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=-8.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 79986C433E2 for ; Tue, 8 Sep 2020 15:29:18 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 35D8F22450 for ; Tue, 8 Sep 2020 15:29:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="0Dp7mE5z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 35D8F22450 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=cw1BqwdHD3K41X1ZcGX0BaCHZIChFQsh3cOLL9S1ad4=; b=0Dp7mE5z2q3UQuwBQ1piJkcCm FeecBN5wzFGv+USt+lD6nm85lWuVByyWKmI9hKJak6iWxwPCKMDuzAn8JgIrIXpEmQxc/INWOaTKn WWROPBj3t37wGXxhoZ6YOfaPdKEch5Mecmlpx6yKckRe9bFCd+xXFfQWrI9cglTMp79LNiiE6i9l6 1QSJMFl+nK2SaIy/9Fnv0gjLT8qTpPP6uCvjjT5zkBOuxvlQWGB7qB0Jt6AhWgem/Kcj0Y559k5UT XcPaplIYT+3A7exCztAQzLj3sZk01gn1ut8sSiyoz6XxTsvDttCuBofjrkNEDY4dawG2riy0LS/sL a1yE9c8WA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kFfYQ-0004Hf-V9; Tue, 08 Sep 2020 15:29:07 +0000 Received: from mga01.intel.com ([192.55.52.88]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kFfYN-0004GJ-Ln; Tue, 08 Sep 2020 15:29:04 +0000 IronPort-SDR: 1XtrxOZt7aDvIs6B3N/QzJBSO7PRyqkph1LjdR7uxIRK45WEZKDfeH8lmzo4vtAQIkWFRPUFv2 r/eLplXKMBWQ== X-IronPort-AV: E=McAfee;i="6000,8403,9738"; a="176210240" X-IronPort-AV: E=Sophos;i="5.76,406,1592895600"; d="scan'208";a="176210240" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Sep 2020 08:28:50 -0700 IronPort-SDR: OqiPE0Cn/mbaoFglvyhAf2rWnLm6JquwW+AKzi6KXAQYqzMCNSFdbI9D+UGi2vd+sJzRv/8Kvj Oe6qN0U8cxmQ== X-IronPort-AV: E=Sophos;i="5.76,406,1592895600"; d="scan'208";a="480068519" Received: from sderix-mobl1.ger.corp.intel.com (HELO [10.214.213.131]) ([10.214.213.131]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Sep 2020 08:28:38 -0700 Subject: Re: [Intel-gfx] [PATCH 0/8] Convert the intel iommu driver to the dma-iommu api To: Logan Gunthorpe , Tom Murphy References: <20191221150402.13868-1-murphyt7@tcd.ie> <465815ae-9292-f37a-59b9-03949cb68460@deltatee.com> <20200529124523.GA11817@infradead.org> <33137cfb-603c-86e8-1091-f36117ecfaf3@deltatee.com> <766525c3-4da9-6db7-cd90-fb4b82cd8083@deltatee.com> From: Tvrtko Ursulin Organization: Intel Corporation UK Plc Message-ID: <60a82319-cbee-4cd1-0d5e-3c407cc51330@linux.intel.com> Date: Tue, 8 Sep 2020 16:28:35 +0100 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: <766525c3-4da9-6db7-cd90-fb4b82cd8083@deltatee.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200908_112903_839944_49127633 X-CRM114-Status: GOOD ( 30.71 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvm@vger.kernel.org, David Airlie , dri-devel@lists.freedesktop.org, Bjorn Andersson , linux-tegra@vger.kernel.org, Julien Grall , Will Deacon , Marek Szyprowski , Jean-Philippe Brucker , linux-samsung-soc@vger.kernel.org, Marc Zyngier , Krzysztof Kozlowski , Jonathan Hunter , Christoph Hellwig , linux-rockchip@lists.infradead.org, Andy Gross , Gerald Schaefer , linux-s390@vger.kernel.org, linux-arm-msm@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-mediatek@lists.infradead.org, Matthias Brugger , Thomas Gleixner , virtualization@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, Robin Murphy , Cornelia Huck , Linux Kernel Mailing List , iommu@lists.linux-foundation.org, Kukjin Kim , David Woodhouse Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org Hi, On 27/08/2020 22:36, Logan Gunthorpe wrote: > On 2020-08-23 6:04 p.m., Tom Murphy wrote: >> I have added a check for the sg_dma_len == 0 : >> """ >> } __sgt_iter(struct scatterlist *sgl, bool dma) { >> struct sgt_iter s = { .sgp = sgl }; >> >> + if (sgl && sg_dma_len(sgl) == 0) >> + s.sgp = NULL; >> >> if (s.sgp) { >> ..... >> """ >> at location [1]. >> but it doens't fix the problem. > > Based on my read of the code, it looks like we also need to change usage > of sgl->length... Something like the rough patch below, maybe? This thread was brought to my attention and I initially missed this reply. Essentially I came to the same conclusion about the need to use sg_dma_len. One small correction below: > Also, Tom, do you have an updated version of the patchset to convert the > Intel IOMMU to dma-iommu available? The last one I've found doesn't > apply cleanly (I'm assuming parts of it have been merged in slightly > modified forms). > > Thanks, > > Logan > > -- > > diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h > b/drivers/gpu/drm/i915/i915 > index b7b59328cb76..9367ac801f0c 100644 > --- a/drivers/gpu/drm/i915/i915_scatterlist.h > +++ b/drivers/gpu/drm/i915/i915_scatterlist.h > @@ -27,13 +27,19 @@ static __always_inline struct sgt_iter { > } __sgt_iter(struct scatterlist *sgl, bool dma) { > struct sgt_iter s = { .sgp = sgl }; > > + if (sgl && !sg_dma_len(s.sgp)) I'd extend the condition to be, just to be safe: if (dma && sgl && !sg_dma_len(s.sgp)) > + s.sgp = NULL; > + > if (s.sgp) { > s.max = s.curr = s.sgp->offset; > - s.max += s.sgp->length; > - if (dma) > + > + if (dma) { > + s.max += sg_dma_len(s.sgp); > s.dma = sg_dma_address(s.sgp); > - else > + } else { > + s.max += s.sgp->length; > s.pfn = page_to_pfn(sg_page(s.sgp)); > + } Otherwise has this been tested or alternatively how to test it? (How to repro the issue.) Regards, Tvrtko _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek