Re: PCI passthru with Xen 3.0, NetBSD 5.1 dom0, Linux domU

[Julien Oster <julien%julien-oster.de@localhost>]

On Wed, Jun 8, 2011 at 12:18, Manuel Bouyer <bouyer%antioche.eu.org@localhost> 
wrote:
> Yes, if the guest has a chance to shutdown. a 'xm destroy' will leave
> the device fully enabled.

It happens after a clean shutdown of the guest OS:

Deactivating swap...done.
Will now halt.
[  233.902131] xenbus_dev_shutdown: device/console/0: Initialising !=
Connected, skipping
[  238.904064] xenbus_dev_shutdown: device/pci/0 timeout closing device
[  238.947799] System halted.

After that last line, my ssh sessions to dom0 are gone. The
"device/pci/0 timeout" line might be relevant, though?

(By the way, Konrad: with 2.6.39 the TX timeout messages I had before
have indeed disappeared)

> there isn't much that can be done at the backend level. Disabling a device
> is usually a device-specific thing which can only be done by the
> device's driver. A generic driver like pciback can't do much ...

Interesting: if I remove the ath9k module in Linux before shutting
down, no hang occurs. The device/pci/0 timeout message stays, though.


>> The card is also the only device on bus 4 and pin21 isn't attached to
>> any other busses (keep in mind that I currently know next to nothing
>> about PCI, though).
> You just need to check if "ioapic0 pin 21" is used by other
> devices (grep "ioapic0 pin 21" /var/run/dmesg.boot).

That's what I did. But here's the output:

green-jelly:~% grep 'pin 21' /var/run/dmesg.boot
ioapic0: pin 21 attached to pci4 device 0 INT_A (type 0<type=0> flags
f<pol=3=Act Lo,trig=3=Level>)
ioapic0: pin 21 attached to pci4 device 1 INT_B (type 0<type=0> flags
f<pol=3=Act Lo,trig=3=Level>)
ioapic0: pin 21 attached to pci4 device 3 INT_C (type 0<type=0> flags
f<pol=3=Act Lo,trig=3=Level>)
ioapic0: pin 21 attached to pci4 device 5 INT_D (type 0<type=0> flags
f<pol=3=Act Lo,trig=3=Level>)
pciback0: interrupting at ioapic0 pin 21, event channel 9


Cheers,
Julien