From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishank Trivedi Subject: pci passthrough error about insufficient iommu width Date: Wed, 6 Aug 2014 14:22:48 -0700 Message-ID: <53E29CA8.6070806@netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit To: Return-path: Received: from mx12.netapp.com ([216.240.18.77]:36318 "EHLO mx12.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753561AbaHFVWu (ORCPT ); Wed, 6 Aug 2014 17:22:50 -0400 Received: from [10.55.14.11] (nishanks-mbp.wlan.netapp.com [10.55.14.11]) by smtp1.corp.netapp.com (8.13.1/8.13.1/NTAP-1.6) with ESMTP id s76LMnDo028961 for ; Wed, 6 Aug 2014 14:22:49 -0700 (PDT) Sender: kvm-owner@vger.kernel.org List-ID: Hi I'm trying to do a pci-passthrough of Intel 82599 10GbE card, with guest having 8G of memory. I see following error - intel_iommu_map: iommu width (48) is not sufficient for the mapped address (fffffffffe001000) kvm_iommu_map_address:iommu failed to map pfn=45800 I checked IOMMU capability register and SAGAW as well as MGAW are 48bits for both IOMMU. # dmesg | grep ecap dmar: IOMMU 0: reg_base_addr dfff0000 ver 1:0 cap d2078c106f0462 ecap f020fe dmar: IOMMU 1: reg_base_addr bfff0000 ver 1:0 cap d2078c106f0462 ecap f020fe # cat /proc/cpuinfo | grep "address sizes" address sizes : 46 bits physical, 48 bits virtual In DMAR table, I see host address width set to "2D", i.e. 46bit, which is ok as it is same as physical address size. Any suggestions on what might be going wrong here? Thanks, nt