Re: [PING PATCH v4 23/29] LoongArch: KVM: Implement handle gspr exception

[Paolo Bonzini]

On 3/28/23 14:31, Tianrui Zhao wrote:
> +			case 0xc91:
> +				/* idle GSPR */
> +				er = _kvm_emu_idle(vcpu);
> +				break;

So this is my last remark.  What some other architectures do is change 
vcpu->arch.mp_state when entering an idle state, and at this point all 
calls to KVM_RUN would call the equivalent of _kvm_emu_idle().  This 
requires implementing the KVM_GET_MPSTATE and KVM_SET_MPSTATE ioctls.

This might also be useful if later you want to implement a mechanism 
where vCPUs can pause or resume, for example for multi-vCPU VMs.

You can implement this on top of what you have, but I highly recommend 
that you do it in the first version of what is committed to Linux.

Paolo