Re: [Qemu-devel] [PATCH uq/master 2/2] kvm: forward INIT signals coming from the chipset

[Paolo Bonzini]

Il 10/03/2013 15:55, Gleb Natapov ha scritto:
> > > Why not move INIT case from below as is? Vcpu is reset to correct sate
> > > by QEMU just like during system_reset.
> > 
> > APs would not be able to receive SIPIs after executing do_cpu_init,
> > because they would stay in KVM_MP_STATE_RUNNABLE state.
> 
> If APs are in runnable state after reset with in kernel irq chip we
> have a bug somewhere.

Here is where we are resetting the processor.  After clearing
CPU_INTERRUPT_INIT, no matter what else we do (such as resetting the
APIC and CPU), we need to set the mp_state to KVM_MP_STATE_INIT_RECEIVED.

Or if we go with your simpler hypervisor patch, we need to go to either
KVM_MP_STATE_INIT_RECEIVED for APs (wait for SIPI) or
KVM_MP_STATE_SIPI_RECEIVED for the BSP (restart running from the reset
vector).

> Should AP be able to get SIPI without INIT after trigger of INIT# line?

Yes, the effect is the same for an INIT interrupt and the triggering of
INIT#.

Paolo