From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ia0-f174.google.com ([209.85.210.174]:45984 "EHLO mail-ia0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752066Ab2LOWRC (ORCPT ); Sat, 15 Dec 2012 17:17:02 -0500 Message-ID: <50CCF6DB.7080204@gmail.com> Date: Sat, 15 Dec 2012 16:16:59 -0600 From: Robert Hancock MIME-Version: 1.0 To: Don Dutile CC: Jason Gao , linux-kernel , linux-pci@vger.kernel.org, kvm Subject: Re: DMAR and DRHD errors[DMAR:[fault reason 06] PTE Read access is not set] Vt-d & intel_iommu References: <50CB9ADC.2020103@redhat.com> In-Reply-To: <50CB9ADC.2020103@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 12/14/2012 03:32 PM, Don Dutile wrote: > On 12/13/2012 04:50 AM, Jason Gao wrote: >> Dear List: >> >> Description of problem: >> After installed Centos 6.3(RHEL6.3) on my Dell R710(lastest >> bios:Version: 6.3.0,Release Date: 07/24/2012) server,and updated >> lastest kernel "2.6.32-279.14.1.el6.x86_64",I want to use the Intel >> 82576 ET Dual Port nic's SR-IOV feature,assigning VFs to kvm guest >> >> appended kernel boot parameter: intel_iommu=on,after boot with the >> following messages: >> >> Dec 13 16:58:15 2 kernel: DRHD: handling fault status reg 2 >> Dec 13 16:58:15 2 kernel: DMAR:[DMA Read] Request device [03:00.0] >> fault addr ffe65000 >> Dec 13 16:58:15 2 kernel: DMAR:[fault reason 06] PTE Read access is >> not set >> Dec 13 16:58:15 2 kernel: DRHD: handling fault status reg 102 >> Dec 13 16:58:15 2 kernel: DMAR:[DMA Read] Request device [03:00.0] >> fault addr ffe8a000 >> Dec 13 16:58:15 2 kernel: DMAR:[fault reason 06] PTE Read access is >> not set >> Dec 13 16:58:15 2 kernel: scsi 0:0:32:0: Enclosure DP >> BACKPLANE 1.07 PQ: 0 ANSI: 5 >> Dec 13 16:58:15 2 kernel: DRHD: handling fault status reg 202 >> Dec 13 16:58:15 2 kernel: DMAR:[DMA Read] Request device [03:00.0] >> fault addr ffe89000 >> Dec 13 16:58:15 2 kernel: DMAR:[fault reason 06] PTE Read access is >> not set >> >> full dmesg detail: >> http://pastebin.com/BzFQV0jU >> lspci -vvv full detail: >> http://pastebin.com/9rP2d1br >> >> >> it's a production server,and I'm not sure if this is a critical >> problem,how to fix it,any help would be greatly appreciated. > > DMAR table does not have an entry for this device to this region. > Once the driver reconfigs/resets the device to stop polling bios-boot > cmd rings and use (new) OS (dma-mapped) rings, there's a period of time > during this transition that the hw is babbling away to an area that is no > longer mapped. Maybe some kind of boot PCI quirk is needed to stop the device DMA activity before enabling the IOMMU?