Extend the 'set_memory_region_test' with a test case which covers the
MMIO during event delivery error handling. The test case
1) Tries to set an IDT descriptor base to point to an MMIO address
2) Generates a #GP
3) Verifies that we got a correct exit reason (KVM_EXIT_INTERNAL_ERROR)
and suberror code (KVM_INTERNAL_ERROR_DELIVERY_EV)
4) Verifies that we got a corrent "faulty" GPA in internal.data[3]
Signed-off-by: Ivan Orlov <iorlov@xxxxxxxxxx>
---
.../selftests/kvm/set_memory_region_test.c | 46 +++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index a8267628e9ed..e9e97346edf1 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -553,6 +553,51 @@ static void test_add_overlapping_private_memory_regions(void)
close(memfd);
kvm_vm_free(vm);
}
+
+static const struct desc_ptr faulty_idt_desc = {
+ .address = MEM_REGION_GPA,
+ .size = 0xFFF,
+};
+
+static void guest_code_faulty_idt_desc(void)
+{
+ __asm__ __volatile__("lidt %0"::"m"(faulty_idt_desc));
+
+ /* Generate a #GP by dereferencing a non-canonical address */
+ *((uint8_t *)0xDEADBEEFDEADBEEFULL) = 0x1;
+
+ /* We should never reach this point */
+ GUEST_ASSERT(0);
+}
+
+/*
+ * This test tries to point the IDT descriptor base to an MMIO address. This action
+ * should cause a KVM internal error, so the VMM could handle such situations gracefully.
+ */
+static void test_faulty_idt_desc(void)
+{
+ struct kvm_vm *vm;
+ struct kvm_vcpu *vcpu;
+
+ pr_info("Testing a faulty IDT descriptor pointing to an MMIO address\n");
+
+ vm = vm_create_with_one_vcpu(&vcpu, guest_code_faulty_idt_desc);
+ virt_map(vm, MEM_REGION_GPA, MEM_REGION_GPA, 1);
+
+ vcpu_run(vcpu);
+ TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_INTERNAL_ERROR);
+ TEST_ASSERT(vcpu->run->internal.suberror == KVM_INTERNAL_ERROR_DELIVERY_EV,
+ "Unexpected suberror = %d", vcpu->run->internal.suberror);
+ TEST_ASSERT(vcpu->run->internal.ndata > 4, "Unexpected internal error data array size = %d",
+ vcpu->run->internal.ndata);
+
+ /* The "faulty" GPA address should be = IDT base + offset of the GP vector */
+ TEST_ASSERT(vcpu->run->internal.data[3] == MEM_REGION_GPA +
+ GP_VECTOR * sizeof(struct idt_entry),
+ "Unexpected GPA = %llx", vcpu->run->internal.data[3]);
+
+ kvm_vm_free(vm);
+}
#endif
int main(int argc, char *argv[])
@@ -568,6 +613,7 @@ int main(int argc, char *argv[])
* KVM_RUN fails with ENOEXEC or EFAULT.
*/
test_zero_memory_regions();
+ test_faulty_idt_desc();
#endif
test_invalid_memory_region_flags();
--
2.43.0
