Re: [PATCH 1/2] KVM: x86: set TMR when the interrupt is accepted

From: Steve Rutherford
Date: Wed Sep 02 2015 - 18:38:40 EST


On Thu, Aug 13, 2015 at 09:31:48AM +0200, Paolo Bonzini wrote:
Pinging this thread.

Should I put together a patch to make split irqchip work properly with the old TMR behavior?

>
>
> On 13/08/2015 08:35, Zhang, Yang Z wrote:
> >> You may be right. It is safe if no future hardware plans to use
> >> it. Let me check with our hardware team to see whether it will be
> >> used or not in future.
> >
> > After checking with Jun, there is no guarantee that the guest running
> > on another CPU will operate properly if hypervisor modify the vTMR
> > from another CPU. So the hypervisor should not to do it.
>
> I guess I can cause a vmexit on level-triggered interrupts, it's not a
> big deal, but no weasel words, please.
>
> What's going to break, and where is it documented?
>
> Paolo
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
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/