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=-5.8 required=3.0 tests=BAYES_00,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 44BB2C4320A for ; Mon, 30 Aug 2021 21:29:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 233F660E77 for ; Mon, 30 Aug 2021 21:29:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237514AbhH3VaA (ORCPT ); Mon, 30 Aug 2021 17:30:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232907AbhH3V36 (ORCPT ); Mon, 30 Aug 2021 17:29:58 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E586C061575; Mon, 30 Aug 2021 14:29:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=g2gXss1DJ1JAJXF0vbtWUIqxsGH+dUvV29MGmlrRUss=; b=HIgSQhBRENQDUeREEfmcXmB96a 2Nb3sW6HgKHcvb3FTItmfTew+9SRZh7p8azReltCbDPqRMvT23E36oakL43buiTboqrMMDM5l0lLm Hdg29kQZGLVKMwvv4jolg19zQx0It9caZyBdhabBtTvXDvNFgMewo3YLRddUm+cB4OOt47JMAfOf4 TFa4VFGXcZ1ZgrN6omDS47CvUYC+2wSY4wnGdvsJZFyHVmoOZYt/dwtgnG5U72ohBS9XTeRryGI2J CFMXz6CNF49EtL/oEHBNsgvlpZbLuKemV0MxWPCaXSGGcnkmosc5S+gdTBJ/pzVxXlBt6wTuYE0DJ C72O5J9w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mKops-00EVqS-0J; Mon, 30 Aug 2021 21:28:56 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D7078300103; Mon, 30 Aug 2021 23:28:54 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id BC84A2D3EECF8; Mon, 30 Aug 2021 23:28:54 +0200 (CEST) Date: Mon, 30 Aug 2021 23:28:54 +0200 From: Peter Zijlstra To: Linus Torvalds Cc: Guenter Roeck , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Linux Kernel Mailing List , linux-s390 , Sven Schnelle Subject: Re: Linux 5.14 Message-ID: References: <20210830201225.GA2671970@roeck-us.net> 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 On Mon, Aug 30, 2021 at 01:15:37PM -0700, Linus Torvalds wrote: > On Mon, Aug 30, 2021 at 1:12 PM Guenter Roeck wrote: > > > > So far so good, but there is a brand new runtime warning, seen when booting > > s390 images. > > > > [ 3.218816] ------------[ cut here ]------------ > > [ 3.219010] WARNING: CPU: 1 PID: 0 at kernel/sched/core.c:5779 sched_core_cpu_starting+0x172/0x180 > > [ 3.222845] Call Trace: > > [ 3.222992] [<0000000000186e86>] sched_core_cpu_starting+0x176/0x180 > > [ 3.223114] ([<0000000000186dc4>] sched_core_cpu_starting+0xb4/0x180) > > [ 3.223182] [<00000000001963e4>] sched_cpu_starting+0x2c/0x68 > > [ 3.223243] [<000000000014f288>] cpuhp_invoke_callback+0x318/0x970 > > [ 3.223304] [<000000000014f970>] cpuhp_invoke_callback_range+0x90/0x108 > > [ 3.223364] [<000000000015123c>] notify_cpu_starting+0x84/0xa8 > > [ 3.223426] [<0000000000117bca>] smp_init_secondary+0x72/0xf0 > > [ 3.223492] [<0000000000117846>] smp_start_secondary+0x86/0x90 > > > > Commit 3c474b3239f12 ("sched: Fix Core-wide rq->lock for uninitialized > > CPUs") seems to be the culprit. Indeed, the warning is gone after reverting > > this commit. > > Ouch, not great timing. > > Adding the s390 people to the cc too, just to make sure everybody > involved is aware. 'Funny' thing, Sven actually tested that on s390. I had already comitted the patch which is why his tag isn't on the commit: https://lkml.kernel.org/r/yt9dy28o8q0o.fsf@linux.ibm.com Anyway, looks like Thomas found something fishy in their topology code. Lemme go catch up.