Quoting Jaap Winius <jwinius@umrk.nl>:
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 turns out this is a KVM bug related to the Linux 2.6.32-5-amd64 kernel I was using with Debian squeeze. I fixed this by using Debian backports again to upgrade to the 3.2.0-0.bpo.2-amd64 kernel. Unfortunately, now when I try to get PCI passthrough to work I get this: error: Unable to read from monitor: Connection reset by peer Actually, when I checked to see if it would still work without the PCI passthrough stuff I seemed to get no errors, but it wouldn't start either. Then I found this kvm error in the guest's log: memory_region_add_subregion_common: Assertion `!subregion->parent' failed. Luckily, I found I could fix this by changing the machine type from pc-0.12 to pc-1.0 (I changed that with "virsh edit ..."). However, I still get the "Unable to read from monitor" error if I activate PCI passthrough, and I found some more in the guest's log too: char device redirected to /dev/pts/1 PCI region 0 at address 0xfb207000 has size 0x400, which is not a multiple of 4K. You might experience some performance hit due to that. No IOMMU found. Unable to assign device "hostdev0" kvm: -device pci-assign,host=00:1a.0,id=hostdev0,configfd=20,bus=pci.0,addr=0x5: Device 'pci-assign' could not be initialized 2012-03-30 00:49:58.209+0000: shutting down No IOMMU?? But, this new 3.2.0-0.bpo.2-amd64 kernel says "Intel-IOMMU: enabled" (that's from dmesg) when the system boots up, so what am I missing here? Well, whaddaya know. I did some more research on the chipset and found it to be an Intel BD82H61 PCH... http://ark.intel.com/products/52806/Intel-BD82H61-PCH ... which apparently does not support VT-d (have an IOMMU) after all. Doh! The BIOS does include a virtualization option, but I guess it's not about VT-d. I think what would have saved me a lot of time here (besides a better brain) is a simple way to test for the presence of an IOMMU, but I don't know of one. Anyway I guess now it's USB passthrough or bust. Or get a board with an IOMMU. Cheers, Jaap