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

[Paolo Bonzini]

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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/