Rework platform_info_test to actually handle and verify the expected #GP
on RDMSR when the associated KVM capability is disabled. Currently, the
test _deliberately_ doesn't handle the #GP, and instead lets it escalated
to a triple fault shutdown.
In addition to verifying that KVM generates the correct fault, handling
the #GP will be necessary (without even more shenanigans) when a future
change to the core KVM selftests library configures the IDT and exception
handlers by default (the test subtly relies on the IDT limit being '0').
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
.../selftests/kvm/x86_64/platform_info_test.c | 66 +++++++++----------
1 file changed, 33 insertions(+), 33 deletions(-)
diff --git a/tools/testing/selftests/kvm/x86_64/platform_info_test.c b/tools/testing/selftests/kvm/x86_64/platform_info_test.c
index cdad7e2124c8..6300bb70f028 100644
--- a/tools/testing/selftests/kvm/x86_64/platform_info_test.c
+++ b/tools/testing/selftests/kvm/x86_64/platform_info_test.c
@@ -26,40 +26,18 @@
static void guest_code(void)
{
uint64_t msr_platform_info;
+ uint8_t vector;
- for (;;) {
- msr_platform_info = rdmsr(MSR_PLATFORM_INFO);
- GUEST_ASSERT_EQ(msr_platform_info & MSR_PLATFORM_INFO_MAX_TURBO_RATIO,
- MSR_PLATFORM_INFO_MAX_TURBO_RATIO);
- GUEST_SYNC(0);
- asm volatile ("inc %r11");
- }
-}
+ GUEST_SYNC(true);
+ msr_platform_info = rdmsr(MSR_PLATFORM_INFO);
+ GUEST_ASSERT_EQ(msr_platform_info & MSR_PLATFORM_INFO_MAX_TURBO_RATIO,
+ MSR_PLATFORM_INFO_MAX_TURBO_RATIO);
-static void test_msr_platform_info_enabled(struct kvm_vcpu *vcpu)
-{
- struct ucall uc;
+ GUEST_SYNC(false);
+ vector = rdmsr_safe(MSR_PLATFORM_INFO, &msr_platform_info);
+ GUEST_ASSERT_EQ(vector, GP_VECTOR);
- vm_enable_cap(vcpu->vm, KVM_CAP_MSR_PLATFORM_INFO, true);
- vcpu_run(vcpu);
- TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
-
- switch (get_ucall(vcpu, &uc)) {
- case UCALL_SYNC:
- break;
- case UCALL_ABORT:
- REPORT_GUEST_ASSERT(uc);
- default:
- TEST_FAIL("Unexpected ucall %lu", uc.cmd);
- break;
- }
-}
-
-static void test_msr_platform_info_disabled(struct kvm_vcpu *vcpu)
-{
- vm_enable_cap(vcpu->vm, KVM_CAP_MSR_PLATFORM_INFO, false);
- vcpu_run(vcpu);
- TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_SHUTDOWN);
+ GUEST_DONE();
}
int main(int argc, char *argv[])
@@ -67,16 +45,38 @@ int main(int argc, char *argv[])
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
uint64_t msr_platform_info;
+ struct ucall uc;
TEST_REQUIRE(kvm_has_cap(KVM_CAP_MSR_PLATFORM_INFO));
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
+ vm_init_descriptor_tables(vm);
+ vcpu_init_descriptor_tables(vcpu);
+
msr_platform_info = vcpu_get_msr(vcpu, MSR_PLATFORM_INFO);
vcpu_set_msr(vcpu, MSR_PLATFORM_INFO,
msr_platform_info | MSR_PLATFORM_INFO_MAX_TURBO_RATIO);
- test_msr_platform_info_enabled(vcpu);
- test_msr_platform_info_disabled(vcpu);
+
+ for (;;) {
+ vcpu_run(vcpu);
+ TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
+
+ switch (get_ucall(vcpu, &uc)) {
+ case UCALL_SYNC:
+ vm_enable_cap(vm, KVM_CAP_MSR_PLATFORM_INFO, uc.args[1]);
+ break;
+ case UCALL_DONE:
+ goto done;
+ case UCALL_ABORT:
+ REPORT_GUEST_ASSERT(uc);
+ default:
+ TEST_FAIL("Unexpected ucall %lu", uc.cmd);
+ break;
+ }
+ }
+
+done:
vcpu_set_msr(vcpu, MSR_PLATFORM_INFO, msr_platform_info);
kvm_vm_free(vm);
--
2.44.0.291.gc1ea87d7ee-goog
