> On Tue, Mar 13, 2018 at 10:39 PM, Theo de Raadt <dera...@openbsd.org> wrote:
> >> According to some sources, Intel and a handful of others have known about 
> >> the
> >> issue since February 2017(!), so perhaps it has already been patched in the
> >> 08Jan2018 BIOS. I too have doubts that to date any processor has been
> >> redesigned to avoid the flaws entirely, but then again...
> >
> > Sure.  A BIOS can change the flag bits.
> >
> > Be nice to know.  Did a BIOS change them?
> 
> I downgraded the bios to try and figure this out. Going back just one
> revision (1/8/2018 to 12/18/2017) causes it to lose the flag and
> -current's MELTDOWN workaround to activate.
> 
> Previous BIOS revision (12/18/2017):
> bcamp@nuc6cayh:~ (OpenBSD 6.3)
> $ cpuid 0x7
> eax = 0x00000000             0    "????"
> ebx = 0x2294e283     580182659    "???""
> ecx = 0x00000000             0    "????"
> edx = 0x00000000             0    "????"
> 
> Newest BIOS revision (1/8/2018):
> bcamp@nuc6cayh:~ (OpenBSD 6.3)
> $  cpuid 0x7
> eax = 0x00000000             0    "????"
> ebx = 0x2294e283     580182659    "???""
> ecx = 0x00000000             0    "????"
> edx = 0x2c000000     738197504    "???,"

Fascinating isn't it?

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