Re: [Qemu-discuss] Error starting domain: vfio-pci

[Gabriel Laupre]

> Yes, indeed it is. What distro is this ? Do you have SELinux or any other security feature enabled ? Can you please verify that the file has a appropriate label if SELinux is enabled ? (ls -lZ /dev/vfio/vfio)
My distrib:

address@hidden ~]# cat /proc/version

Linux version 3.10.0-229.1.2.el7.x86_64 (address@hidden) (gcc version 4.8.2 20140120 (Red Hat 4.8.2-16) (GCC) ) #1 SMP Fri Mar 27 03:04:26 UTC 2015

address@hidden ~]# cat /etc/centos-release

CentOS Linux release 7.1.1503 (Core)

address@hidden ~]# ls -lZ /dev/vfio/vfio

crw-rw-rw- root root ?                                /dev/vfio/vfio

SELinux is disabled:

address@hidden ~]# getenforce

Disabled

I guess no other security feature is enabled that I am aware of. I once had a message saying that it can be one of the following issues (listing the 5). So I guess it can be any combination of those issues, even something completely different.

libvirtError: internal error: process exited while connecting to monitor: 2015-05-19T21:46:21.935043Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: vfio: failed to open /dev/vfio/vfio: Operation not permitted
2015-05-19T21:46:21.935091Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: vfio: failed to setup container for group 24
2015-05-19T21:46:21.935107Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: vfio: failed to get group 24
2015-05-19T21:46:21.935135Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: Device initialization failed.
2015-05-19T21:46:21.935157Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: Device 'vfio-pci' could not be initialized

2015-05-19 21:17 GMT-08:00 Bandan Das <address@hidden>:

> On May 20, 2015, at 12:29 AM, Gabriel Laupre <address@hidden> wrote:
>
> Thank Bandan,
>
>
> > Assuming you are on an intel box, have you booted your kernel with intel_iommu=on ?
> Yes, I have booted my kernel with the intel_iommu=on. (I don't remember how to check that now though ^^)
>
> > Please paste the output of dmesg | grep -e DMAR -e IOMMU ?
> address@hidden ~]# dmesg | grep -e DMAR -e IOMMU
> [    0.000000] ACPI: DMAR 00000000bf79e0c0 00118 (v01    AMI  OEMDMAR 00000001 MSFT 00000097)
> [    0.000000] Intel-IOMMU: enabled
> [    0.039149] dmar: IOMMU 0: reg_base_addr fbffe000 ver 1:0 cap c90780106f0462 ecap f020f6
> [    0.550126] IOMMU 0 0xfbffe000: using Queued invalidation
> [    0.550131] IOMMU: Setting RMRR:
> [    0.550149] IOMMU: Setting identity map for device 0000:00:1a.0 [0xbf7ec000 - 0xbf7fffff]
> [    0.550184] IOMMU: Setting identity map for device 0000:00:1a.1 [0xbf7ec000 - 0xbf7fffff]
> [    0.550211] IOMMU: Setting identity map for device 0000:00:1a.2 [0xbf7ec000 - 0xbf7fffff]
> [    0.550241] IOMMU: Setting identity map for device 0000:00:1a.7 [0xbf7ec000 - 0xbf7fffff]
> [    0.550272] IOMMU: Setting identity map for device 0000:00:1d.0 [0xbf7ec000 - 0xbf7fffff]
> [    0.550302] IOMMU: Setting identity map for device 0000:00:1d.1 [0xbf7ec000 - 0xbf7fffff]
> [    0.550329] IOMMU: Setting identity map for device 0000:00:1d.2 [0xbf7ec000 - 0xbf7fffff]
> [    0.550358] IOMMU: Setting identity map for device 0000:00:1d.7 [0xbf7ec000 - 0xbf7fffff]
> [    0.550375] IOMMU: Setting identity map for device 0000:00:1a.0 [0xec000 - 0xeffff]
> [    0.550387] IOMMU: Setting identity map for device 0000:00:1a.1 [0xec000 - 0xeffff]
> [    0.550399] IOMMU: Setting identity map for device 0000:00:1a.2 [0xec000 - 0xeffff]
> [    0.550410] IOMMU: Setting identity map for device 0000:00:1a.7 [0xec000 - 0xeffff]
> [    0.550421] IOMMU: Setting identity map for device 0000:00:1d.0 [0xec000 - 0xeffff]
> [    0.550433] IOMMU: Setting identity map for device 0000:00:1d.1 [0xec000 - 0xeffff]
> [    0.550444] IOMMU: Setting identity map for device 0000:00:1d.2 [0xec000 - 0xeffff]
> [    0.550458] IOMMU: Setting identity map for device 0000:00:1d.7 [0xec000 - 0xeffff]
> [    0.550471] IOMMU: Prepare 0-16MiB unity mapping for LPC
> [    0.550483] IOMMU: Setting identity map for device 0000:00:1f.0 [0x0 - 0xffffff]
>

Yeah, this looks ok. Actually, taking a second look, I can’t think of anyway how this could be related to file permissions on /dev/vfio/vfio.

> > Why does opening /dev/vfio/vfio fail ? Can you please confirm that you have read/write permissions as the user you are trying to run ?
> address@hidden ~]# cd /dev/vfio/
> address@hidden vfio]# ls -la | grep vfio
> crw-rw-rw-  1 root root 10, 196 May 18 11:54 vfio
> The right should be okay I guess.
>
Yes, indeed it is. What distro is this ? Do you have SELinux or any other security feature enabled ? Can you please verify that the file has a appropriate label if SELinux is enabled ? (ls -lZ /dev/vfio/vfio)

Bandan

>
>
>
> 2015-05-19 18:54 GMT-08:00 Bandan Das <address@hidden>:
>
> Hello Gabriel,
>
> > On May 19, 2015, at 8:03 PM, Gabriel Laupre <address@hidden> wrote:
> >
> > Hello everyone,
> >
> > I am using a Centos 7.1 machine with the kernel 3.10.229. I want to use my host with SR-IOV to use a virtual function on my NIC as the vNIC in my new VM.
> >
> > I have an instance started with a old NIC using macvtap that I want to change. I am using the
> > virsh edit instance-00000034
> > command to edit the XML configuration to add the new device I want to attach.
> …
> Assuming you are on an intel box, have you booted your kernel with intel_iommu=on ?
> Please paste the output of dmesg | grep -e DMAR -e IOMMU ?
>
> > When I try to reboot the VM I get this error:
> > Error starting domain: internal error: process exited while connecting to monitor: 2015-05-19T21:46:21.935043Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: vfio: failed to open /dev/vfio/vfio: Operation not permitted
> Why does opening /dev/vfio/vfio fail ? Can you please confirm that you have read/write permissions as the user you are trying to run ?
>
> > 2015-05-19T21:46:21.935091Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: vfio: failed to setup container for group 24
> > 2015-05-19T21:46:21.935107Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: vfio: failed to get group 24
> > 2015-05-19T21:46:21.935135Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: Device initialization failed.
> > 2015-05-19T21:46:21.935157Z qemu-kvm: -device vfio-pci,host=04:10.4,id=hostdev0,bus=pci.0,addr=0x3: Device 'vfio-pci' could not be initialized
> >
> > total Trace here: http://sprunge.us/XZFB
> >
> > Any idea how to fix that?
> >
> > Thank you very much :)
> >
> > Gabriel
> >
>
>