selftests: KVM: s390: check for registers to NOT change on reset

Normal reset and initial CPU reset do not clear all registers. Add a
test that those registers are NOT changed.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/s390x/resets.c

@@ -40,8 +40,22 @@ static void guest_code_initial(void)
 		"	lctlg	8,8,%1\n"
 		"	lctlg	10,10,%2\n"
 		"	lctlg	11,11,%3\n"
-		: : "m" (cr2_59), "m" (cr8_63), "m" (cr10), "m" (cr11) : "2");
-	GUEST_SYNC(0);
+		/* now clobber some general purpose regs */
+		"	llihh	0,0xffff\n"
+		"	llihl	1,0x5555\n"
+		"	llilh	2,0xaaaa\n"
+		"	llill	3,0x0000\n"
+		/* now clobber a floating point reg */
+		"	lghi	4,0x1\n"
+		"	cdgbr	0,4\n"
+		/* now clobber an access reg */
+		"	sar	9,4\n"
+		/* We embed diag 501 here to control register content */
+		"	diag 0,0,0x501\n"
+		:
+		: "m" (cr2_59), "m" (cr8_63), "m" (cr10), "m" (cr11)
+		/* no clobber list as this should not return */
+		);
 }
 
 static void test_one_reg(uint64_t id, uint64_t value)
@@ -98,6 +112,21 @@ static void assert_clear(void)
 		    "vrs0-15 == 0 (sync_regs)");
 }
 
+static void assert_initial_noclear(void)
+{
+	TEST_ASSERT(sync_regs->gprs[0] == 0xffff000000000000UL,
+		    "gpr0 == 0xffff000000000000 (sync_regs)");
+	TEST_ASSERT(sync_regs->gprs[1] == 0x0000555500000000UL,
+		    "gpr1 == 0x0000555500000000 (sync_regs)");
+	TEST_ASSERT(sync_regs->gprs[2] == 0x00000000aaaa0000UL,
+		    "gpr2 == 0x00000000aaaa0000 (sync_regs)");
+	TEST_ASSERT(sync_regs->gprs[3] == 0x0000000000000000UL,
+		    "gpr3 == 0x0000000000000000 (sync_regs)");
+	TEST_ASSERT(sync_regs->fprs[0] == 0x3ff0000000000000UL,
+		    "fpr0 == 0f1 (sync_regs)");
+	TEST_ASSERT(sync_regs->acrs[9] == 1, "ar9 == 1 (sync_regs)");
+}
+
 static void assert_initial(void)
 {
 	struct kvm_sregs sregs;
@@ -140,6 +169,14 @@ static void assert_initial(void)
 	test_one_reg(KVM_REG_S390_CLOCK_COMP, 0);
 }
 
+static void assert_normal_noclear(void)
+{
+	TEST_ASSERT(sync_regs->crs[2] == 0x10, "cr2 == 10 (sync_regs)");
+	TEST_ASSERT(sync_regs->crs[8] == 1, "cr10 == 1 (sync_regs)");
+	TEST_ASSERT(sync_regs->crs[10] == 1, "cr10 == 1 (sync_regs)");
+	TEST_ASSERT(sync_regs->crs[11] == -1, "cr11 == -1 (sync_regs)");
+}
+
 static void assert_normal(void)
 {
 	test_one_reg(KVM_REG_S390_PFTOKEN, KVM_S390_PFAULT_TOKEN_INVALID);
@@ -176,7 +213,13 @@ static void test_normal(void)
 	inject_irq(VCPU_ID);
 
 	vcpu_ioctl(vm, VCPU_ID, KVM_S390_NORMAL_RESET, 0);
+
+	/* must clears */
 	assert_normal();
+	/* must not clears */
+	assert_normal_noclear();
+	assert_initial_noclear();
+
 	kvm_vm_free(vm);
 }
 
@@ -192,8 +235,13 @@ static void test_initial(void)
 	inject_irq(VCPU_ID);
 
 	vcpu_ioctl(vm, VCPU_ID, KVM_S390_INITIAL_RESET, 0);
+
+	/* must clears */
 	assert_normal();
 	assert_initial();
+	/* must not clears */
+	assert_initial_noclear();
+
 	kvm_vm_free(vm);
 }
 
@@ -209,9 +257,12 @@ static void test_clear(void)
 	inject_irq(VCPU_ID);
 
 	vcpu_ioctl(vm, VCPU_ID, KVM_S390_CLEAR_RESET, 0);
+
+	/* must clears */
 	assert_normal();
 	assert_initial();
 	assert_clear();
+
 	kvm_vm_free(vm);
 }