Re: [RFC PATCH] PCI pass-through fixups

[Sheng Yang <sheng@linux.intel.com>]

On Tuesday 07 April 2009 08:02:10 Chris Wright wrote:
> * Alex Williamson (alex.williamson@hp.com) wrote:
> > I'm wondering if we need a spot for device specific fixups for PCI
> > pass-through.  In the example below, I want to expose a single port of
> > an Intel 82571EB quad port copper NIC to a guest.  It works great until
> > I shutdown the guest, at which point the guest e1000e driver knows by
> > the device ID that the NIC is a quad port, and blindly attempts to
> > twiddle some bits on the bridge above it (that doesn't exist).
>
> And what happens?

And the output of DEVICE_ASSIGNMENT_DEBUG=1 may help. And I don't have trouble 
here with another dual/quad port card by Intel, but not 82571EB. 
>
> > Obviously some robustness could be added to the driver, but would it
> > make sense to do something like below and automatically remap these
> > devices to identical single port device IDs?  Thanks,
>
> Sounds quite fragile to me.

Same here... We'd better to know what's happened. (wow, you even know the 
single port ones' device ID... :) )

-- 
regards
Yang, Sheng