Re: [PATCH 5/7] arm64: KVM: Make ICC_SRE_EL1 access return the configured SRE value

[Christoffer Dall <christoffer.dall@linaro.org>]

On Mon, May 23, 2016 at 01:37:01PM +0100, Marc Zyngier wrote:
> When we trap ICC_SRE_EL1, we handle it as RAZ/WI. It would be
> more correct to actual make it RO, and return the configured
> value when read.
> 
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> ---

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>

>  arch/arm64/kvm/sys_regs.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
> index 7bbe3ff..a57d650 100644
> --- a/arch/arm64/kvm/sys_regs.c
> +++ b/arch/arm64/kvm/sys_regs.c
> @@ -134,6 +134,17 @@ static bool access_gic_sgi(struct kvm_vcpu *vcpu,
>  	return true;
>  }
>  
> +static bool access_gic_sre(struct kvm_vcpu *vcpu,
> +			   struct sys_reg_params *p,
> +			   const struct sys_reg_desc *r)
> +{
> +	if (p->is_write)
> +		return ignore_write(vcpu, p);
> +
> +	p->regval = vcpu->arch.vgic_cpu.vgic_v3.vgic_sre;
> +	return true;
> +}
> +
>  static bool trap_raz_wi(struct kvm_vcpu *vcpu,
>  			struct sys_reg_params *p,
>  			const struct sys_reg_desc *r)
> @@ -958,7 +969,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
>  	  access_gic_sgi },
>  	/* ICC_SRE_EL1 */
>  	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b1100), Op2(0b101),
> -	  trap_raz_wi },
> +	  access_gic_sre },
>  
>  	/* CONTEXTIDR_EL1 */
>  	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b001),
> -- 
> 2.1.4
>