Received: by 2002:ac0:a5a7:0:0:0:0:0 with SMTP id m36-v6csp918271imm; Fri, 17 Aug 2018 08:46:00 -0700 (PDT) X-Google-Smtp-Source: AA+uWPzDZGNA10t5N4zWCzxuU0ZWnehD81YSE068VS7mYrBn/sgwnpGTODFBr7bC5DvfbE/nVsEP X-Received: by 2002:a62:d544:: with SMTP id d65-v6mr36859733pfg.107.1534520760795; Fri, 17 Aug 2018 08:46:00 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1534520760; cv=none; d=google.com; s=arc-20160816; b=RaanjYslUHO3RYTiHivvhUsZiN6iLuhq7evXQd/83IEzY2muNIbkvFh01MI5bSRLCI fwL3usUDtMcIyrzM6xlp7YUzfSq98/sghmf0Yt0ktVfYQvq5+Y2Qn24piHj9inCEEVyR xL/1dpYjwilziyGbIJ33kuXmFrl2DjYQfisigPqxfOKPVc+Ii0PAjVvZ7Fo0RUpCJIAI DzFDqbyjneAIXit5FBmN2+lsfqDKfb948U51fqc4x4+eybsIo1YhzuvVYGcpypS53ONN FYeGSAT+P+9e1NjOSYLVOiDoUHP1LDvezzkuvRKa1704D1dArg+vkiXWiM6l4+flhPMo 7vtQ== 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:dkim-signature:arc-authentication-results; bh=FNceucLDzp77F4Kl4M3acLkCV+jFAwmtV2jOYU9AXss=; b=bcxeSpSzVIdwZBW6DBu9+eF0Cg+rPF5PDr8gkRumo3qS86M1hoLmaLHnR0HRDEUiW0 N/APqXeK3H2oFy7uA2AySKcgx5kujpisrZZLDtFWhqXseUQV7JbJY3Nq7Y6nAdSDICaT kW+6SOq0UTXBZAqZMbfSXO9H+v85+6adIT5o4u59zskhuasklq+tpf0BKfDvBBL/lwDV OFkA+VUYOzEq/RgRAu3sj5WMSgff3lwp98aSu13OVDevkUXdYjIu30b8QwMnZxtbx2XW /qv4iVpQQQmN3KuDF4z1xgNY8MTdbxtVdIuU6wIiSwyQPSWNfKw41Mc3XugSDpKp1AP7 IoLg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=rpDVdHiW; 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; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id i126-v6si2414479pgd.332.2018.08.17.08.45.45; Fri, 17 Aug 2018 08:46:00 -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; dkim=pass header.i=@kernel.org header.s=default header.b=rpDVdHiW; 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; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727745AbeHQSsY (ORCPT + 99 others); Fri, 17 Aug 2018 14:48:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:39002 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727398AbeHQSsY (ORCPT ); Fri, 17 Aug 2018 14:48:24 -0400 Received: from localhost (unknown [69.71.4.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BC415208A6; Fri, 17 Aug 2018 15:44:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1534520673; bh=FNceucLDzp77F4Kl4M3acLkCV+jFAwmtV2jOYU9AXss=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rpDVdHiW7UU0+2kXuNYTN74JzSXhzDJwAEjolwIORrkUISn7VA19NxVXuLOEMb+Vp rN3JmJYPnT+ggTXHisz8iGdlyPtIhfihgNbrFwzsrMdKIrxd11Za9jWdm6pNGuEpNK +sBNq6ZP/Wes7DMoVzEOPPs7IWmOseiyGjqlSSl0= Date: Fri, 17 Aug 2018 10:44:31 -0500 From: Bjorn Helgaas To: Benjamin Herrenschmidt Cc: linux-pci@vger.kernel.org, Hari Vyas , Ray Jui , Srinath Mannam , Guenter Roeck , Jens Axboe , Lukas Wunner , Konstantin Khlebnikov , Marta Rybczynska , Pierre-Yves Kerbrat , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 1/6] Revert "PCI: Fix is_added/is_busmaster race condition" Message-ID: <20180817154431.GC128050@bhelgaas-glaptop.roam.corp.google.com> References: <20180817044902.31420-1-benh@kernel.crashing.org> <20180817044902.31420-2-benh@kernel.crashing.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180817044902.31420-2-benh@kernel.crashing.org> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 17, 2018 at 02:48:57PM +1000, Benjamin Herrenschmidt wrote: > This reverts commit 44bda4b7d26e9fffed6d7152d98a2e9edaeb2a76. Just to be clear, if I understand correctly, this is a pure revert of 44bda4b7d26e and as such it reintroduces the problem solved by that commit. If your solution turns out to be better, that's great, but it would be nice to avoid the bisection hole of reintroducing the problem, then fixing it again later. > The new pci state mutex provides a simpler way of addressing > this race and avoids the relative includes added to the powerpc > code.