Re: [PATCH v2 1/5] KVM: arm64: Reject the GICv5 CPU interface hypercalls under pKVM

[Suzuki K Poulose <suzuki.poulose@arm.com>]

On 11/10/2026 15:36, Fuad Tabba wrote:
> __vgic_v5_save_apr() and __vgic_v5_restore_vmcr_apr() remain callable
> once pKVM has finalised. pKVM never registers a GICv5 vgic, so neither
> has a valid caller in protected mode, and on a GICv3 machine both reach
> a register that is UNDEFINED at EL2 and panic the hypervisor.
> 
> Move both into the band the dispatcher rejects once pKVM has finalised.
> 
> Fixes: af325e87af5da ("KVM: arm64: gic-v5: Add vgic-v5 save/restore hyp interface")
> Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
> ---
>   arch/arm64/include/asm/kvm_asm.h   | 4 ++--
>   arch/arm64/kvm/hyp/nvhe/hyp-main.c | 4 ++--
>   2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
> index e5b92ac09e69e..ea319c496bb26 100644
> --- a/arch/arm64/include/asm/kvm_asm.h
> +++ b/arch/arm64/include/asm/kvm_asm.h
> @@ -62,6 +62,8 @@ enum __kvm_host_smccc_func {
>   	__KVM_HOST_SMCCC_FUNC___kvm_enable_ssbs,
>   	__KVM_HOST_SMCCC_FUNC___vgic_v3_init_lrs,
>   	__KVM_HOST_SMCCC_FUNC___vgic_v3_get_gic_config,
> +	__KVM_HOST_SMCCC_FUNC___vgic_v5_save_apr,
> +	__KVM_HOST_SMCCC_FUNC___vgic_v5_restore_vmcr_apr,
>   
>   	MARKER(__KVM_HOST_SMCCC_FUNC_MIN_PKVM),
>   

Any calls above are rejected after pKVM is initialized, so the calls are 
indeed rejected.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>