Re: [PATCH v4 3/3] selftests: KVM: SVM: Add vmcall test
From: Krish Sadhukhan
Date: Thu Feb 06 2020 - 14:08:43 EST
On 2/6/20 9:39 AM, Wei Huang wrote:
On 02/06 11:47, Eric Auger wrote:
L2 guest calls vmcall and L1 checks the exit status does
correspond.
Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
I verified this patch with my AMD box, both with nested=1 and nested=0. I
also intentionally changed the assertion of exit_code to a different
value (0x082) and the test complained about it. So the test is good.
# selftests: kvm: svm_vmcall_test
# ==== Test Assertion Failure ====
# x86_64/svm_vmcall_test.c:64: false
# pid=2485656 tid=2485656 - Interrupted system call
# 1 0x0000000000401387: main at svm_vmcall_test.c:72
# 2 0x00007fd0978d71a2: ?? ??:0
# 3 0x00000000004013ed: _start at ??:?
# Failed guest assert: vmcb->control.exit_code == SVM_EXIT_VMMCALL
# Testing guest mode: PA-bits:ANY, VA-bits:48, 4K pages
# Guest physical address width detected: 48
not ok 15 selftests: kvm: svm_vmcall_test # exit=254
---
v3 -> v4:
- remove useless includes
- collected Lin's R-b
v2 -> v3:
- remove useless comment and add Vitaly's R-b
---
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/x86_64/svm_vmcall_test.c | 79 +++++++++++++++++++
2 files changed, 80 insertions(+)
create mode 100644 tools/testing/selftests/kvm/x86_64/svm_vmcall_test.c
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 2e770f554cae..b529d3b42c02 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -26,6 +26,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/vmx_dirty_log_test
TEST_GEN_PROGS_x86_64 += x86_64/vmx_set_nested_state_test
TEST_GEN_PROGS_x86_64 += x86_64/vmx_tsc_adjust_test
TEST_GEN_PROGS_x86_64 += x86_64/xss_msr_test
+TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test
TEST_GEN_PROGS_x86_64 += clear_dirty_log_test
TEST_GEN_PROGS_x86_64 += dirty_log_test
TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus
diff --git a/tools/testing/selftests/kvm/x86_64/svm_vmcall_test.c b/tools/testing/selftests/kvm/x86_64/svm_vmcall_test.c
new file mode 100644
index 000000000000..6d3565aab94e
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/svm_vmcall_test.c
Probably rename the file to svm_nested_vmcall_test.c. This matches with
the naming convention of VMX's nested tests. Otherwise people might not know
it is a nested one.
Is it better to give this file a generic name, say, nsvm_tests or
something like that, and place all future nested SVM tests in it, rather
than creating a separate file for each nested test ?
Everything else looks good.
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * svm_vmcall_test
+ *
+ * Copyright (C) 2020, Red Hat, Inc.
+ *
+ * Nested SVM testing: VMCALL
+ */
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "svm_util.h"
+
+#define VCPU_ID 5
+
+static struct kvm_vm *vm;
+
+static inline void l2_vmcall(struct svm_test_data *svm)
+{
+ __asm__ __volatile__("vmcall");
+}
+
+static void l1_guest_code(struct svm_test_data *svm)
+{
+ #define L2_GUEST_STACK_SIZE 64
+ unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
+ struct vmcb *vmcb = svm->vmcb;
+
+ /* Prepare for L2 execution. */
+ generic_svm_setup(svm, l2_vmcall,
+ &l2_guest_stack[L2_GUEST_STACK_SIZE]);
+
+ run_guest(vmcb, svm->vmcb_gpa);
+
+ GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
+ GUEST_DONE();
+}
+
+int main(int argc, char *argv[])
+{
+ vm_vaddr_t svm_gva;
+
+ nested_svm_check_supported();
+
+ vm = vm_create_default(VCPU_ID, 0, (void *) l1_guest_code);
+ vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
+
+ vcpu_alloc_svm(vm, &svm_gva);
+ vcpu_args_set(vm, VCPU_ID, 1, svm_gva);
+
+ for (;;) {
+ volatile struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct ucall uc;
+
+ vcpu_run(vm, VCPU_ID);
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason));
+
+ switch (get_ucall(vm, VCPU_ID, &uc)) {
+ case UCALL_ABORT:
+ TEST_ASSERT(false, "%s",
+ (const char *)uc.args[0]);
+ /* NOT REACHED */
+ case UCALL_SYNC:
+ break;
+ case UCALL_DONE:
+ goto done;
+ default:
+ TEST_ASSERT(false,
+ "Unknown ucall 0x%x.", uc.cmd);
+ }
+ }
+done:
+ kvm_vm_free(vm);
+ return 0;
+}