Re: [PATCH 15/31] KVM: arm64: vgic-v3: Add ICV_AP1Rn_EL1 handler

Auger Eric
2017-05-30T07:48:24Z

H Marc,

On 03/05/2017 12:45, Marc Zyngier wrote:
> Add a handler for reading/writing the guest's view of the ICV_AP1Rn_EL1
> registers. We just map them to the corresponding ICH_AP1Rn_EL2 registers.
>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> ---
> arch/arm64/include/asm/sysreg.h | 1 +
> virt/kvm/arm/hyp/vgic-v3-sr.c | 94 +++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 95 insertions(+)
>
> diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> index 15c142ce991c..aad46b8eea5e 100644
> --- a/arch/arm64/include/asm/sysreg.h
> +++ b/arch/arm64/include/asm/sysreg.h
> @@ -180,6 +180,7 @@
>
> #define SYS_VBAR_EL1 sys_reg(3, 0, 12, 0, 0)
>
> +#define SYS_ICC_AP1Rn_EL1(n) sys_reg(3, 0, 12, 9, n)
> #define SYS_ICC_DIR_EL1 sys_reg(3, 0, 12, 11, 1)
> #define SYS_ICC_SGI1R_EL1 sys_reg(3, 0, 12, 11, 5)
> #define SYS_ICC_IAR1_EL1 sys_reg(3, 0, 12, 12, 0)
> diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
> index a76351b3ad66..b6803989da1f 100644
> --- a/virt/kvm/arm/hyp/vgic-v3-sr.c
> +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
> @@ -684,6 +684,76 @@ static void __hyp_text __vgic_v3_write_bpr1(struct kvm_vcpu *vcpu, u32 vmcr, int
> __vgic_v3_write_vmcr(vmcr);
> }
>
> +static void __hyp_text __vgic_v3_read_apxrn(struct kvm_vcpu *vcpu, int rt, int n)
Shouldn't you test somewhere that n is correct given the number of
implemented priority bits
> +{
> + u32 val;
> +
> + if (!__vgic_v3_get_group(vcpu))
I don't really get how an access to AP1Rn can end up in AP0Rn. I am not
able to find any related description in the spec?

Thanks

Eric
> + val = __vgic_v3_read_ap0rn(n);

> + else
> + val = __vgic_v3_read_ap1rn(n);
> +
> + vcpu_set_reg(vcpu, rt, val);
> +}
> +
> +static void __hyp_text __vgic_v3_write_apxrn(struct kvm_vcpu *vcpu, int rt, int n)
> +{
> + u32 val = vcpu_get_reg(vcpu, rt);
> +
> + if (!__vgic_v3_get_group(vcpu))
> + __vgic_v3_write_ap0rn(val, n);
> + else
> + __vgic_v3_write_ap1rn(val, n);
> +}
> +
> +static void __hyp_text __vgic_v3_read_apxr0(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_read_apxrn(vcpu, rt, 0);
> +}
> +
> +static void __hyp_text __vgic_v3_read_apxr1(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_read_apxrn(vcpu, rt, 1);
> +}
> +
> +static void __hyp_text __vgic_v3_read_apxr2(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_read_apxrn(vcpu, rt, 2);
> +}
> +
> +static void __hyp_text __vgic_v3_read_apxr3(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_read_apxrn(vcpu, rt, 3);
> +}
> +
> +static void __hyp_text __vgic_v3_write_apxr0(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_write_apxrn(vcpu, rt, 0);
> +}
> +
> +static void __hyp_text __vgic_v3_write_apxr1(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_write_apxrn(vcpu, rt, 1);
> +}
> +
> +static void __hyp_text __vgic_v3_write_apxr2(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_write_apxrn(vcpu, rt, 2);
> +}
> +
> +static void __hyp_text __vgic_v3_write_apxr3(struct kvm_vcpu *vcpu,
> + u32 vmcr, int rt)
> +{
> + __vgic_v3_write_apxrn(vcpu, rt, 3);
> +}
> +
> int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
> {
> int rt = kvm_vcpu_sys_get_rt(vcpu);
> @@ -722,6 +792,30 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
> else
> fn = __vgic_v3_write_bpr1;
> break;
> + case SYS_ICC_AP1Rn_EL1(0):
> + if (is_read)
> + fn = __vgic_v3_read_apxr0;
> + else
> + fn = __vgic_v3_write_apxr0;
> + break;
> + case SYS_ICC_AP1Rn_EL1(1):
> + if (is_read)
> + fn = __vgic_v3_read_apxr1;
> + else
> + fn = __vgic_v3_write_apxr1;
> + break;
> + case SYS_ICC_AP1Rn_EL1(2):
> + if (is_read)
> + fn = __vgic_v3_read_apxr2;
> + else
> + fn = __vgic_v3_write_apxr2;
> + break;
> + case SYS_ICC_AP1Rn_EL1(3):
> + if (is_read)
> + fn = __vgic_v3_read_apxr3;
> + else
> + fn = __vgic_v3_write_apxr3;
> + break;
> default:
> return 0;
> }
>