Re: [PATCH] Ability to read the MKTME status from userspace

From: Borislav Petkov
Date: Fri Jun 19 2020 - 12:18:02 EST


On Fri, Jun 19, 2020 at 08:48:47AM -0700, Andy Lutomirski wrote:
> Boris, it wouldnât be totally crazy for cpuinfo to learn to
> distinguish between âyour platform has this feature but Linux
> isnât using itâ and âyour platform doesnât have this feature
> in the first placeâ. And I suppose thereâs this extra silly state
> âyour platform has this feature, but your firmware didnât enable
> itâ. This would be a big job.

Well, I believe all the kernel can do is supply bits of information -
just like MSRs - and depending on the settings of those bits, userspace
can decide what the situation is. For example:

bit 0 - CPUID support
bit 1 - BIOS enabled
bit 2 - quirk applied
bit 3 - microcode fixes present
...

and so on.

It needs a proper definition though and userspace to say, yes, we want
that and that is useful for us.

Where it ends up is then beside the point - /proc/cpuinfo,
/sys/devices/system/cpu, whatever...

--
Regards/Gruss,
Boris.

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