Re: [PATCH v13 31/48] KVM: arm64: WARN on injected undef exceptions

Suzuki K Poulose
2026-03-30T10:50:21Z

On 18/03/2026 15:53, Steven Price wrote:
> The RMM doesn't allow injection of a undefined exception into a realm
> guest. Add a WARN to catch if this ever happens.
>
> Signed-off-by: Steven Price <steven.price@arm.com>
> Reviewed-by: Gavin Shan <gshan@redhat.com>

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

> ---
> Changes since v6:
> * if (x) WARN(1, ...) makes no sense, just WARN(x, ...)!
> ---
> arch/arm64/kvm/inject_fault.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c
> index 6492397b73d7..613f223bc7a3 100644
> --- a/arch/arm64/kvm/inject_fault.c
> +++ b/arch/arm64/kvm/inject_fault.c
> @@ -327,6 +327,7 @@ void kvm_inject_size_fault(struct kvm_vcpu *vcpu)
> */
> void kvm_inject_undefined(struct kvm_vcpu *vcpu)
> {
> + WARN(vcpu_is_rec(vcpu), "Unexpected undefined exception injection to REC");
> if (vcpu_el1_is_32bit(vcpu))
> inject_undef32(vcpu);
> else