Re: [Qemu-devel] "usb: uhci: Look up queue by address, not token"

[Gerd Hoffmann <kraxel@redhat.com>]

On 11/15/12 16:40, Jan Kiszka wrote:
> Hi Hans,
> 
> On 2012-11-15 16:19, Hans de Goede wrote:
>> Hi Jan,
>>
>> I just saw your $subject patch in Gerd's usb-next tree, and I've a question
>> about it. The token should be enough to uniquely identify a device + ep,
>> and unless a guest uses multiple qhs for a singe ep, that _should_ be enough.
> 
> But what disallows that the guest issues multiple requests (QH + series
> of TDs) for a single endpoint? I'm not finding any trace in the spec
> that disallows this. And my special guest is stumbling over that
> limitation in QEMU.

The order which the TDs from the two QHs are filled is undefined I
think, so why a guest would do that?

I guess I'll push back the patch in the queue and don't include it into
the 1.3 pull req until this is sorted.

cheers,
  Gerd