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 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 3EC5BC07E9C for ; Thu, 8 Jul 2021 08:09:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26BC861CC4 for ; Thu, 8 Jul 2021 08:09:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231233AbhGHILn (ORCPT ); Thu, 8 Jul 2021 04:11:43 -0400 Received: from 8bytes.org ([81.169.241.247]:33194 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231195AbhGHILm (ORCPT ); Thu, 8 Jul 2021 04:11:42 -0400 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 Cc: Will Deacon , Robin Murphy , Bjorn Andersson , Ulf Hansson , Adrian Hunter , Bjorn Helgaas , John Garry , Rob Clark , quic_c_gdjako@quicinc.com, Saravana Kannan , Rajat Jain , Sai Prakash Ranjan , Veerabhadrarao Badiganti , Linux MMC List , linux-arm-msm , linux-pci@vger.kernel.org, "list@263.net:IOMMU DRIVERS , Joerg Roedel ," , Sonny Rao , Joel Fernandes , Andrew Morton , Jonathan Corbet , Jordan Crouse , Konrad Dybcio , Krishna Reddy , "Maciej W. Rozycki" , Nicolin Chen , "Paul E. McKenney" , Peter Zijlstra , Randy Dunlap , Thierry Reding , Viresh Kumar , Vlastimil Babka , Linux ARM , Linux Doc Mailing List , LKML 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-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org 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 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 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=-4.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 BEC11C07E96 for ; Thu, 8 Jul 2021 08:10:43 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 6AB8961CD5 for ; Thu, 8 Jul 2021 08:10:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6AB8961CD5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=w+yUlDqOTood2ucAPEWif6Se+/Uy4EVwd1QPMJOFjjs=; b=koHCUfqh15YtWJ LrAqrTkXHU9zNPP99JEhtm8fSuSb79mWToTpHdQX0d3KX7eCIJWl+6bHn7dE9pNQ4Guvt5DKhYj5h TUyh81uJ7bGraFrLxIOak22Lce94TKUfEqoKZT5Vk2usk63cHghdbrMmGAhi4lGidQ9BfE0lk67ut jRWK4/Hpqrx9k0mOnJlshdriwkFP6BZucqwd7BnbNOY1tHCcWWeevjoWioEY6US1Elp3a55COPJeH 0C8SN78vj8mpuAAjcjulA8DxJEkOAusb3JtgqTEthTCh0eWvnPGRxv1izD6BPFgqckYkNuS7cmNQf 77rGGVoPeoEGVzBSPr+Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m1P5o-00GGm8-QV; Thu, 08 Jul 2021 08:09:08 +0000 Received: from 8bytes.org ([81.169.241.247] helo=theia.8bytes.org) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1m1P5k-00GGkq-U8 for linux-arm-kernel@lists.infradead.org; Thu, 08 Jul 2021 08:09:06 +0000 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: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210708_010905_181777_38557768 X-CRM114-Status: GOOD ( 14.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ulf Hansson , Linux Doc Mailing List , Peter Zijlstra , linux-pci@vger.kernel.org, Konrad Dybcio , Jordan Crouse , Thierry Reding , Joel Fernandes , Rajat Jain , Will Deacon , Rob Clark , Sai Prakash Ranjan , Saravana Kannan , Jonathan Corbet , quic_c_gdjako@quicinc.com, Linux ARM , Viresh Kumar , Veerabhadrarao Badiganti , "Paul E. McKenney" , linux-arm-msm , John Garry , Nicolin Chen , Bjorn Helgaas , Bjorn Andersson , 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" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel