Re: [PATCH] KVM: x86: Check for nested events if there is an injectable interrupt

[Paolo Bonzini]

Il 08/07/2014 08:56, Jan Kiszka ha scritto:
> I don't think arch.nmi_pending can flip asynchronously, only in the
> context of the VCPU thread - in contrast to pending IRQ states.

Right, only nmi_queued is changed from other threads.  /me should really 
look at the code instead of going from memory.

> > Jan, what do you think?  Can you run Jailhouse through this patch?
>
> Jailhouse seems fine with it, and it resolves the lockup of nested KVM
> here as well.

Thinking more about it, I think this is the right fix.  Not setting 
KVM_REQ_EVENT in some cases can be an optimization, but it's not 
necessary.  Definitely there are other cases in which KVM_REQ_EVENT is 
set even though no event is pending---most notably during emulation of 
invalid guest state.

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/