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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B2A8AC433DF for ; Wed, 8 Jul 2020 02:17:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9320420708 for ; Wed, 8 Jul 2020 02:17:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729255AbgGHCRf (ORCPT ); Tue, 7 Jul 2020 22:17:35 -0400 Received: from mga05.intel.com ([192.55.52.43]:63062 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728479AbgGHCRe (ORCPT ); Tue, 7 Jul 2020 22:17:34 -0400 IronPort-SDR: 2u3KdpWlYtGwmeq5e9lODcvZ8rIikqBqXogmhUMSefsXOldRLFgXhnmVmvAkCzv+ngmmAOG1oJ nUpn6ali0mWA== X-IronPort-AV: E=McAfee;i="6000,8403,9675"; a="232587574" X-IronPort-AV: E=Sophos;i="5.75,326,1589266800"; d="scan'208";a="232587574" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jul 2020 19:17:34 -0700 IronPort-SDR: TUGrLOQs9vhlflb9p3/9zdjZy2bptRKESKoPv85baFE2PqNBXRXxQxjxVVzJzlHDoBYkF6Le4k hGFimBrBbZ5g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,326,1589266800"; d="scan'208";a="457323827" Received: from allen-box.sh.intel.com (HELO [10.239.159.139]) ([10.239.159.139]) by orsmga005.jf.intel.com with ESMTP; 07 Jul 2020 19:17:32 -0700 Cc: baolu.lu@linux.intel.com, iommu@lists.linux-foundation.org, Kevin Tian , Ashok Raj , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/4] iommu/vt-d: Report page request faults for guest SVA To: Jean-Philippe Brucker References: <20200706002535.9381-1-baolu.lu@linux.intel.com> <20200706002535.9381-4-baolu.lu@linux.intel.com> <20200707112344.GB159413@myrica> From: Lu Baolu Message-ID: <3d0680fc-afba-e642-f88f-aac4e276c5a5@linux.intel.com> Date: Wed, 8 Jul 2020 10:13:02 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200707112344.GB159413@myrica> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jean, On 7/7/20 7:23 PM, Jean-Philippe Brucker wrote: > On Mon, Jul 06, 2020 at 08:25:34AM +0800, Lu Baolu wrote: >> A pasid might be bound to a page table from a VM guest via the iommu >> ops.sva_bind_gpasid. In this case, when a DMA page fault is detected >> on the physical IOMMU, we need to inject the page fault request into >> the guest. After the guest completes handling the page fault, a page >> response need to be sent back via the iommu ops.page_response(). >> >> This adds support to report a page request fault. Any external module >> which is interested in handling this fault should regiester a notifier >> callback. >> >> Co-developed-by: Jacob Pan >> Signed-off-by: Jacob Pan >> Co-developed-by: Liu Yi L >> Signed-off-by: Liu Yi L >> Signed-off-by: Lu Baolu >> --- > [...] >> +static int >> +intel_svm_prq_report(struct device *dev, struct page_req_dsc *desc) >> +{ >> + struct iommu_fault_event event; >> + u8 bus, devfn; >> + >> + memset(&event, 0, sizeof(struct iommu_fault_event)); >> + bus = PCI_BUS_NUM(desc->rid); >> + devfn = desc->rid & 0xff; >> + >> + /* Fill in event data for device specific processing */ >> + event.fault.type = IOMMU_FAULT_PAGE_REQ; >> + event.fault.prm.addr = desc->addr; >> + event.fault.prm.pasid = desc->pasid; >> + event.fault.prm.grpid = desc->prg_index; >> + event.fault.prm.perm = prq_to_iommu_prot(desc); >> + >> + /* >> + * Set last page in group bit if private data is present, >> + * page response is required as it does for LPIG. >> + */ >> + if (desc->lpig) >> + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE; >> + if (desc->pasid_present) >> + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID; > > Do you also need to set IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID? I added > the flag to deal with devices that do not want a PASID value in their PRI > response (bit 15 in the PCIe Page Request Status Register): > https://lore.kernel.org/linux-iommu/20200616144712.748818-1-jean-philippe@linaro.org/ > (applied by Joerg for v5.9) > > Grepping for pci_prg_resp_pasid_required() in intel/iommu.c it seems to > currently reject devices that do not want a PASID in a PRI response, so I > think you can set this flag unconditionally for now. Yes. You are right. I will set this flag in the next version. Best regards, baolu > > Thanks, > Jean > >> + if (desc->priv_data_present) { >> + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE; >> + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PRIV_DATA; >> + memcpy(event.fault.prm.private_data, desc->priv_data, >> + sizeof(desc->priv_data)); >> + } >> + >> + return iommu_report_device_fault(dev, &event); >> +}