Re: Re: follow up to a pciback "pv pci-passthrough co-assigned problem"

[Weidong Han <weidong.han@intel.com>]

mail ignored wrote:
> On Sat, Jan 23, 2010 at 9:58 AM, mail ignored <0.bugs.only.0@gmail.com> wrote:
>   
>> thanks.  i suppose i'll file a bug @ opensuse abt this, and see if
>> they'll put something into code so these changes will 'survive'
>> xen(-tools) updates ...
>>     
>
> cref -> https://bugzilla.novell.com/show_bug.cgi?id=573311
>   

I think this is not a bug. pls note that the devices behind 
PCIe-to-PCI/PCI-x bridge or Conventional PCI bridge can only be 
collectively assigned to a single domain, because the source-id in DMA 
requests is not device's bdf. Pls refer to section 3.6.1 in VT-d spec. 
What's more, FLR is required to make sure the device in a correct status 
before assignment, and some devices need to reset secondary bus to reset 
the device which results in all the devices behind same 
PCIe-to-PCI/PCI-x bridge or Conventional PCI bridge be reset. In your 
case, you need to hide all NICs (04:06.0 and 04:07.0) behind the same 
bridge, and assign them together to a guest. or you can set 
"pci-passthrough-strict-check no" in /etc/xen/xend-config.sxp and 
restart xend to loose the check in xend, but in this way you should be 
aware of potential issues (e.g. assigned device doesn't work).

Regards,
Weidong