Received: by 2002:a05:6a10:9e8c:0:0:0:0 with SMTP id y12csp1132411pxx; Fri, 30 Oct 2020 02:58:13 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwwuiF6INqTDkPUd3aj65Mg65zXpe8lIvlZvO6bV4ikzeq/iIXWerSr6n8Iip2Zgkc7A1od X-Received: by 2002:a17:906:6a57:: with SMTP id n23mr1659811ejs.315.1604051893523; Fri, 30 Oct 2020 02:58:13 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1604051893; cv=none; d=google.com; s=arc-20160816; b=dBqyu1/f66LQ2By4etdT3X29alkr1va5a/dgaIkEdsx7qi7PiWT9l7264nK7vodFtP EzVhTgxrj42fcH83LsBxqg5aU39T/7z5lAWlGTk6q1d1T5WnkHtCdkYnOH/xjLfl7ArT IhOEvRSvRJS87K6zNgZWfuSq3CMeQetQ1xJk8ZWazS0gu3jGRsM/T4B3JJLYwbmqpA1R dNFWRd/OoU5tDNTjgY1nhe6WkKgzKR1WULzOCyX/SbUDonzsbG+jOOHtFZeRBooXBVTv OKFefdWpGBOWtnBYsBH1IN7bjFav7XmaRNuwEk9PDQRCLR7qvQ39dRum4Fcto7g8CwhJ rowA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=qtz8Xdgy6c70WedOeRlARJGaO0g6QyAZ2rh9hmruGO4=; b=PwqkZJMHtCvfwu4peLTTzlrwp7zTO3byc7aa+Z+MWnGCA6QhZvvFqiglT72i14eAqe CuSV5o7MBlrunB4+2ZveKZYlUnC6ZoZdEq1ZZ9Wj65i25NWC/oUhes7s+1/sOntl2lV1 X1r8hmoy3ezFnt1d/0JvnOWcLeCVOK/OIb9eO+zdjIdoN3PswLF2C/TR1o90yIATIoTo MZnhqHpFiSYuD558A7c+9oEtYIwIXqE79fTc0YNJngUYamqFQvYIeRxYuELZluAlNSRT yi4ah+Oo9gBqe5f5gE+gE0aeG08yc91EILr7yJ4OloxQmP4WJJooEwCpA9iLIjm6wy/U vkkA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=merlin.20170209 header.b=UDlYvcPU; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id v10si3984548edw.363.2020.10.30.02.57.50; Fri, 30 Oct 2020 02:58:13 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=merlin.20170209 header.b=UDlYvcPU; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726118AbgJ3J4G (ORCPT + 99 others); Fri, 30 Oct 2020 05:56:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725355AbgJ3J4G (ORCPT ); Fri, 30 Oct 2020 05:56:06 -0400 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13062C0613CF; Fri, 30 Oct 2020 02:56:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; 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=qtz8Xdgy6c70WedOeRlARJGaO0g6QyAZ2rh9hmruGO4=; b=UDlYvcPUqyS+VYfBYR/W9yycJn r14d/1xIMpRnIpiwiYr6C0aulO4DoR7t2uQovdcG7PmkvD2b711DZd5ipIuNgLOT+wzBlM3qiHzYa Yk8B7sffT6IjsQU2//8KkNfQWyYj/J6uOsl4vgedTPMjRwMiHINitI7qhnpt9WW3BuzUmJpDtX9C9 Y1JPiazNrVkgL0+BKMeTCpzXo2JfFrEF5jmrIaCiA89HuHnCeDm9I27MU2gM99Mc2btxg08MaueAx mfUTfFtOKzB7tL37pkxb+f8eCDpdK3MFd0xPnZBeDDFEW+4ims/j8a9iIRMmNT3DIOTSxysRJehXB KmX3dxxg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYR8Y-0005wo-HD; Fri, 30 Oct 2020 09:55:58 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 8232D3012C3; Fri, 30 Oct 2020 10:55:54 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 3E721203C534D; Fri, 30 Oct 2020 10:55:54 +0100 (CET) Date: Fri, 30 Oct 2020 10:55:54 +0100 From: Peter Zijlstra To: Boqun Feng Cc: Chris Wilson , linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org, tip-bot2 for Peter Zijlstra , Qian Cai , x86 Subject: Re: [tip: locking/core] lockdep: Fix usage_traceoverflow Message-ID: <20201030095554.GL2651@hirez.programming.kicks-ass.net> References: <20201027115955.GA2611@hirez.programming.kicks-ass.net> <20201027123056.GE2651@hirez.programming.kicks-ass.net> <160380535006.10461.1259632375207276085@build.alporthouse.com> <20201027154533.GB2611@hirez.programming.kicks-ass.net> <160381649396.10461.15013696719989662769@build.alporthouse.com> <160390684819.31966.12048967113267928793@build.alporthouse.com> <20201028194208.GF2628@hirez.programming.kicks-ass.net> <20201028195910.GI2651@hirez.programming.kicks-ass.net> <20201030035118.GB855403@boqun-archlinux> <20201030093806.GA2628@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201030093806.GA2628@hirez.programming.kicks-ass.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 30, 2020 at 10:38:06AM +0100, Peter Zijlstra wrote: > > if (!chain_head && ret != 2) { > > if (!check_prevs_add(curr, hlock)) > > I'm not entirely sure that doesn't still trigger the problem. Consider > @chain_head := true. Urgh, clearly my brain really isn't working well. Ignore that.