[SeaBIOS] MP Table corruption

[Dave Frodin]

Kevin,

Comments are inline.

Thanks,
Dave

----- Original Message -----
> From: "Kevin O'Connor" <kevin at koconnor.net>
> To: "Dave Frodin" <dave.frodin at se-eng.com>
> Cc: "seabios" <seabios at seabios.org>
> Sent: Tuesday, October 8, 2013 7:26:25 PM
> Subject: Re: [SeaBIOS] MP Table corruption
> 
> On Tue, Oct 08, 2013 at 05:27:34PM -0500, Dave Frodin wrote:
> > We have a customer that runs a RTOS that uses the MP Tables (rather
> > than ACPI).  They are having an issue with the RTOS not being able
> > to determine certain system interrupt settings from the MP
> > tables. The sent me a MPDiag utility (this may be their own MPDiag
> > utility, I believe I've seen others) that exposes the problem. Using
> > it I was able to determine that the mptable that coreboot generates
> > is getting corrupted somehow by seabios. When I bisected seabios I
> > found that there are several commits that cause the mptable
> > corruption. The first two problem commits are ...
> > 5DBF1732
> > ECA5A947
> 
> This is on coreboot, right?

Yes this is for a coreboot build.

> I don't see a commit ECA5A947 in seabios,

Oooops. I rebased and deleted 5DBF1732 after I bisected down to it.
The 2nd commit that breaks the MPtable is actually A2A86E29.
Sorry for the confusion.

> and I don't see how 5DBF1732 could impact mptable.  I guess it's
> possible that 5DBF1732 could impact the interrupts as we no longer run
> a sipi on all the processors, but I don't think SeaBIOS should have to
> issue a sipi - if that is doing something that impacts the OS then
> coreboot should do it as part of initializing the processors.
> 
> -Kevin
>