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=-6.9 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 1BB0EC2BBD0 for ; Tue, 8 Sep 2020 06:10:46 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 B383D206B8 for ; Tue, 8 Sep 2020 06:10:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B383D206B8 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 silver.osuosl.org (Postfix) with ESMTP id 432782291C; Tue, 8 Sep 2020 06:10:45 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id XJzw14vaWHwO; Tue, 8 Sep 2020 06:10:44 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 22722228E2; Tue, 8 Sep 2020 06:10:44 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 0148DC0052; Tue, 8 Sep 2020 06:10:44 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id A3743C0051 for ; Tue, 8 Sep 2020 06:10:42 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 7E3752291C for ; Tue, 8 Sep 2020 06:10:42 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id rJChBOsFF3vg for ; Tue, 8 Sep 2020 06:10:41 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by silver.osuosl.org (Postfix) with ESMTPS id A73E2228E2 for ; Tue, 8 Sep 2020 06:10:41 +0000 (UTC) IronPort-SDR: nD/reGhEOJC0rywvyhGNTnk47h6OyIQy9X0HMzr5bVTsdvoGDhuo2o1SJ99vthWcnvpu5Lr7EA NC2uN1HdxytA== X-IronPort-AV: E=McAfee;i="6000,8403,9737"; a="145801284" X-IronPort-AV: E=Sophos;i="5.76,404,1592895600"; d="scan'208";a="145801284" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Sep 2020 23:10:40 -0700 IronPort-SDR: WV1iGX4PezN4uM+SBYmsobq8wQfeNgX5mSccINOILxX+uqqhJ1fSilEU4XPtxc6P1gSWzvsQfz ZmYSq5PMiL1g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,404,1592895600"; d="scan'208";a="407028868" Received: from allen-box.sh.intel.com (HELO [10.239.159.139]) ([10.239.159.139]) by fmsmga001.fm.intel.com with ESMTP; 07 Sep 2020 23:10:38 -0700 Subject: Re: [PATCH V2 5/5] DO NOT MERGE: iommu: disable list appending in dma-iommu To: Christoph Hellwig , Tom Murphy References: <20200903201839.7327-1-murphyt7@tcd.ie> <20200903201839.7327-6-murphyt7@tcd.ie> <20200907070035.GA25114@infradead.org> <20200908053619.GA15418@infradead.org> <20200908055510.GA19078@infradead.org> From: Lu Baolu Message-ID: <9655fdc9-6ea0-e4c1-e104-a9a8981ecb1e@linux.intel.com> Date: Tue, 8 Sep 2020 14:04:53 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200908055510.GA19078@infradead.org> Content-Language: en-US Cc: intel-gfx@lists.freedesktop.org, Joonas Lahtinen , Linux Kernel Mailing List , Jani Nikula , iommu@lists.linux-foundation.org, Rodrigo Vivi , David Woodhouse 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 Christoph, On 9/8/20 1:55 PM, Christoph Hellwig wrote: > On Tue, Sep 08, 2020 at 06:36:19AM +0100, Christoph Hellwig wrote: >> On Mon, Sep 07, 2020 at 09:18:50PM +0100, Tom Murphy wrote: >>> Yeah we talked about passing an attr to map_sg to disable merging at >>> the following microconfernce: >>> https://linuxplumbersconf.org/event/7/contributions/846/ >>> As far as I can remember everyone seemed happy with that solution. I >>> won't be working on this though as I don't have any more time to >>> dedicate to this. It seems Lu Baolu will take over this. >> >> I'm absolutely again passing a flag. Tha just invites further >> abuse. We need a PCI ID based quirk or something else that can't >> be as easily abused. > > Also, I looked at i915 and there are just three dma_map_sg callers. > The two dmabuf related ones are fixed by Marek in his series, leaving Do you mind telling where can I find Marek's series? Best regards, baolu > just the one in i915_gem_gtt_prepare_pages, which does indeed look > very fishy. But if that one is so hard to fix it can just be replaced > by an open coded for_each_sg loop that contains manual dma_map_page > calls. > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu