9C; Mon, 22 May 2023 14:12:10 -0700 (PDT) Received: by mail-pg1-x530.google.com with SMTP id 41be03b00d2f7-517c840f181so3539719a12.3; Mon, 22 May 2023 14:12:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684789929; x=1687381929; 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=+XNhMRDIcd5RhQtvp0YIKYqZLNH6+pbXq+kWmpBSynM=; b=k1K1HyzvnqnBe8r2Rpb2ATAXebNjQ+9Bj004eYb67TIX3qkCYFzgQYrfbfof/qs3fV E3bOOixQ4DIcMdIMfzpQ4RfAjXDQoDqAOGWrbfUxf2/ZNc+KM0OYHZ9lU2A+SK8usHdg dc/ZvHPzmHRsXxUFogSaI7+kAzu1XXJiiGb5QhVJAxWHDSGYx4O/aRabFYIT9yYBpg0S oDgmbR7SKYkH53aRuo/PUAuGIz7l4rya+8MXmoqmBJbDcvBs40ChsEt9FeVe2iBICoBa Dvl/vll4zbsfzri82BmGt63uVS0Ge5oAnStn/7nZqW4C8ZRrmMwWkd/j5S4GA/kkWEc7 iHgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684789929; x=1687381929; 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=+XNhMRDIcd5RhQtvp0YIKYqZLNH6+pbXq+kWmpBSynM=; b=LrPKcO6TZT8ziB/0SSh8hFN//5qdAqtfgE+lDarjwKro80W1dTtEjBNEwIHYF9t+Bw ktGUdGXY78AUjMeRoBhZoMBPWQfZg5Q1rXcrjEZi4nwo2nya7O8WtkBFxy7IZHAoAV6e PWpfhBH/hgwj6WcxFe8/R4zTskGhOh4hL3jlM7/7ANDi/NkzBhdX35NvBk6ezr5peMGb IYXGnVJGrBwFoBksOAqPZCTAlWOvcubELFkd7Wd05qbjGCfR8HSMTj/LG2BPkS1s8fM2 q9dI3gSKwXGclveKTE8HucGYvX3Zgwt3fWojLuDOOHFWpxiJ/f9t/EQR2LItqN9T/fje AYiA== X-Gm-Message-State: AC+VfDwvr0So5/DyW8CAgSUTPDYibwAVUD7cQMOWqTACLUFZwS4+IJ9P iN5DR1ZGjKTVkLercSGq5Gg= X-Google-Smtp-Source: ACHHUZ60CLOp7DtHkbt5u0VTx8QiCC05myGgdTMUzzuhOr29K4CA9z9bUTYJaQhqyLyPqXt0bMuqYA== X-Received: by 2002:a05:6a20:7295:b0:103:ef39:a832 with SMTP id o21-20020a056a20729500b00103ef39a832mr12188478pzk.23.1684789929229; Mon, 22 May 2023 14:12:09 -0700 (PDT) Received: from localhost ([2620:10d:c090:400::5:39c]) by smtp.gmail.com with ESMTPSA id lt11-20020a17090b354b00b0024df400a9e6sm4556611pjb.37.2023.05.22.14.12.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 May 2023 14:12:08 -0700 (PDT) Sender: Tejun Heo Date: Mon, 22 May 2023 11:12:07 -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-next@vger.kernel.org On Mon, May 22, 2023 at 08:20:38AM -1000, Tejun Heo wrote: > 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? Z qiang, while waiting for Naresh's test result, can you send the fix as a proper signed-off-patch? Thanks. -- tejun