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

[Bandan Das]

> 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
> >
> 
>