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SubjectRe: [PATCH] x86,kvm: move qemu/guest FPU switching out to vcpu_run
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On 15.11.2017 09:34, Paolo Bonzini wrote:
> On 14/11/2017 20:40, David Hildenbrand wrote:
>> I think we should check all get/put_fpu callers if they need
>> preempt_disable().
>>
>> E.g. em_fxrstor() needs disabled preemption as we temporarily
>> save + restore some host register (via fxsave + fxrstor) under some
>> circumstances that are not saved/restored when switching to/back from
>> another process. We should double check.
>
> Rik may correct me, but I believe that you don't need
> preempt_disable/enable because preempt notifiers do this for you.
>

Seems to boil down to what Wanpeng Li asked about preempt notifiers in
response to v2.

--

Thanks,

David / dhildenb

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