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 X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5071DC4338F for ; Wed, 28 Jul 2021 17:45:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3460061050 for ; Wed, 28 Jul 2021 17:45:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229603AbhG1Rpv (ORCPT ); Wed, 28 Jul 2021 13:45:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:34086 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229556AbhG1Rpv (ORCPT ); Wed, 28 Jul 2021 13:45:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C371E6023F; Wed, 28 Jul 2021 17:45:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1627494349; bh=F2v66I70HoIjFP9RyBBXTn+x6D05McIv+z/aLBTToqg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iLtcfzbNIOvRLDbL+QfRmgdZPmuoKtDK7qFKUAcXww73qsgDaX6itGP30MFKRWxCy 8Yn555T4ez+5i79sRRymlmViFfwYaIQ25qoPYOWrgJaoCZa282V+rtCc8OF3OTTEix 8OpR7Bgvpl31381yxJ5guwWEZPp0iekvvXMS/Opc= Date: Wed, 28 Jul 2021 19:45:46 +0200 From: Greg KH To: bof@bof.de Cc: stable@vger.kernel.org, regressions@lists.linux.dev Subject: Re: stable 5.4.135 REGRESSION / once-a-day WARNING: at kthread_is_per_cpu+0x1c/0x20 Message-ID: References: <61018d93.xsvXcO161PFLQFCX%bof@bof.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <61018d93.xsvXcO161PFLQFCX%bof@bof.de> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Jul 28, 2021 at 07:02:11PM +0200, bof@bof.de wrote: > Hi, > > first regression report in a long while... hope I'm doing this right. > > I run self-build, from time to time, mainline kernels, in production, both on HP DL hosts + inside kvm VMs on these. I usually stick to a certain > long term stable line for a year or three. As such, for a bit longer already, I'm running 5.4, starting somewhere at 5.4.4x. At the moment, I started > to roll out 5.4.135 on a few of the hosts, and encounter a rare "WARNING: CPU ... PID ... at kthread_is_per_cpu+0x1c/0x20" splat (see full dmesg below) > > Previous kernel I was running there, never seeing that, was 5.4.114 > > Searching a bit, turns up this 5.4.118 commit / backport: > https://lore.kernel.org/stable/162074016514831@kroah.com/ > https://lore.kernel.org/lkml/20210407220628.3798191-2-valentin.schneider@arm.com/ > pointing to exactly the place shown in the dmesg trace. Can you narrow this down to a specific commit using 'git bisect'? thanks, greg k-h