Subject: [PATCH v2 16/17] arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit

From: [email-masked] (Christoffer Dall)
Date: Thu, 3 Mar 2016 20:21:50 +0100

On Wed, Feb 17, 2016 at 04:40:48PM +0000, Marc Zyngier wrote:
> So far, we're always writing all possible LRs, setting the empty
> ones with a zero value. This is obvious doing a low of work for
> nothing, and we're better off clearing those we've actually
> dirtied on the exit path (it is very rare to inject more than one
> interrupt at a time anyway).
> 
> Signed-off-by: Marc Zyngier <[email-masked]>
> ---
>  arch/arm64/kvm/hyp/vgic-v3-sr.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c
> index ff67296..5f12c57 100644
> --- a/arch/arm64/kvm/hyp/vgic-v3-sr.c
> +++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c
> @@ -199,6 +199,7 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
>  			}
>  
>  			cpu_if->vgic_lr[i] = __gic_v3_get_lr(i);
> +			__gic_v3_set_lr(0, i);
>  		}
>  
>  		switch (nr_pri_bits) {
> @@ -296,12 +297,10 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
>  		}
>  		 	                           
>  		for (i = 0; i <= max_lr_idx; i++) {
> -			val = 0;
> -
> -			if (live_lrs & (1 << i))
> -				val = cpu_if->vgic_lr[i];
> +			if (!(live_lrs & (1 << i)))
> +				continue;
>  
> -			__gic_v3_set_lr(val, i);
> +			__gic_v3_set_lr(cpu_if->vgic_lr[i], i);
>  		}
>  	}
>  
> -- 
> 2.1.4
> 

same comment here with initializing the LRs, but otherwise:

Reviewed-by: Christoffer Dall <[email-masked]>