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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 C6982C32764 for ; Thu, 2 Jan 2020 02:35:14 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9C04921734 for ; Thu, 2 Jan 2020 02:35:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C04921734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 679A485EF9; Thu, 2 Jan 2020 02:35:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VWyOXorhMWm8; Thu, 2 Jan 2020 02:35:13 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id 990D685C19; Thu, 2 Jan 2020 02:35:13 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7CD24C18DC; Thu, 2 Jan 2020 02:35:13 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id EA423C077D for ; Thu, 2 Jan 2020 02:35:11 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id DBD6E85540 for ; Thu, 2 Jan 2020 02:35:11 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xXNJqUIzzjb2 for ; Thu, 2 Jan 2020 02:35:11 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 4819A84F2E for ; Thu, 2 Jan 2020 02:35:11 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 01 Jan 2020 18:35:11 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,385,1571727600"; d="scan'208";a="244494608" Received: from allen-box.sh.intel.com (HELO [10.239.159.136]) ([10.239.159.136]) by fmsmga004.fm.intel.com with ESMTP; 01 Jan 2020 18:35:10 -0800 Subject: Re: [PATCH 22/22] iommu/vt-d: Add a quirk flag for scope mismatched devices To: Roland Dreier References: <20200102001823.21976-1-baolu.lu@linux.intel.com> <20200102001823.21976-23-baolu.lu@linux.intel.com> <567f1506-4a13-535b-ce41-aac079941510@linux.intel.com> From: Lu Baolu Message-ID: <12401c44-7e99-4aff-9014-d8eb8cb29a33@linux.intel.com> Date: Thu, 2 Jan 2020 10:34:02 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Cc: Jim Yan , iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi, On 1/2/20 10:25 AM, Roland Dreier wrote: >> We saw more devices with the same mismatch quirk. So maintaining them in >> a quirk table will make it more readable and maintainable. > > I guess I disagree about the maintainable part, given that this patch > already regresses Broadwell NTB. > > I'm not even sure what the DMAR table says about NTB on my Skylake > systems, exactly because the existing code means I did not have any > problems. But we might need to add device 201Ch too. > > Maybe we don't need the mismatch check at all? Your patch sets the > quirk if any possibly mismatching device is present in the system, so > we'll ignore any scope mismatch on a system with, say, the 8086:2020 > NVMe host in it. So could we just drop the check completely and not > have a quirk to disable the check? Fair enough. Instead of no check, how about putting a pr_info() there and give end user a chance to know this? Best regards, -baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu