Re: [PATCH 3/3] KVM: x86: correct mwait and monitor emulation

Paolo Bonzini
2014-06-18T16:44:50Z

Il 18/06/2014 18:43, Bandan Das ha scritto:
>> > mwait and monitor are currently handled as nop. Considering this behavior, they
>> > should still be handled correctly, i.e., check execution conditions and generate
>> > exceptions when required. mwait and monitor may also be executed in real-mode
> Is this necessary ? They are NOPs and kvm prints that out (correctly so) to dmesg.
> Implementing them correctly is a different thing, but adding extra checks for NOPs
> just seems like adding extra cycles.

Raising the correct exception is a good thing, though. The guest is
going to busy wait anyway, it doesn't matter how fast it does that. :)

Paolo