Re: More info on port 80 symptoms on MCP51 machine.

H. Peter Anvin
2007-12-12T21:13:32Z

Alan Cox wrote:
> On Wed, 12 Dec 2007 21:58:25 +0100
> Rene Herman <rene.herman@gmail.com> wrote:
>
>> On 12-12-07 21:26, Rene Herman wrote:
>>
>>> On 12-12-07 21:07, David P. Reed wrote:
>>>> Someone might have an in to nVidia to clarify this, since I don't. In
>>>> any case, the udelay(2) approach seems to be a safe fix for this machine.
>> By the way, _does_ anyone have a contact at nVidia who could clarify? Alan
>> maybe? I'm quite curious what they did...
>
> I don't. Nvidia are not the most open bunch of people on the planet. This
> doesn't appear to be a chipset bug anyway but a firmware one (other
> systems with the same chipset work just fine).
>
> The laptop maker might therefore be a better starting point.

One wonders if it does some SMM trick to capture port 0x80 writes and
attempt to haul them off for debugging; it almost sounds like some kind
of debugging code got let out into the field.

-hpa