selftests: KVM: s390x: Add reset tests

Test if the registers end up having the correct values after a normal,
initial and clear reset.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20200131100205.74720-6-frankja@linux.ibm.comSigned-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

tools/testing/selftests/kvm/Makefile

@@ -36,6 +36,7 @@ TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus
 
 TEST_GEN_PROGS_s390x = s390x/memop
 TEST_GEN_PROGS_s390x += s390x/sync_regs_test
+TEST_GEN_PROGS_s390x += s390x/resets
 TEST_GEN_PROGS_s390x += dirty_log_test
 TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
 

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

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Test for s390x CPU resets
+ *
+ * Copyright (C) 2020, IBM
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+
+#define VCPU_ID 3
+
+struct kvm_vm *vm;
+struct kvm_run *run;
+struct kvm_sync_regs *regs;
+static uint64_t regs_null[16];
+
+static uint64_t crs[16] = { 0x40000ULL,
+			    0x42000ULL,
+			    0, 0, 0, 0, 0,
+			    0x43000ULL,
+			    0, 0, 0, 0, 0,
+			    0x44000ULL,
+			    0, 0
+};
+
+static void guest_code_initial(void)
+{
+	/* Round toward 0 */
+	uint32_t fpc = 0x11;
+
+	/* Dirty registers */
+	asm volatile (
+		"	lctlg	0,15,%0\n"
+		"	sfpc	%1\n"
+		: : "Q" (crs), "d" (fpc));
+	GUEST_SYNC(0);
+}
+
+static void test_one_reg(uint64_t id, uint64_t value)
+{
+	struct kvm_one_reg reg;
+	uint64_t eval_reg;
+
+	reg.addr = (uintptr_t)&eval_reg;
+	reg.id = id;
+	vcpu_get_reg(vm, VCPU_ID, &reg);
+	TEST_ASSERT(eval_reg == value, "value == %s", value);
+}
+
+static void assert_clear(void)
+{
+	struct kvm_sregs sregs;
+	struct kvm_regs regs;
+	struct kvm_fpu fpu;
+
+	vcpu_regs_get(vm, VCPU_ID, &regs);
+	TEST_ASSERT(!memcmp(&regs.gprs, regs_null, sizeof(regs.gprs)), "grs == 0");
+
+	vcpu_sregs_get(vm, VCPU_ID, &sregs);
+	TEST_ASSERT(!memcmp(&sregs.acrs, regs_null, sizeof(sregs.acrs)), "acrs == 0");
+
+	vcpu_fpu_get(vm, VCPU_ID, &fpu);
+	TEST_ASSERT(!memcmp(&fpu.fprs, regs_null, sizeof(fpu.fprs)), "fprs == 0");
+}
+
+static void assert_initial(void)
+{
+	struct kvm_sregs sregs;
+	struct kvm_fpu fpu;
+
+	vcpu_sregs_get(vm, VCPU_ID, &sregs);
+	TEST_ASSERT(sregs.crs[0] == 0xE0UL, "cr0 == 0xE0");
+	TEST_ASSERT(sregs.crs[14] == 0xC2000000UL, "cr14 == 0xC2000000");
+	TEST_ASSERT(!memcmp(&sregs.crs[1], regs_null, sizeof(sregs.crs[1]) * 12),
+		    "cr1-13 == 0");
+	TEST_ASSERT(sregs.crs[15] == 0, "cr15 == 0");
+
+	vcpu_fpu_get(vm, VCPU_ID, &fpu);
+	TEST_ASSERT(!fpu.fpc, "fpc == 0");
+
+	test_one_reg(KVM_REG_S390_GBEA, 1);
+	test_one_reg(KVM_REG_S390_PP, 0);
+	test_one_reg(KVM_REG_S390_TODPR, 0);
+	test_one_reg(KVM_REG_S390_CPU_TIMER, 0);
+	test_one_reg(KVM_REG_S390_CLOCK_COMP, 0);
+}
+
+static void assert_normal(void)
+{
+	test_one_reg(KVM_REG_S390_PFTOKEN, KVM_S390_PFAULT_TOKEN_INVALID);
+}
+
+static void test_normal(void)
+{
+	printf("Testing normal reset\n");
+	/* Create VM */
+	vm = vm_create_default(VCPU_ID, 0, guest_code_initial);
+	run = vcpu_state(vm, VCPU_ID);
+	regs = &run->s.regs;
+
+	vcpu_run(vm, VCPU_ID);
+
+	vcpu_ioctl(vm, VCPU_ID, KVM_S390_NORMAL_RESET, 0);
+	assert_normal();
+	kvm_vm_free(vm);
+}
+
+static void test_initial(void)
+{
+	printf("Testing initial reset\n");
+	vm = vm_create_default(VCPU_ID, 0, guest_code_initial);
+	run = vcpu_state(vm, VCPU_ID);
+	regs = &run->s.regs;
+
+	vcpu_run(vm, VCPU_ID);
+
+	vcpu_ioctl(vm, VCPU_ID, KVM_S390_INITIAL_RESET, 0);
+	assert_normal();
+	assert_initial();
+	kvm_vm_free(vm);
+}
+
+static void test_clear(void)
+{
+	printf("Testing clear reset\n");
+	vm = vm_create_default(VCPU_ID, 0, guest_code_initial);
+	run = vcpu_state(vm, VCPU_ID);
+	regs = &run->s.regs;
+
+	vcpu_run(vm, VCPU_ID);
+
+	vcpu_ioctl(vm, VCPU_ID, KVM_S390_CLEAR_RESET, 0);
+	assert_normal();
+	assert_initial();
+	assert_clear();
+	kvm_vm_free(vm);
+}
+
+int main(int argc, char *argv[])
+{
+	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
+
+	test_initial();
+	if (kvm_check_cap(KVM_CAP_S390_VCPU_RESETS)) {
+		test_normal();
+		test_clear();
+	}
+	return 0;
+}