Hi guys, Im trying to set up vga passthrough. I use the latest mainline kernel (3.12rc5) and patched qemu (1.6.50). When i try to start a VM using this command: qemu-system-x86_64 -enable-kvm -M q35 -m 1024 -cpu qemu64 -bios /usr/share/qemu/bios.bin -vga none -device ioh3420,bus=pcie.0,addr=1c.0,multifunction=on,port=1,chassis=1,id=root.1 -device vfio-pci,host=06:00.0,bus=root.1,multifunction=on,x-vga=on -device vfio-pci,host=06:00.1,bus=root.1 The screen attached to the passthroughed GPU turns on but does not show any output. Also I get some warnings from amd_iommu and my kernel messages are full of AMD-Vi messages: "AMD-Vi: Completion-Wait loop timed out" and "AMD-Vi: Event logged [IOTLB_INV_TIMEOUT device=06:00.0 address=0x0000000438544b90" If i dont stop the qemu process this eventually forces me to reboot since the host gets unusable. I uploaded the whole dmesg output, if its of any help here: http://pastebin.com/ki13dqEd My hardware is an AMD FX-8350 with an Gigabyte 970A-UD3 and a Gigabyte 7870OC. Any help is much appreciated, thanks in advance!
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