Re: [PATCH RFC] function probe_roms accessing improper addresses

From: H. Peter Anvin
Date: Fri Oct 19 2012 - 11:37:54 EST


On 10/19/2012 08:30 AM, Matthew Garrett wrote:
I don't think DMI checking is going to work, since (a) as you say,
there's a risk that the ID will inadvertantly change over the lifecycle
of the machine, and (b) there may be other machines. So if it's not
possible to handle this by catching the MCE, I think we have two
options:

1) Declare that any x86 hardware supported by Linux *must* support
probing in this address region

2) Don't call probe_roms() by default, but leave it up to the graphics
drivers. If they can get the rom by any other means then don't call it.


Honestly, (1) is the proper option. Hearing that this is a prototype, I would like to say "fix your bloody hardware/firmware"...

The legacy region is special and will always be special, and so any attempts at making it non-special is a losing battle.

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

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