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=-4.0 required=3.0 tests=BAYES_00, 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 41B28C07E96 for ; Thu, 8 Jul 2021 08:09:07 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 DDA7261CE9 for ; Thu, 8 Jul 2021 08:09:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DDA7261CE9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id A4F93400EF; Thu, 8 Jul 2021 08:09:06 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tDZRtxMWVZec; Thu, 8 Jul 2021 08:09:05 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp2.osuosl.org (Postfix) with ESMTPS id 9D5574019B; Thu, 8 Jul 2021 08:09:05 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7D683C001A; Thu, 8 Jul 2021 08:09:05 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [IPv6:2605:bc80:3010::136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 00891C000E for ; Thu, 8 Jul 2021 08:09:04 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id D46CC606B8 for ; Thu, 8 Jul 2021 08:09:03 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Xf7ve_nW5VYJ for ; Thu, 8 Jul 2021 08:09:03 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp3.osuosl.org (Postfix) with ESMTPS id 1CF6E605AE for ; Thu, 8 Jul 2021 08:09:02 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id B94FA312; Thu, 8 Jul 2021 10:08:58 +0200 (CEST) Date: Thu, 8 Jul 2021 10:08:56 +0200 From: Joerg Roedel To: Doug Anderson Subject: Re: [PATCH v2 0/3] iommu: Enable non-strict DMA on QCom SD/MMC Message-ID: References: <20210624171759.4125094-1-dianders@chromium.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Cc: Ulf Hansson , Linux Doc Mailing List , Peter Zijlstra , linux-pci@vger.kernel.org, Konrad Dybcio , Thierry Reding , Joel Fernandes , Rajat Jain , Will Deacon , Rob Clark , Saravana Kannan , Jonathan Corbet , quic_c_gdjako@quicinc.com, Linux ARM , Viresh Kumar , Veerabhadrarao Badiganti , "Paul E. McKenney" , linux-arm-msm , Bjorn Helgaas , Sonny Rao , Vlastimil Babka , Randy Dunlap , Linux MMC List , Adrian Hunter , LKML , "list@263.net:IOMMU DRIVERS , Joerg Roedel , " , Andrew Morton , Robin Murphy , "Maciej W. Rozycki" 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Wed, Jul 07, 2021 at 01:00:13PM -0700, Doug Anderson wrote: > a) Nothing is inherently broken with my current approach. > > b) My current approach doesn't make anybody terribly upset even if > nobody is totally in love with it. Well, no, sorry :) I don't think it is a good idea to allow drivers to opt-out of the strict-setting. This is a platform or user decision, and the driver should accept whatever it gets. So the real question is still why strict is the default setting and how to change that. Or document for the users that want performance how to change the setting, so that they can decide. Regards, Joerg _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu