Re: K8 Errata #93: adjusting address to a fixup block

[Alexandre Oliva <aoliva@redhat.com>]

On Oct 17, 2004, Andi Kleen <ak@muc.de> wrote:

>> address, so I came up with this patch.  It turned out to make no
>> difference, but it still feels like an improvement to me, since some
>> day we might be resuming from halt into a fix-up block.  Thoughts?

> The code is already ugly enough and handles most of the cases, 
> I don't think it is worth it complicating it even more just
> to handle more corner cases of buggy BIOS.

Fair enough.

> The real fix is to fix your BIOS.

>  	static int warned;
> +	if ((error_code & 16) == 0)
> +		return 0;

> This is dubious because the I/D bit is undefined when NX is disabled
> in EFER (e.g. with noexec=off or when the CPU doesn't support NX)

Aah...  I wasn't aware of that.  Patch withdrawn for sure, then :-)
Thanks for the feedback.

-- 
Alexandre Oliva             http://www.ic.unicamp.br/~oliva/
Red Hat Compiler Engineer   aoliva@{redhat.com, gcc.gnu.org}
Free Software Evangelist  oliva@{lsd.ic.unicamp.br, gnu.org}