Re: [Xen-users] [BUG] PCI passtrough causes driver crash in DomU (Xen 4.3, Linux kernel 3.12)

[Jonas Meurer <jonas@freesources.org>]

Am 07.03.2014 13:04, schrieb Jonas Meurer:
> Am 07.03.2014 12:54, schrieb Jonas Meurer:
>> as already written to xen-users a few days ago, I've troubles using pci
>> passthrough for an Intel 82574L ethernet device (kernel module e1000e).
>> The device is passed through by xen-pciback, and can be seen by 'lspci'
>> inside the DomU. Still, the corresponding network interface doesn't
>> appear in /proc/net/dev and even more striking, the DomU kernel driver
>> crashes with a traceback.
>>
>> All this happens on a Debian/Jessie Dom0 with Xen 4.3 and Linux kernel
>> 3.12. The DomU in question has a similar Debian/Jessie setup.
>>
>> I searched the archives for similar issues and found the following
>> thread from October 2013 that describes a similar issue starting with
>> Linux kernel 3.8:
>> http://thread.gmane.org/gmane.comp.emulators.xen.user/80672
> 
> Just a quick follow-up: After some further searching I found the
> following thread:
> http://thread.gmane.org/gmane.comp.emulators.xen.user/80176
> 
> In this thread, Ian Campbell suggests to disable MSI for the guest, and
> the submitter replies that it fixed the issue for him. So indeed it
> seems to me like MSI in DomU is the cause for trouble here. I'll give
> the suggested workaround a try within the next days and report back if
> it works for me as well.

I can confirm now, that pci=nomsi argument to kernel commandline in DomU
fixes/workarounds the described issue.

In another mail to xen-devel, Konrad Rzeszutek Wilk mentioned that the
bug got fixed in Linux kernel 3.14. I'll give that kernel a try and
report back as soon as it's available in Debian/experimental.

Kind regards,
 jonas