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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 C395EC10DAA for ; Sat, 12 Sep 2020 03:28:19 +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 59451221E7 for ; Sat, 12 Sep 2020 03:28:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 59451221E7 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 E60F42034B; Sat, 12 Sep 2020 03:28:18 +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 tfJkrn2lr35j; Sat, 12 Sep 2020 03:28:16 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id B1CAB20468; Sat, 12 Sep 2020 03:28:16 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 9E975C0859; Sat, 12 Sep 2020 03:28:16 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id E4362C0051 for ; Sat, 12 Sep 2020 03:28:15 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id CCFCE20468 for ; Sat, 12 Sep 2020 03:28:15 +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 e+m+P+6AMxNH for ; Sat, 12 Sep 2020 03:28:13 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by silver.osuosl.org (Postfix) with ESMTPS id 6179720464 for ; Sat, 12 Sep 2020 03:28:13 +0000 (UTC) IronPort-SDR: h+o3O6cRXh8QWA4A2aaJUQ+bpuBqsNs46xFVtDsAC6eBT/cQGmSFuM6LAIdiI7m8C4+2rO1kLx iJL/TxvNiX1w== X-IronPort-AV: E=McAfee;i="6000,8403,9741"; a="159826807" X-IronPort-AV: E=Sophos;i="5.76,418,1592895600"; d="scan'208";a="159826807" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Sep 2020 20:28:13 -0700 IronPort-SDR: lef0v+QCekDhqfdMiRck6tJidoLuDv+5TRh/0TSl6O5c3kHYFVjclcSqorlys+Cb/AcY2EI3sQ t4ULR7HabTfQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,418,1592895600"; d="scan'208";a="408321414" Received: from allen-box.sh.intel.com ([10.239.159.139]) by fmsmga001.fm.intel.com with ESMTP; 11 Sep 2020 20:28:10 -0700 From: Lu Baolu To: Joerg Roedel , Tom Murphy , David Woodhouse , Christoph Hellwig Subject: [PATCH v3 4/6] iommu: Add quirk for Intel graphic devices in map_sg Date: Sat, 12 Sep 2020 11:21:58 +0800 Message-Id: <20200912032200.11489-5-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200912032200.11489-1-baolu.lu@linux.intel.com> References: <20200912032200.11489-1-baolu.lu@linux.intel.com> Cc: Tvrtko Ursulin , Ashok Raj , Intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, 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: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Combining the sg segments exposes a bug in the Intel i915 driver which causes visual artifacts and the screen to freeze. This is most likely because of how the i915 handles the returned list. It probably doesn't respect the returned value specifying the number of elements in the list and instead depends on the previous behaviour of the Intel iommu driver which would return the same number of elements in the output list as in the input list. Signed-off-by: Tom Murphy Signed-off-by: Lu Baolu --- drivers/iommu/dma-iommu.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 1a1da22e5a5e..fc19f1fb9413 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -880,6 +880,33 @@ static int __finalise_sg(struct device *dev, struct scatterlist *sg, int nents, unsigned int cur_len = 0, max_len = dma_get_max_seg_size(dev); int i, count = 0; + /* + * The Intel graphic driver is used to assume that the returned + * sg list is not combound. This blocks the efforts of converting + * Intel IOMMU driver to dma-iommu api's. Add this quirk to make the + * device driver work and should be removed once it's fixed in i915 + * driver. + */ + if (IS_ENABLED(CONFIG_DRM_I915) && dev_is_pci(dev) && + to_pci_dev(dev)->vendor == PCI_VENDOR_ID_INTEL && + (to_pci_dev(dev)->class >> 16) == PCI_BASE_CLASS_DISPLAY) { + for_each_sg(sg, s, nents, i) { + unsigned int s_iova_off = sg_dma_address(s); + unsigned int s_length = sg_dma_len(s); + unsigned int s_iova_len = s->length; + + s->offset += s_iova_off; + s->length = s_length; + sg_dma_address(s) = dma_addr + s_iova_off; + sg_dma_len(s) = s_length; + dma_addr += s_iova_len; + + pr_info_once("sg combining disabled due to i915 driver\n"); + } + + return nents; + } + for_each_sg(sg, s, nents, i) { /* Restore this segment's original unaligned fields first */ unsigned int s_iova_off = sg_dma_address(s); -- 2.17.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu