From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: [Qemu-devel] VFIO VGA test branches Date: Tue, 28 May 2013 07:53:45 -0600 Message-ID: <1369749225.2646.227.camel@ul30vt.home> References: <1367621792.22436.49.camel@ul30vt.home> <1368478534.14279.201.camel@ori.omang.mine.nu> <1368483819.5520.101.camel@ul30vt.home> <1368977758.14279.329.camel@ori.omang.mine.nu> <1369023350.5520.301.camel@ul30vt.home> <1369084319.14279.373.camel@ori.omang.mine.nu> <1369719202.4027.118.camel@ori.omang.mine.nu> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: qemu-devel , kvm To: Knut Omang Return-path: Received: from mx1.redhat.com ([209.132.183.28]:22534 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752235Ab3E1Nxw (ORCPT ); Tue, 28 May 2013 09:53:52 -0400 In-Reply-To: <1369719202.4027.118.camel@ori.omang.mine.nu> Sender: kvm-owner@vger.kernel.org List-ID: On Tue, 2013-05-28 at 07:33 +0200, Knut Omang wrote: > > I noticed this warning in the host log - I suppose it is unrelated but > thought I'd mention it just in case there is some side effect I do not > understand here: > > [ 0.538124] IOMMU: Setting identity map for device 0000:00:1f.0 [0x0 - 0xffffff] > [ 0.538619] PCI-DMA: Intel(R) Virtualization Technology for Directed I/O > [ 0.538676] ------------[ cut here ]------------ > [ 0.538681] WARNING: at drivers/pci/search.c:46 pci_find_upstream_pcie_bridge+0x58/0x80() > [ 0.538683] Hardware name: To be filled by O.E.M. > [ 0.538685] Modules linked in: > [ 0.538687] Pid: 1, comm: swapper/0 Not tainted 3.9.0+ #1 > [ 0.538689] Call Trace: > [ 0.538694] [] warn_slowpath_common+0x7f/0xc0 > [ 0.538697] [] warn_slowpath_null+0x1a/0x20 > [ 0.538699] [] pci_find_upstream_pcie_bridge+0x58/0x80 > [ 0.538703] [] intel_iommu_add_device+0x4b/0x1f0 > [ 0.538706] [] ? bus_set_iommu+0x60/0x60 > [ 0.538708] [] add_iommu_group+0x33/0x60 > [ 0.538712] [] bus_for_each_dev+0x5d/0xa0 > [ 0.538714] [] bus_set_iommu+0x4b/0x60 > [ 0.538718] [] intel_iommu_init+0xa72/0xb9a > [ 0.538722] [] ? memblock_find_dma_reserve+0x13d/0x13d > [ 0.538724] [] pci_iommu_init+0x13/0x3e > [ 0.538727] [] do_one_initcall+0x12a/0x180 > [ 0.538730] [] kernel_init_freeable+0x150/0x1df > [ 0.538732] [] ? do_early_param+0x8c/0x8c > [ 0.538736] [] ? rest_init+0x80/0x80 > [ 0.538738] [] kernel_init+0xe/0xf0 > [ 0.538742] [] ret_from_fork+0x7c/0xb0 > [ 0.538744] [] ? rest_init+0x80/0x80 > [ 0.538749] ---[ end trace f4e8b5168095f9c1 ]--- There's a bug for this: https://bugzilla.kernel.org/show_bug.cgi?id=44881 Chances are your system includes one of the non-compliant PCIe-to-PCI bridges that doesn't include a PCIe capability. So long as you're not assigning anything behind that bridge, it shouldn't matter, but I think we'll setup the wrong grouping and use the wrong source ID for devices behind it. Thanks, Alex