KVM: selftests: Extend vmx_nested_tsc_scaling_test to cover SVM

Add SVM L1 code to run the nested guest, and allow the test to run with
SVM as well as VMX.

Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20251021074736.1324328-5-yosry.ahmed@linux.dev
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm
index 89ad8c82a7b20d51259815cefefb84615d3c4449..9ffa0d5c765435cef5ca8ac8cafa5e267dfe765a 100644 (file)
--- a/tools/testing/selftests/kvm/Makefile.kvm
+++ b/tools/testing/selftests/kvm/Makefile.kvm
@@ -91,6 +91,7 @@ TEST_GEN_PROGS_x86 += x86/msrs_test
 TEST_GEN_PROGS_x86 += x86/nested_close_kvm_test
 TEST_GEN_PROGS_x86 += x86/nested_emulation_test
 TEST_GEN_PROGS_x86 += x86/nested_exceptions_test
+TEST_GEN_PROGS_x86 += x86/nested_tsc_scaling_test
 TEST_GEN_PROGS_x86 += x86/platform_info_test
 TEST_GEN_PROGS_x86 += x86/pmu_counters_test
 TEST_GEN_PROGS_x86 += x86/pmu_event_filter_test
@@ -118,7 +119,6 @@ TEST_GEN_PROGS_x86 += x86/vmx_msrs_test
 TEST_GEN_PROGS_x86 += x86/vmx_invalid_nested_guest_state
 TEST_GEN_PROGS_x86 += x86/vmx_set_nested_state_test
 TEST_GEN_PROGS_x86 += x86/vmx_tsc_adjust_test
-TEST_GEN_PROGS_x86 += x86/vmx_nested_tsc_scaling_test
 TEST_GEN_PROGS_x86 += x86/apic_bus_clock_test
 TEST_GEN_PROGS_x86 += x86/xapic_ipi_test
 TEST_GEN_PROGS_x86 += x86/xapic_state_test

diff --git a/tools/testing/selftests/kvm/x86/vmx_nested_tsc_scaling_test.c b/tools/testing/selftests/kvm/x86/nested_tsc_scaling_test.c
similarity index 83%
rename from tools/testing/selftests/kvm/x86/vmx_nested_tsc_scaling_test.c
rename to tools/testing/selftests/kvm/x86/nested_tsc_scaling_test.c
index 1759fa5cb3f29c337a09a5d15569ff028067e2db..4260c9e4f48918f88412f5a00c02eb1e2d7c39e3 100644 (file)
--- a/tools/testing/selftests/kvm/x86/vmx_nested_tsc_scaling_test.c
+++ b/tools/testing/selftests/kvm/x86/nested_tsc_scaling_test.c
@@ -13,6 +13,7 @@
 
 #include "kvm_util.h"
 #include "vmx.h"
+#include "svm_util.h"
 #include "kselftest.h"
 
 /* L2 is scaled up (from L1's perspective) by this factor */
@@ -79,7 +80,30 @@ static void l2_guest_code(void)
        __asm__ __volatile__("vmcall");
 }
 
-static void l1_guest_code(struct vmx_pages *vmx_pages)
+static void l1_svm_code(struct svm_test_data *svm)
+{
+       unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
+
+       /* check that L1's frequency looks alright before launching L2 */
+       check_tsc_freq(UCHECK_L1);
+
+       generic_svm_setup(svm, l2_guest_code,
+                         &l2_guest_stack[L2_GUEST_STACK_SIZE]);
+
+       /* enable TSC scaling for L2 */
+       wrmsr(MSR_AMD64_TSC_RATIO, L2_SCALE_FACTOR << 32);
+
+       /* launch L2 */
+       run_guest(svm->vmcb, svm->vmcb_gpa);
+       GUEST_ASSERT(svm->vmcb->control.exit_code == SVM_EXIT_VMMCALL);
+
+       /* check that L1's frequency still looks good */
+       check_tsc_freq(UCHECK_L1);
+
+       GUEST_DONE();
+}
+
+static void l1_vmx_code(struct vmx_pages *vmx_pages)
 {
        unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
        uint32_t control;
@@ -116,11 +140,19 @@ static void l1_guest_code(struct vmx_pages *vmx_pages)
        GUEST_DONE();
 }
 
+static void l1_guest_code(void *data)
+{
+       if (this_cpu_has(X86_FEATURE_VMX))
+               l1_vmx_code(data);
+       else
+               l1_svm_code(data);
+}
+
 int main(int argc, char *argv[])
 {
        struct kvm_vcpu *vcpu;
        struct kvm_vm *vm;
-       vm_vaddr_t vmx_pages_gva;
+       vm_vaddr_t guest_gva = 0;
 
        uint64_t tsc_start, tsc_end;
        uint64_t tsc_khz;
@@ -129,7 +161,8 @@ int main(int argc, char *argv[])
        uint64_t l1_tsc_freq = 0;
        uint64_t l2_tsc_freq = 0;
 
-       TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
+       TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX) ||
+                    kvm_cpu_has(X86_FEATURE_SVM));
        TEST_REQUIRE(kvm_has_cap(KVM_CAP_TSC_CONTROL));
        TEST_REQUIRE(sys_clocksource_is_based_on_tsc());
 
@@ -152,8 +185,13 @@ int main(int argc, char *argv[])
        printf("real TSC frequency is around: %"PRIu64"\n", l0_tsc_freq);
 
        vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code);
-       vcpu_alloc_vmx(vm, &vmx_pages_gva);
-       vcpu_args_set(vcpu, 1, vmx_pages_gva);
+
+       if (kvm_cpu_has(X86_FEATURE_VMX))
+               vcpu_alloc_vmx(vm, &guest_gva);
+       else
+               vcpu_alloc_svm(vm, &guest_gva);
+
+       vcpu_args_set(vcpu, 1, guest_gva);
 
        tsc_khz = __vcpu_ioctl(vcpu, KVM_GET_TSC_KHZ, NULL);
        TEST_ASSERT(tsc_khz != -1, "vcpu ioctl KVM_GET_TSC_KHZ failed");