Re: AMD KVM Pci Passthrough reports device busy

[Andreas Hartmann <andihartmann@01019freenet.de>]

Andreas Hartmann wrote:
[...]
> I tried to run qemu-system-x86_64 but got this error on startup:
> 
> qemu-system-x86_64: -device vfio-pci,host=06:07.0,id=hostdev0,bus=pci.0,addr=0x5: vfio: failed to set iommu for container: Operation not permitted
> 
> qemu-system-x86_64: -device vfio-pci,host=06:07.0,id=hostdev0,bus=pci.0,addr=0x5: vfio: failed to setup container for group 9
> 
> qemu-system-x86_64: -device vfio-pci,host=06:07.0,id=hostdev0,bus=pci.0,addr=0x5: vfio: failed to get group 9
> **
> ERROR:qom/object.c:389:object_delete: assertion failed: (obj->ref == 0)
> 
> 
> I started qemu-system-x86_64 with this option among others 
> 
> -device vfio-pci,host=06:07.0,id=hostdev0,bus=pci.0,addr=0x5
> 
> after all of the devices have been added to pci-stub but 06:07.0, which was added to vfio-pci.
> 
> 
> Could you please tell me, why the operation isn't permitted? I started
> qemu-system-x86_64 as root.

I straced the call with strace and got the following error:

...
8048  open("/usr/local/share/qemu/pxe-virtio.rom", O_RDONLY) = 14
8048  lseek(14, 0, SEEK_END)            = 60416
8048  lseek(14, 0, SEEK_SET)            = 0
8048  read(14, "U\252v\351\217\0z\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\177\0
\0<\0\365\274\266\16"..., 60416) = 60416
8048  close(14)                         = 0
8048  stat("/sys/bus/pci/devices/0000:06:07.0/", {st_mode=S_IFDIR|0755,
st_size=0, ...}) = 0
8048  readlink("/sys/bus/pci/devices/0000:06:07.0/iommu_group",
"../../../../kernel/iommu_groups/9"..., 4096) = 33
8048  open("/dev/vfio/9", O_RDWR)       = 14
8048  ioctl(14, 0x3b67, 0x7fff237d5ac0) = 0
8048  open("/dev/vfio/vfio", O_RDWR)    = 15
8048  ioctl(15, 0x3b64, 0xf)            = 0
8048  ioctl(15, 0x3b65, 0x1)            = 1
8048  ioctl(14, 0x3b68, 0x7fff237d5ad8) = 0
8048  ioctl(15, 0x3b66, 0x1)            = -1 EPERM (Operation not permitted)
...

/dev/vfio # ls -l
total 0
crw-rw-rw- 1 root root 250, 1 Jun  5 17:42 9
crw-rw-rw- 1 root root 250, 0 Jun  5 17:41 vfio



Kind regards,
Andreas