selftests: kvm: introduce cpu_has_svm() check

KVM_CAP_NESTED_STATE is now supported for AMD too but smm test acts like it is still Intel only.

Signed-off-by Vitaly Kuznetsov <[email protected]>

---
 tools/testing/selftests/kvm/x86_64/smm_test.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

tools/testing/selftests/kvm/x86_64/smm_test.c +8 -4

index 8230b6bc6b8f..6f8f478b3ceb 100644
@@ -17,6 +17,7 @@
 #include "kvm_util.h"
 
 #include "vmx.h"
+#include "svm_util.h"
 
 #define VCPU_ID	      1
 

@@ -58,7 +59,7 @@ void self_smi(void)
 	      APIC_DEST_SELF | APIC_INT_ASSERT | APIC_DM_SMI);
 }
 
-void guest_code(struct vmx_pages *vmx_pages)
+void guest_code(void *arg)
 {
 	uint64_t apicbase = rdmsr(MSR_IA32_APICBASE);
 

@@ -72,8 +73,11 @@ void guest_code(struct vmx_pages *vmx_pages)
 
 	sync_with_host(4);
 
-	if (vmx_pages) {
-		GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
+	if (arg) {
+		if (cpu_has_svm())
+			generic_svm_setup(arg, NULL, NULL);
+		else
+			GUEST_ASSERT(prepare_for_vmx_operation(arg));
 
 		sync_with_host(5);
 

@@ -87,7 +91,7 @@ void guest_code(struct vmx_pages *vmx_pages)
 
 int main(int argc, char *argv[])
 {
-	vm_vaddr_t vmx_pages_gva = 0;
+	vm_vaddr_t nested_gva = 0;
 
 	struct kvm_regs regs;
 	struct kvm_vm *vm;

@@ -114,8 +118,11 @@ int main(int argc, char *argv[])
 	vcpu_set_msr(vm, VCPU_ID, MSR_IA32_SMBASE, SMRAM_GPA);
 
 	if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {

More tests may want to check if the CPU is Intel or AMD in guest code, separate cpu_has_svm() and put it as static inline to svm_util.h.

Signed-off-by Vitaly Kuznetsov <[email protected]>

---
 tools/testing/selftests/kvm/include/x86_64/svm_util.h | 10 ++++++++++
 tools/testing/selftests/kvm/x86_64/state_test.c       |  9 +--------
 2 files changed, 11 insertions(+), 8 deletions(-)

tools/testing/selftests/kvm/include/x86_64/svm_util.h +0 -0

index cd037917fece..b1057773206a 100644

tools/testing/selftests/kvm/include/x86_64/svm_util.h +4 -0

+
+	return ecx & CPUID_SVM;
+}
+

Quoted 15 lines · Vitaly Kuznetsov

More tests may want to check if the CPU is Intel or AMD in guest code, separate cpu_has_svm() and put it as static inline to svm_util.h.

Signed-off-by Vitaly Kuznetsov <[email protected]>

---
 tools/testing/selftests/kvm/include/x86_64/svm_util.h | 10 ++++++++++
 tools/testing/selftests/kvm/x86_64/state_test.c       |  9 +--------
 2 files changed, 11 insertions(+), 8 deletions(-)

tools/testing/selftests/kvm/include/x86_64/svm_util.h +0 -0

index cd037917fece..b1057773206a 100644

tools/testing/selftests/kvm/include/x86_64/svm_util.h void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_r · line 43

Quoted 9 lines

tools/testing/selftests/kvm/include/x86_64/svm_util.h +6 -0

@@ -35,4 +35,14 @@ void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_r
 void run_guest(struct vmcb *vmcb, uint64_t vmcb_gpa);
 void nested_svm_check_supported(void);
 
+static inline bool cpu_has_svm(void)
+{
+	u32 eax = 0x80000001, ecx;
+
+	asm volatile("cpuid" :
+		     "=a" (eax), "=c" (ecx) : "0" (eax) : "ebx", "edx");

	u32 eax, ecx;

	asm("cpuid" : "=a" (eax), "=c" (ecx) : "a" (0x80000001) : "ebx", "edx");

The volatile shouldn't be needed, e.g. no one should be using this purely for its seralization properties, and I don't see any reason to put the leaf number into a variable.

Alternatively, adding a proper cpuid framework to processor.h would likely be useful in the long run.