Re: [PATCH v2 3/6] KVM: selftests: Test Hyper-V extended hypercall enablement

From: Vitaly Kuznetsov
Date: Tue Nov 22 2022 - 11:03:42 EST


Vipin Sharma <vipinsh@xxxxxxxxxx> writes:

> Test Hyper-V extended hypercall, HV_EXT_CALL_QUERY_CAPABILITIES
> (0x8001), access denied and invalid parameter
> cases.
>
> Access is denied if CPUID.0x40000003.EBX BIT(20) is not set.
> Invalid parameter if call has fast bit set.
>
> Signed-off-by: Vipin Sharma <vipinsh@xxxxxxxxxx>
> ---
> tools/testing/selftests/kvm/include/x86_64/hyperv.h | 4 ++++
> tools/testing/selftests/kvm/x86_64/hyperv_features.c | 9 +++++++++
> 2 files changed, 13 insertions(+)
>
> diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
> index 9218bb5f44bf..8813c1bb74a0 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
> @@ -112,6 +112,7 @@
> #define HV_ACCESS_STATS BIT(8)
> #define HV_DEBUGGING BIT(11)
> #define HV_CPU_MANAGEMENT BIT(12)
> +#define HV_ENABLE_EXTENDED_HYPERCALLS BIT(20)
> #define HV_ISOLATION BIT(22)
>
> /* HYPERV_CPUID_FEATURES.EDX */
> @@ -166,6 +167,9 @@
> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af
> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0
>
> +/* Extended hypercalls */
> +#define HV_EXT_CALL_QUERY_CAPABILITIES 0x8001
> +
> #define HV_FLUSH_ALL_PROCESSORS BIT(0)
> #define HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES BIT(1)
> #define HV_FLUSH_NON_GLOBAL_MAPPINGS_ONLY BIT(2)
> diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_features.c b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
> index 3163c3e8db0a..a5a3146fc299 100644
> --- a/tools/testing/selftests/kvm/x86_64/hyperv_features.c
> +++ b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
> @@ -583,6 +583,15 @@ static void guest_test_hcalls_access(void)
> hcall->expect = HV_STATUS_SUCCESS;
> break;
> case 19:
> + hcall->control = HV_EXT_CALL_QUERY_CAPABILITIES;
> + hcall->expect = HV_STATUS_ACCESS_DENIED;
> + break;
> + case 20:
> + feat->ebx |= HV_ENABLE_EXTENDED_HYPERCALLS;

As I've mentioned on another patch, things look significantly better
after https://lore.kernel.org/kvm/20221013095849.705943-6-vkuznets@xxxxxxxxxx/
cleanup, hope we can have it in soon.

> + hcall->control = HV_EXT_CALL_QUERY_CAPABILITIES | HV_HYPERCALL_FAST_BIT;
> + hcall->expect = HV_STATUS_INVALID_PARAMETER;
> + break;
> + case 21:
> kvm_vm_free(vm);
> return;
> }

--
Vitaly