Re: PCI Passthrough, error: The driver 'pci-stub' is occupying your device 0000:08:06.2

James Neave
2011-02-21T22:49:30Z

On Mon, Feb 21, 2011 at 10:25 PM, James Neave <roboj1m@gmail.com> wrote:
> On Mon, Feb 21, 2011 at 9:01 PM, Alex Williamson
> <alex.williamson@redhat.com> wrote:
>> On Mon, 2011-02-21 at 20:31 +0000, James Neave wrote:
>>> On Mon, Feb 14, 2011 at 5:48 PM, Alex Williamson
>>> <alex.williamson@redhat.com> wrote:
>>> > On Sat, 2011-02-12 at 16:04 +0000, James Neave wrote:
>>> >> On Tue, Feb 8, 2011 at 10:17 AM, James Neave <roboj1m@gmail.com> wrote:
>>> >> > On Tue, Feb 8, 2011 at 9:59 AM, Kenni Lund <kenni@kelu.dk> wrote:
>>> >> >> 2011/2/7 Daniel P. Berrange <berrange@redhat.com>:
>>> >> >>> On Sat, Feb 05, 2011 at 04:34:01PM +0000, James Neave wrote:
>>> >> >>>> Hi,
>>> >> >>>>
>>> >> >>>> I'm trying to pass a NOVA-T-500 TV Tuner card through to a gust VM.
>>> >> >>>> I'm getting the error "The driver 'pci-stub' is occupying your device
>>> >> >>>> 0000:08:06.2"
>>> >> >>>
>>> >> >>> This is a rather misleading error message. It is *expected* that
>>> >> >>> pci-stub will occupy the device. Unfortunately the rest of the
>>> >> >>> error messages QEMU is printing aren't much help either, but
>>> >> >>> ultimately something is returning -EBUSY in the PCI device assign
>>> >> >>> step
>>> >> >>
>>> >> >> James, as far as I remember, I had the same issue when I set up my
>>> >> >> system. Looking at my current (working) boot-script, apparently I've
>>> >> >> added a 4th line which removes the pci-stub again as a
>>> >> >> workaround....and it works:
>>> >> >>
>>> >> >> echo "4444 0016" > /sys/bus/pci/drivers/pci-stub/new_id
>>> >> >> echo "0000:04:08.0" > /sys/bus/pci/drivers/ivtv/unbind
>>> >> >> echo "0000:04:08.0" > /sys/bus/pci/drivers/pci-stub/bind
>>> >> >> echo "4444 0016" > /sys/bus/pci/drivers/pci-stub/remove_id
>>> >> >>
>>> >> >> Best regards
>>> >> >> Kenni
>>> >> >>
>>> >> >
>>> >> > Hi Kenni,
>>> >> >
>>> >> > Can I get a bit more information on "boot-script" please? Which file
>>> >> > exaclty have you put this in? Did you write your own service script
>>> >> > and put it in init.d?
>>> >> >
>>> >> > I've tried this:
>>> >> >
>>> >> > echo "8086 10b9" > /sys/bus/pci/drivers/pci-stub/new_id
>>> >> > echo 0000:01:00.0 > /sys/bus/pci/devices/0000:01:00.0/driver/unbind
>>> >> > echo 0000:01:00.0 > /sys/bus/pci/drivers/pci-stub/bind
>>> >> >
>>> >> > I'll try it again with the fourth line added, manually before I start the VM.
>>> >> >
>>> >> > How come yours is 'echo "PCI" > /sys/bus/drivers/DRIVERNAME/unbind'
>>> >> > and mine is echo "PCI" > /sys/bus/pci/devices/PCI/driver/unbind
>>> >> >
>>> >> > Obviously one looks up which driver is being used by the PCI id, but
>>> >> > how do I look up which driver my PCI card is using?
>>> >> >
>>> >> > Thanks,
>>> >> >
>>> >> > James.
>>> >> >
>>> >>
>>> >> Hi,
>>> >>
>>> >> OK, adding the fourth line does nothing, changing the second line to
>>> >> "driver" rather than "device" does nothing, including in combination
>>> >> with fourth line there/not there.
>>> >
>>> > Yep, the last line is just removing the id from pci-stub, it doesn't
>>> > change anything about devices that are already bound to it.  driver vs
>>> > device are just different ways to get to the same thing.
>>> >
>>> >> So I'm still stuck, can anybody else help?
>>> >> Perhaps point me to a guide on how to compile the latest qemu-kvm
>>> >> against my kernel?
>>> >
>>> > I don't know why you're getting -EBUSY for this device, but maybe we can
>>> > start from a clean slate and see if it helps.  Here's what I would
>>> > suggest:
>>> >
>>> > echo "0000:08:06.0" > /sys/bus/pci/devices/0000:08:06.0/driver/unbind
>>> > echo "0000:08:06.1" > /sys/bus/pci/devices/0000:08:06.1/driver/unbind
>>> > echo "0000:08:06.2" > /sys/bus/pci/devices/0000:08:06.2/driver/unbind
>>> > echo "0000:08:0e.0" > /sys/bus/pci/devices/0000:08:0e.0/driver/unbind
>>> >
>>> > Note we have to knock out the firewire because it shares an interrupt
>>> > with the ehci device you're trying to assign.  We want to remove the USB
>>> > controller entirely from the host.  Your dmesg indicates the host is
>>> > still seeing the device via the uhci ports, and isn't happy about it.
>>> > You can ignore pci-stub for the moment, it's just a way to keep drivers
>>> > from claiming the device, it's not required for device assignment.  Now,
>>> > instead of only trying to assign the ehci, let's move the whole usb
>>> > controller to the guest:
>>> >
>>> > -device pci-assign,host=08:06.0,addr=5.0 \
>>> > -device pci-assign,host=08:06.1,addr=5.1 \
>>> > -device pci-assign,host=08:06.2,addr=5.2
>>> >
>>> > (slot 5 on the guest is arbitrary, pick something else if you need to)
>>> > If that works, then you can bind all those devices to pci-stub and it
>>> > should still work.
>>> >
>>> > Alex
>>>
>>> Hi,
>>>
>>> Sorry about the slow reply, I hosed all of my PCs fiddling with
>>> compiling the latest qemu, took me a while to put it all back together
>>> again in between work!
>>>
>>> I'm afraid I use virtmanager, although I guess using the "add pci
>>> device" function is the same as -device pci-assign? It does seem to
>>> add it to the command line that gets written out to the log files in
>>> /var/log/libvirt/qemu.
>>>
>>> Nevertheless, I've tried that and still not luck, the log output is
>>> similar, with one extra line:
>>>
>>> http://pastebin.com/MJ6aqjNq
>>
>> You actually ended up with:
>>
>> -device pci-assign,host=08:06.0,id=hostdev0,configfd=58,bus=pci.0,addr=0x6 \
>> -device pci-assign,host=08:06.1,id=hostdev1,configfd=59,bus=pci.0,addr=0x7 \
>> -device pci-assign,host=08:06.2,id=hostdev2,configfd=60,bus=pci.0,addr=0x8
>>
>> Which isn't quite what I was suggesting.  You probably have xml that
>> looks like this:
>>
>>    <hostdev mode='subsystem' type='pci' managed='yes'>
>>
>>
>>
>>    </hostdev>
>>    ...
>>
>> Try adding an address line, so you get something more like this:
>>
>>    <hostdev mode='subsystem' type='pci' managed='yes'>
>>
>>
>>
>>
>>    </hostdev>
>>    <hostdev mode='subsystem' type='pci' managed='yes'>
>>
>>
>>
>>
>>    </hostdev>
>>    <hostdev mode='subsystem' type='pci' managed='yes'>
>>
>>
>>
>>
>>    </hostdev>
>>
>>
>>> Using raw in/out ioport access (sysfs - Input/output error)
>>
>> This is just an informational line to let us know whether pci-sysfs
>> supports read/write on the ioport resource files.  If it does, we use
>> those rather than doing raw in/out for access to the device.  This does
>> highlight another potential problem.  Your distro probably doesn't have
>> all the patches in place for non-privileged device assignment, which
>> could be why you're having strange issues.  Check
>> your /etc/libvirt/qemu.conf for the 'user =' and 'group =' lines.  If
>> they're not already, try setting them to 'root', restart libvirtd and
>> see if anything improves.
>>
>>> Here's the dmesg output:
>>> http://pastebin.com/AE1euUN1
>>
>> If still issues after the above, it might be useful to pastbin the
>> entire dmesg so we can make sure the iommu is really on.  Thanks,
>>
>> Alex
>
> Hi,
>
> No such luck I'm afraid.
>
> Here is the original XML:
>
>    <hostdev mode='subsystem' type='pci' managed='yes'>
>
>
>
>      <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
> function='0x0'/>
>    </hostdev>
>    <hostdev mode='subsystem' type='pci' managed='yes'>
>
>
>
>      <address type='pci' domain='0x0000' bus='0x00' slot='0x07'
> function='0x0'/>
>    </hostdev>
>    <hostdev mode='subsystem' type='pci' managed='yes'>
>
>
>
>      <address type='pci' domain='0x0000' bus='0x00' slot='0x08'
> function='0x0'/>
>    </hostdev>
>
> The only difference from your recommended change is the target (I take
> it they are target addresses for the VM?) addresses run:
> 0000:00:06.0
> 0000:00:07.0
> 0000:00:08.0
>
> Instead of:
> 0000:00:06.0
> 0000:00:06.1
> 0000:00:06.2
>
> Regardless, I still changed test.xml to:
> <hostdev mode='subsystem' type='pci' managed='yes'>
>
>
>
>      <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
> function='0x0'/>
>    </hostdev>
>    <hostdev mode='subsystem' type='pci' managed='yes'>
>
>
>
>      <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
> function='0x1'/>
>    </hostdev>
>    <hostdev mode='subsystem' type='pci' managed='yes'>
>
>
>
>      <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
> function='0x2'/>
>    </hostdev>
>
> To no effect.
>
> In qemu.conf, user and group were commented out, I uncommented both
> and they were both already set to root.
>
> After both a restart of libvirt-bin and the pc itself, no change.
>
> Finally, here is the very latest dmesg:
> http://pastebin.com/9HE61K62
>
> Does anybody know the debug kernel switches for iommu?
>
> Many Thanks,
>
> James.
>

Hi,

A ray of sunshine (ish)

I can apparently pass through this device:

00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) (rev 40)
Subsystem: Giga-byte Technology Device a102
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=slow >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 32, Cache Line Size: 64 bytes
Interrupt: pin ? routed to IRQ 16
Region 0: Memory at fdff4000 (64-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: HDA Intel
Kernel modules: snd-hda-intel

From test.log:

2011-02-21 22:40:58.888: starting up
LC_ALL=C PATH=/usr/local/sbin:/usr/local/bin:/usr/bin:/usr/sbin:/sbin:/bin
QEMU_AUDIO_DRV=none /usr/bin/kvm -S -M pc-0.14 -enable-kvm -m 512 -smp
3,sockets=3,cores=1,threads=1 -name test -uuid
307bfcd2-9dec-29b7-1b4d-c46cd9d7cdbc -nodefconfig -nodefaults -chardev
socket,id=charmonitor,path=/var/lib/libvirt/qemu/test.monitor,server,nowait
-mon chardev=charmonitor,id=monitor,mode=readline -rtc base=utc -boot
c -drive file=/var/lib/libvirt/images/test.img,if=none,id=drive-virtio-disk0,boot=on,format=raw
-device virtio-blk-pci,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0
-drive file=/home/james/ubuntu_10.10_x86.iso,if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw
-device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0
-netdev tap,fd=59,id=hostnet0 -device
virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:7d:32:7c,bus=pci.0,addr=0x3
-chardev pty,id=charserial0 -device
isa-serial,chardev=charserial0,id=serial0 -usb -vnc 127.0.0.1:1 -vga
cirrus -device pci-assign,host=00:14.2,id=hostdev0,configfd=60,bus=pci.0,addr=0x6
-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5
char device redirected to /dev/pts/1
kvm: -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:7d:32:7c,bus=pci.0,addr=0x3:
pci_add_option_rom: failed to find romfile "pxe-virtio.bin"
2011-02-21 22:41:48.090: shutting down

Specifically: -device
pci-assign,host=00:14.2,id=hostdev0,configfd=60,bus=pci.0,addr=0x6

Unfortunately I can't get it to boot an ISO through virtmanager! ><
Well, not without deleting the VM and recreating it again.
I shall try getting the latest virt-manager.

Regards,

James.