Re: AMD errata 793 (CVE-2013-6885) needs a workaround in Linux?

Borislav Petkov
2014-01-14T11:55:57Z

On Tue, Jan 14, 2014 at 09:41:33AM -0200, Henrique de Moraes Holschuh wrote:
> I just got this assigned to amd64-microcode in Debian, but it is something
> that needs to be worked around by the EFI/BIOS and/or the kernel.
>
> Since we all know just how well it pans out to depend on BIOS/EFI updates
> for *anything*, I'm raising the issue here. IMHO looks like it would be
> worthwhile to either set the relevant MSR in the kernel if the BIOS didn't
> do it, or at least warn the user of the need for a BIOS/EFI update...
>
> It is the usual hangs-core type of CPU errata (therefore, the best type
> since it won't cause silent data corruption). gcc-produced code managed to
> trigger it (in DragonFly BSD).

I think this is a different issue than the dragonfly issue. In any case,
if AMD delivers all BIOS with this workaround enabled, we don't need to
do anything. And I asked them about it so we'll have an answer soon, I
hope.

In any case, I'm on it.

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
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