Re: [PATCH] KVM: selftests: Skip tests that require EPT when it is not available

[Paolo Bonzini <pbonzini@redhat.com>]

On 9/26/22 19:14, David Matlack wrote:
> Skip selftests that require EPT support in the VM when it is not
> available. For example, if running on a machine where kvm_intel.ept=N
> since KVM does not offer EPT support to guests if EPT is not supported
> on the host.
> 
> This commit causes vmx_dirty_log_test to be skipped instead of failing
> on hosts where kvm_intel.ept=N.
> 
> Signed-off-by: David Matlack <dmatlack@google.com>
> ---
>   .../selftests/kvm/include/x86_64/vmx.h        |  1 +
>   tools/testing/selftests/kvm/lib/x86_64/vmx.c  | 20 +++++++++++++++++++
>   2 files changed, 21 insertions(+)
> 
> diff --git a/tools/testing/selftests/kvm/include/x86_64/vmx.h b/tools/testing/selftests/kvm/include/x86_64/vmx.h
> index 99fa1410964c..790c6d1ecb34 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/vmx.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/vmx.h
> @@ -617,6 +617,7 @@ void nested_map_memslot(struct vmx_pages *vmx, struct kvm_vm *vm,
>   			uint32_t memslot);
>   void nested_identity_map_1g(struct vmx_pages *vmx, struct kvm_vm *vm,
>   			    uint64_t addr, uint64_t size);
> +bool kvm_vm_has_ept(struct kvm_vm *vm);
>   void prepare_eptp(struct vmx_pages *vmx, struct kvm_vm *vm,
>   		  uint32_t eptp_memslot);
>   void prepare_virtualize_apic_accesses(struct vmx_pages *vmx, struct kvm_vm *vm);
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/vmx.c b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
> index 80a568c439b8..d21049c38fc5 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/vmx.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
> @@ -5,6 +5,8 @@
>    * Copyright (C) 2018, Google LLC.
>    */
>   
> +#include <asm/msr-index.h>
> +
>   #include "test_util.h"
>   #include "kvm_util.h"
>   #include "processor.h"
> @@ -542,9 +544,27 @@ void nested_identity_map_1g(struct vmx_pages *vmx, struct kvm_vm *vm,
>   	__nested_map(vmx, vm, addr, addr, size, PG_LEVEL_1G);
>   }
>   
> +bool kvm_vm_has_ept(struct kvm_vm *vm)
> +{
> +	struct kvm_vcpu *vcpu;
> +	uint64_t ctrl;
> +
> +	vcpu = list_first_entry(&vm->vcpus, struct kvm_vcpu, list);
> +	TEST_ASSERT(vcpu, "Cannot determine EPT support without vCPUs.\n");
> +
> +	ctrl = vcpu_get_msr(vcpu, MSR_IA32_VMX_TRUE_PROCBASED_CTLS) >> 32;
> +	if (!(ctrl & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS))
> +		return false;
> +
> +	ctrl = vcpu_get_msr(vcpu, MSR_IA32_VMX_PROCBASED_CTLS2) >> 32;
> +	return ctrl & SECONDARY_EXEC_ENABLE_EPT;
> +}
> +
>   void prepare_eptp(struct vmx_pages *vmx, struct kvm_vm *vm,
>   		  uint32_t eptp_memslot)
>   {
> +	TEST_REQUIRE(kvm_vm_has_ept(vm));
> +
>   	vmx->eptp = (void *)vm_vaddr_alloc_page(vm);
>   	vmx->eptp_hva = addr_gva2hva(vm, (uintptr_t)vmx->eptp);
>   	vmx->eptp_gpa = addr_gva2gpa(vm, (uintptr_t)vmx->eptp);
> 
> base-commit: 372d07084593dc7a399bf9bee815711b1fb1bcf2
> prerequisite-patch-id: 2e3661ba8856c29b769499bac525b6943d9284b8
> prerequisite-patch-id: 93031262de7b1f7fab1ad31ea5d6ef812c139179

Queued for 6.0, thanks.

Paolo