[MODERATED] Re: [patch 07/11] [PATCH v2 07/10] Linux Patch #7

[Borislav Petkov <bp@suse.de>]

On Sat, Apr 21, 2018 at 06:13:16PM -0400, speck for Jon Masters wrote:
> I propose keeping either the x86 CPU capability "Memory Disambiguation"
> (as you said, via the string in the define). But only for what is
> displayed in /proc/cpuinfo.

Actually, thinking about this more, we don't need to have any strings
in /proc/cpuinfo denoting the CPU has the memory disambiguation feature
because we only want to know whether we can *disable* the MD. And that
we can do only on a subset of CPUs. IOW, there are other CPU models
which *might* have MD but where MD cannot be disabled... yet.

So having MD or whatever string we agree upon in /proc/cpuinfo will be a
lie.

IOW, we only need two flags:

X86_FEATURE_STBUF_BYPASS
X86_FEATURE_STBUF_BYPASS_MITIGATE

or whatever those are going to be called and neither of the two should
be visible in /proc/cpuinfo.

SSB state will be visible in /sys/devices/system/cpu/vulnerabilities/

Yap, I think that should work.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
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