Re: PCI Express MMCONFIG and BIOS Bug messages..

[Chuck Ebbert <cebbert@redhat.com>]

Robert Hancock wrote:
> I've seen a lot of systems (including brand new Xeon-based servers from
> IBM and HP) that output messages on boot like:
> 
> PCI: BIOS Bug: MCFG area at f0000000 is not E820-reserved
> PCI: Not using MMCONFIG.
> 
> 
> So Microsoft is explicitly telling the BIOS developers that there is no
> need to reserve the MMCONFIG space in the E820 table because Windows
> doesn't care. On that basis it doesn't seem like a valid check to
> require it to be so reserved, then.
> 
> Really, I think we should be basing this check on whether the
> corresponding memory range is reserved in the ACPI resources, like
> Windows expects. This does require putting more fingers into ACPI from
> this early boot stage, though..
> 

Intel had posted patches to do exactly that, but they were rejected.
I don't remember why now...