From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Wright <chrisw@sous-sol.org>
Subject: Re: [RFC PATCH] PCI pass-through fixups
Date: Mon, 6 Apr 2009 17:02:10 -0700
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Cc: kvm <kvm@vger.kernel.org>, Sheng Yang <sheng@linux.intel.com>
To: Alex Williamson <alex.williamson@hp.com>
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* 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?

> 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.

thanks,
-chris