Re: Possible bug with pass-through hot-plug?

[Simon Horman <horms@verge.net.au>]

Hi Tom,

On Thu, Oct 08, 2009 at 03:55:21PM +0200, Tom Rotenberg wrote:
> The qemu xen i tested today, (which aslo doesn't work), is:
> --------------------------------------------------------------
> commit a05958b6e32f1748ea70b1efca13394956c0698b
> Author: Ian Jackson <ian.jackson@eu.citrix.com>
> Date:   Wed Oct 7 15:57:18 2009 +0100
> 
>     block: Clean up after deleting BHs
> --------------------------------------------------------------
> 
> Here are the log results you wanted (without my change):
> 
> dm-command: hot insert pass-through pci dev
> insert_to_pci_devfn: bdf_slt="0000:00:1b.0@100"

The 100 is the problem. If you are using slot 1b (and function 0)
then it should be:

	PCI_DEVFN(1b,0) = (1b << 3) + 0) = d8

Slot values with bit 9 set (that is >= 0x100) are used to tell
qemu-xen to choose a slot. Is your pass-through device showing
up in the guest at all, for instance in some low virtual slot like 4?

The 100 should be originating from parse_pci_name_extended() which
is called by xm for hot-plug and xend for boot-time assignment.
Instrumenting the callers of that function might help to shed some light
on the problem.

Lastly, could you post the syntax you are using to pass-through
the device? Is possible that my tests aren't covering your case.