Received: by 2002:a25:6193:0:0:0:0:0 with SMTP id v141csp4363884ybb; Tue, 7 Apr 2020 06:10:10 -0700 (PDT) X-Google-Smtp-Source: APiQypIHpD+V5DxYr9DR9cPAIE8t6FjPEkef0utPYyQnbao8kZp/7D1CPb4zKlyU3mQoOYG9cqtn X-Received: by 2002:aca:5191:: with SMTP id f139mr1637433oib.140.1586265010067; Tue, 07 Apr 2020 06:10:10 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1586265010; cv=none; d=google.com; s=arc-20160816; b=wHtMKxyZNoD8PAgofWKYbLZLykjiwcuFsgbuyOGP1NWoHprxkmwU8qWuTomx7jFSZx Mu8bNGOnpz8nKiVw87QizPS3GYLuIrnb3TuGaAjxeb7gXTF6txNUqmlTEg1ZdmC70GfJ QT3QsrrBFEYn2qI3/BE46/9ZdDaN0Nd1YgdiY5N56HakBaZntNoExhpMn/iuAq0yb8aa fVm2fb6gtPjz3u0OqXc/Y3kRN9lfRExG3cjjbfy9223h8LDqFMmo6VtmKx0Pj0mqtkR1 nmSgLiYcGj/bgaX/mS9sZ8cIZdukH8UOEzZ9q15dIg9UhLkWZ4fXZ62/rZ+xSNoF1bkQ sEyQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=Zo8YqpgITjLD9J5KMJAqaIqGRInz4xAcbZQXT0wvqJ0=; b=c8b43lSG7ErA0iACJVQj6SXTmuIKMY++9ve6NYe49mG3cRPhh/7jBLWf0z2thgY6lx RkYYXOyby26Dvh83Uvg45CsEDx1zPOkfcMlbG8OjCDWV60oChd8G3+Ptic4AKdbnSSAp LYLWbvtKRd/NV1aXSSJX9zogLTmERMvx7xNwF6STPZwS8Pr1jAjNt3BodLSY29VKtOXt AEuTt1aKEOLB1WmN86QQMjQgAlnOjfi1CgHcaLH7lWyAFU3E46c/ynM6BNjSoHTpwUPd IFdW0ndv22/OSI6eWycs3nazFrVnPbLzg6EuFxH5aH9R7bYJtTuBl5TMGRp4L6xzBpF4 weMA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id t11si619515oig.108.2020.04.07.06.09.52; Tue, 07 Apr 2020 06:10:10 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728831AbgDGNHa (ORCPT + 99 others); Tue, 7 Apr 2020 09:07:30 -0400 Received: from foss.arm.com ([217.140.110.172]:56134 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726562AbgDGNHa (ORCPT ); Tue, 7 Apr 2020 09:07:30 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BF0F031B; Tue, 7 Apr 2020 06:07:29 -0700 (PDT) Received: from e107158-lin.cambridge.arm.com (e107158-lin.cambridge.arm.com [10.1.195.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BDF043F68F; Tue, 7 Apr 2020 06:07:28 -0700 (PDT) Date: Tue, 7 Apr 2020 14:07:26 +0100 From: Qais Yousef To: Tejun Heo Cc: Qian Cai , Prateek Sood , Li Zefan , cgroups@vger.kernel.org, LKML , Peter Zijlstra Subject: Re: Deadlock due to "cpuset: Make cpuset hotplug synchronous" Message-ID: <20200407130725.jhtth3bneo33zex6@e107158-lin.cambridge.arm.com> References: <20200325191922.GM162390@mtj.duckdns.org> <20200326101529.xh763j5frq2r7mqv@e107158-lin> <20200403145523.GC162390@mtj.duckdns.org> <20200406105522.c66p4vzzzylety5d@e107158-lin.cambridge.arm.com> <20200406143405.GH162390@mtj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200406143405.GH162390@mtj.duckdns.org> User-Agent: NeoMutt/20171215 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/06/20 10:34, Tejun Heo wrote: > On Mon, Apr 06, 2020 at 11:55:23AM +0100, Qais Yousef wrote: > > What would be the right approach to get a fix in then? We have been skipping > > this test for a while and we'd like to enable it but this failure is a > > blocking issue. > > Update the test so that it accounts for the async nature of the operation? With a sleep() between the hp ops and the read? Isn't this a nasty hack? I was just trying to find out what can be done for 5.7. But based on your response this is sadly a dead end. For no reason I can comprehend. -- Qais Yousef