Re: [PATCH 2/2] virtio: replace arch_has_restricted_virtio_memory_access()

Juergen Gross
2022-04-27T12:45:38Z

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On 27.04.22 14:26, Borislav Petkov wrote:
> On Wed, Apr 27, 2022 at 08:40:08AM +0200, Juergen Gross wrote:
>> I was planning to look at the x86 cpu features to see whether some of
>> those might be candidates to be switched to platform features instead.
>
> I'd say "never touch a running system" unless the platform features are
> of an advantage...

Depends on the use case IMHO.

All features being based on a cpuid bit are no candidates. Same applies
to all features used for alternative handling (assuming we don't want
to expand that to platform features).

I really have no idea whether this will leave any candidates. In case
it does, it might be interesting to switch those in order to save some
per-cpu bits.

Other candidates might be the x86_legacy_features.

Juergen

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