Re: [PATCH v2 1/2] KVM: selftests: SEV: Verify unsupported VM types are rejected at creation

[Sean Christopherson <seanjc@google.com>]

On Thu, Jul 09, 2026, Hemanth Selam wrote:
> @@ -73,19 +74,34 @@ static void test_init2_invalid(unsigned long vm_type, struct kvm_sev_init *init,
>  	kvm_vm_free(vm);
>  }
>  
> +static void test_create_invalid_type(unsigned long vm_type, const char *msg)
> +{
> +	int fd = __kvm_ioctl(kvm_fd, KVM_CREATE_VM, (void *)vm_type);
> +	int err = errno;
> +
> +	/* Clean up before asserting; TEST_ASSERT() aborts on failure. */

Literally every test relies on the kernel to clean up fds on an early exit.  I
see no reason for this to behave differently.

Also, Sashiko was wrong.  If KVM_CREATE_VM fails with something other than EINVAL,
the assert will NOT fire, but fd will be < 0.

> +	if (fd >= 0)
> +		close(fd);
> +
> +	TEST_ASSERT(fd < 0 && err == EINVAL,
> +		    "KVM_CREATE_VM should reject unsupported type (%s), got fd=%d errno=%d",
> +		    msg, fd, err);

test_assert logs the errno, no need to spit it out here as well.

> +}
> +
>  void test_vm_types(void)
>  {
>  	test_init2(KVM_X86_SEV_VM, &(struct kvm_sev_init){});
>  
> -	/*
> -	 * TODO: check that unsupported types cannot be created.  Probably
> -	 * a separate selftest.

Heh, I agree with the comment: put this in a separate selftest.  This doesn't
have anything to do with KVM_SEV_INIT2, and in fact doesn't even have anyting to
do with SEV+ or even x86.  E.g. add a kvm_vm_types_test that attempts to create
all possible VM types, and asserts success/failure based on the output from
kvm_check_cap(KVM_CAP_VM_TYPES).