Re: [PATCH] x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes
From: Borislav Petkov
Date: Thu Feb 27 2020 - 13:01:10 EST
On Wed, Feb 26, 2020 at 04:16:13PM -0800, Jacob Keller wrote:
> I tested this and it resolves my report! Thanks for a timely fix.
Adding your Tested-by.
> I agree with the analysis. Perhaps it would make sense in the long term
> to find a solution where get_cpu_cap can remember what was cleared for
> each CPU and restore those? It already does this using the global
> variables...
get_cpu_cap() remembers if you use setup_force_cpu_cap() but I agree
that that whole feature bit handling is a bit, hm, "strange". It had its
raisins.
FWIW, we had started cleaning those up but then the security nightmares
happened so on the backburner it went...
Thx.
--
Regards/Gruss,
Boris.
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