
Hi folks, Has anyone encountered the following PCI passthrough error? error: internal error Process exited while reading console \ log output: char device redirected to /dev/pts/1 assigned_dev_pci_read: pread failed, ret = 0 errno = 2 It's produced after I've detached the PCI device from the base OS and have tried to start up the guest domain. To get to this point, I mostly followed these instructions: http://docs.fedoraproject.org/en-US/Fedora/13/html/Virtualization_Guide/chap... The distro I'm using is Debian squeeze, which by default comes with libvirt 0.8.3 and qemu-kvm 0.12.5, although to avoid a different PCI passthrough error, I used Debian backports for squeeze to upgrade them to libvirt 0.9.8 and qemu-kvm 1.0. The motherboard involved has VT-d support, which I've enabled with the "intel_iommu=on" kernel option (dmesg shows "Intel-IOMMU: enabled"). I did not bother with setsebool because SELinux is disabled. According to lspci, the device I want to pass through to the guest domain, a USB controller, has bus/slot/function 00:1a.0, so I added the following stanza to the <devices> section of my guest domain: <hostdev mode='subsystem' type='pci' managed='yes'> <source> <address domain='0x0000' bus='0x00' slot='0x1a' function='0x0'/> </source> </hostdev> Actually, every time I save this configuration, libvirt changes it to: <hostdev mode='subsystem' type='pci' managed='yes'> <source> <address domain='0x0000' bus='0x00' slot='0x1a' function='0x0'/> </source> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> </hostdev> Huh, slot 5? I don't have any PCI devices that use slot 5. Well, at least the system doesn't complain, but I worry that this might be a symptom of something more serious. Anyway, I'd be very grateful if anyone has any tips on how I might avoid the aforementioned error and get PCI passthrough to to work. Thanks, Jaap