On Thu, Jul 11, 2024, Pratik Rajesh Sampat wrote:
+static void sev_guest_status_assert(struct kvm_vm *vm, uint32_t type) +{
- struct kvm_sev_guest_status status;
- bool cond;
- int ret;
- ret = __vm_sev_ioctl(vm, KVM_SEV_GUEST_STATUS, &status);
- cond = type == KVM_X86_SEV_VM ? !ret : ret;
- TEST_ASSERT(cond,
"KVM_SEV_GUEST_STATUS should fail, invalid VM Type.");+}
+static void test_sev_launch(void *guest_code, uint32_t type, uint64_t policy) +{
- struct kvm_vcpu *vcpu;
- struct kvm_vm *vm;
- struct ucall uc;
- bool cond;
- int ret;
Maybe a block comment here indicating what you're actually doing would be good, because I'm a bit confused.
A policy value of 0 is valid for SEV, so you expect each call to succeed, right? And, actually, for SEV-ES the launch start will succeed, too, but the launch update will fail because LAUNCH_UPDATE_VMSA is not valid for SEV, but then the launch measure should succeed. Is that right? What about the other calls?
Sure, I can do that. Yes for SEV, the policy value of 0 succeeds for everything except when we try to run and we see a KVM_EXIT_IO.
For SEV-ES, with the policy value of 0 - we don't see launch_start succeed. It fails with EIO in this case. Post that all the calls for SEV-ES also fail subsequent to that. I guess the core idea behind this test is to ensure that once the first bad case of launch_start fails, we should see a cascading list of failures.
- vm = vm_sev_create_with_one_vcpu(type, guest_code, &vcpu);
- ret = sev_vm_launch_start(vm, 0);
- cond = type == KVM_X86_SEV_VM ? !ret : ret;
- TEST_ASSERT(cond,
Don't bury the result in a local boolean. It's confusing, and _worse_ for debug as it makes it impossible to see what actually failed (the assert message will simply print "cond", which is useless).
"KVM_SEV_LAUNCH_START should fail, invalid policy.");
This is a blatant lie, because the KVM_X86_SEV_VM case apparently expects success. Similar to Tom's comments about explaing what this code is doing, these assert messages need to explain what the actually expected result it, provide a hint as to _why_ that result is expected, and print the result. As is, this will be unnecessarily difficult to debug if/when it fails.