KVM: selftests: Add a test to get/set triple fault event

Add a selftest for triple fault event:
  - launch the L2 and exit to userspace via I/O.
  - using KVM_SET_VCPU_EVENTS to pend a triple fault event.
  - with the immediate_exit, check the triple fault is pending.
  - run for real with pending triple fault and L1 can see the triple
    fault.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20220524135624.22988-3-chenyi.qiang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 90a6dea..dd5c88c 100644 (file)
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -58,6 +58,7 @@
 /x86_64/xen_vmcall_test
 /x86_64/xss_msr_test
 /x86_64/vmx_pmu_caps_test
+/x86_64/triple_fault_event_test
 /access_tracking_perf_test
 /demand_paging_test
 /dirty_log_test

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index a014368..27e4322 100644 (file)
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -90,6 +90,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/xen_vmcall_test
 TEST_GEN_PROGS_x86_64 += x86_64/sev_migrate_tests
 TEST_GEN_PROGS_x86_64 += x86_64/amx_test
 TEST_GEN_PROGS_x86_64 += x86_64/max_vcpuid_cap_test
+TEST_GEN_PROGS_x86_64 += x86_64/triple_fault_event_test
 TEST_GEN_PROGS_x86_64 += access_tracking_perf_test
 TEST_GEN_PROGS_x86_64 += demand_paging_test
 TEST_GEN_PROGS_x86_64 += dirty_log_test

diff --git a/tools/testing/selftests/kvm/x86_64/triple_fault_event_test.c b/tools/testing/selftests/kvm/x86_64/triple_fault_event_test.c
new file mode 100644 (file)
index 0000000..6e1de06
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/triple_fault_event_test.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "vmx.h"
+
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "kselftest.h"
+
+#define VCPU_ID                        0
+#define ARBITRARY_IO_PORT      0x2000
+
+/* The virtual machine object. */
+static struct kvm_vm *vm;
+
+static void l2_guest_code(void)
+{
+       asm volatile("inb %%dx, %%al"
+                    : : [port] "d" (ARBITRARY_IO_PORT) : "rax");
+}
+
+void l1_guest_code(struct vmx_pages *vmx)
+{
+#define L2_GUEST_STACK_SIZE 64
+       unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
+
+       GUEST_ASSERT(vmx->vmcs_gpa);
+       GUEST_ASSERT(prepare_for_vmx_operation(vmx));
+       GUEST_ASSERT(load_vmcs(vmx));
+
+       prepare_vmcs(vmx, l2_guest_code,
+                    &l2_guest_stack[L2_GUEST_STACK_SIZE]);
+
+       GUEST_ASSERT(!vmlaunch());
+       /* L2 should triple fault after a triple fault event injected. */
+       GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_TRIPLE_FAULT);
+       GUEST_DONE();
+}
+
+int main(void)
+{
+       struct kvm_run *run;
+       struct kvm_vcpu_events events;
+       vm_vaddr_t vmx_pages_gva;
+       struct ucall uc;
+
+       struct kvm_enable_cap cap = {
+               .cap = KVM_CAP_TRIPLE_FAULT_EVENT,
+               .args = {1}
+       };
+
+       if (!nested_vmx_supported()) {
+               print_skip("Nested VMX not supported");
+               exit(KSFT_SKIP);
+       }
+
+       if (!kvm_check_cap(KVM_CAP_TRIPLE_FAULT_EVENT)) {
+               print_skip("KVM_CAP_TRIPLE_FAULT_EVENT not supported");
+               exit(KSFT_SKIP);
+       }
+
+       vm = vm_create_default(VCPU_ID, 0, (void *) l1_guest_code);
+       vm_enable_cap(vm, &cap);
+
+       run = vcpu_state(vm, VCPU_ID);
+       vcpu_alloc_vmx(vm, &vmx_pages_gva);
+       vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);
+       vcpu_run(vm, VCPU_ID);
+
+       TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+                   "Expected KVM_EXIT_IO, got: %u (%s)\n",
+                   run->exit_reason, exit_reason_str(run->exit_reason));
+       TEST_ASSERT(run->io.port == ARBITRARY_IO_PORT,
+                   "Expected IN from port %d from L2, got port %d",
+                   ARBITRARY_IO_PORT, run->io.port);
+       vcpu_events_get(vm, VCPU_ID, &events);
+       events.flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT;
+       events.triple_fault.pending = true;
+       vcpu_events_set(vm, VCPU_ID, &events);
+       run->immediate_exit = true;
+       vcpu_run_complete_io(vm, VCPU_ID);
+
+       vcpu_events_get(vm, VCPU_ID, &events);
+       TEST_ASSERT(events.flags & KVM_VCPUEVENT_VALID_TRIPLE_FAULT,
+                   "Triple fault event invalid");
+       TEST_ASSERT(events.triple_fault.pending,
+                   "No triple fault pending");
+       vcpu_run(vm, VCPU_ID);
+
+       switch (get_ucall(vm, VCPU_ID, &uc)) {
+       case UCALL_DONE:
+               break;
+       case UCALL_ABORT:
+               TEST_FAIL("%s", (const char *)uc.args[0]);
+       default:
+               TEST_FAIL("Unexpected ucall: %lu", uc.cmd);
+       }
+
+}