Re: [PATCH 2/2] KVM: arm64: selftests: Test empty SMCCC filter range at base 0

[Fuad Tabba]

On Sat, 29 Aug 2026 at 06:50, Karl Mehltretter <kmehltretter@xxxxxxxxx> wrote:
>
> test_invalid_nr_functions() only checks an empty range at
> PSCI_0_2_FN64_CPU_ON, which KVM's end < start check happens to catch.
> It never exercised base 0, where the inclusive end wraps to U32_MAX
> instead.
>
> Add the base 0 case. Without the preceding fix it fails with EEXIST.
>
> Assisted-by: LLM
> Signed-off-by: Karl Mehltretter <kmehltretter@xxxxxxxxx>

Same nit as before.

Reviewed-by: Fuad Tabba <fuad.tabba@xxxxxxxxx>
Tested-by: Fuad Tabba < fuad.tabba@xxxxxxxxx>

Cheers,
/fuad

> ---
>  tools/testing/selftests/kvm/arm64/smccc_filter.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/tools/testing/selftests/kvm/arm64/smccc_filter.c b/tools/testing/selftests/kvm/arm64/smccc_filter.c
> index 21e41880261b..a41ed3e016ba 100644
> --- a/tools/testing/selftests/kvm/arm64/smccc_filter.c
> +++ b/tools/testing/selftests/kvm/arm64/smccc_filter.c
> @@ -140,6 +140,10 @@ static void test_invalid_nr_functions(void)
>         TEST_ASSERT(r < 0 && errno == EINVAL,
>                     "Attempt to filter 0 functions should return EINVAL");
>
> +       r = __set_smccc_filter(vm, 0, 0, KVM_SMCCC_FILTER_DENY);
> +       TEST_ASSERT(r < 0 && errno == EINVAL,
> +                   "Attempt to filter 0 functions at base 0 should return EINVAL");
> +
>         kvm_vm_free(vm);
>  }
>
> --
> 2.39.5 (Apple Git-154)
>