Re: [tip:x86/setup] x86, setup: "glove box" BIOS calls -- infrastructure

[Pavel Machek <pavel@ucw.cz>]

Hi!

> > Well, difference is that you can defend against arbitrary network 
> > packet, but you can't defend against arbitrarily broken BIOS. If 
> > it loops forever, or overwrites random memory place, we lost...
> 
> We could protect against random memory corruption too, if it ever 
> became a widespread problem: by executing the BIOS call in a virtual 
> machine. (We can probably use the KVM code to properly emulate big 
> real mode, etc.)

We already have problems where bios corrupts low memory area during
suspend/resume. Not sure how KVM helps.

Anyway I do agree with the patches.

> "BIOS people" are operating in a completely different culture. Time 
> to market, hardware workarounds, short-term differentiators, secret 
> bootstrap sequences and code compactness are king in that space. 
> Code quality is dead last in the list. I strongly doubt that given 
> the radically conflicting priorities a reasonable dialogue can be 
> established.

"BIOS people" control stuff like SMM mode. We can workaround some BIOS
problems, but definitely not all of them.

For servers, I guess Linux has enough of market share that we could
certify known-good servers (and maybe warn against known-bad).
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html