1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Test for s390x KVM_CAP_SYNC_REGS
4  *
5  * Based on the same test for x86:
6  * Copyright (C) 2018, Google LLC.
7  *
8  * Adaptions for s390x:
9  * Copyright (C) 2019, Red Hat, Inc.
10  *
11  * Test expected behavior of the KVM_CAP_SYNC_REGS functionality.
12  */
13 
14 #define _GNU_SOURCE /* for program_invocation_short_name */
15 #include <fcntl.h>
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <sys/ioctl.h>
20 
21 #include "test_util.h"
22 #include "kvm_util.h"
23 
24 #define VCPU_ID 5
25 
26 static void guest_code(void)
27 {
28 	/*
29 	 * We embed diag 501 here instead of doing a ucall to avoid that
30 	 * the compiler has messed with r11 at the time of the ucall.
31 	 */
32 	asm volatile (
33 		"0:	diag 0,0,0x501\n"
34 		"	ahi 11,1\n"
35 		"	j 0b\n"
36 	);
37 }
38 
39 #define REG_COMPARE(reg) \
40 	TEST_ASSERT(left->reg == right->reg, \
41 		    "Register " #reg \
42 		    " values did not match: 0x%llx, 0x%llx\n", \
43 		    left->reg, right->reg)
44 
45 static void compare_regs(struct kvm_regs *left, struct kvm_sync_regs *right)
46 {
47 	int i;
48 
49 	for (i = 0; i < 16; i++)
50 		REG_COMPARE(gprs[i]);
51 }
52 
53 static void compare_sregs(struct kvm_sregs *left, struct kvm_sync_regs *right)
54 {
55 	int i;
56 
57 	for (i = 0; i < 16; i++)
58 		REG_COMPARE(acrs[i]);
59 
60 	for (i = 0; i < 16; i++)
61 		REG_COMPARE(crs[i]);
62 }
63 
64 #undef REG_COMPARE
65 
66 #define TEST_SYNC_FIELDS   (KVM_SYNC_GPRS|KVM_SYNC_ACRS|KVM_SYNC_CRS)
67 #define INVALID_SYNC_FIELD 0x80000000
68 
69 int main(int argc, char *argv[])
70 {
71 	struct kvm_vm *vm;
72 	struct kvm_run *run;
73 	struct kvm_regs regs;
74 	struct kvm_sregs sregs;
75 	int rv, cap;
76 
77 	/* Tell stdout not to buffer its content */
78 	setbuf(stdout, NULL);
79 
80 	cap = kvm_check_cap(KVM_CAP_SYNC_REGS);
81 	if (!cap) {
82 		fprintf(stderr, "CAP_SYNC_REGS not supported, skipping test\n");
83 		exit(KSFT_SKIP);
84 	}
85 
86 	/* Create VM */
87 	vm = vm_create_default(VCPU_ID, 0, guest_code);
88 
89 	run = vcpu_state(vm, VCPU_ID);
90 
91 	/* Request reading invalid register set from VCPU. */
92 	run->kvm_valid_regs = INVALID_SYNC_FIELD;
93 	rv = _vcpu_run(vm, VCPU_ID);
94 	TEST_ASSERT(rv < 0 && errno == EINVAL,
95 		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
96 		    rv);
97 	vcpu_state(vm, VCPU_ID)->kvm_valid_regs = 0;
98 
99 	run->kvm_valid_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
100 	rv = _vcpu_run(vm, VCPU_ID);
101 	TEST_ASSERT(rv < 0 && errno == EINVAL,
102 		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
103 		    rv);
104 	vcpu_state(vm, VCPU_ID)->kvm_valid_regs = 0;
105 
106 	/* Request setting invalid register set into VCPU. */
107 	run->kvm_dirty_regs = INVALID_SYNC_FIELD;
108 	rv = _vcpu_run(vm, VCPU_ID);
109 	TEST_ASSERT(rv < 0 && errno == EINVAL,
110 		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
111 		    rv);
112 	vcpu_state(vm, VCPU_ID)->kvm_dirty_regs = 0;
113 
114 	run->kvm_dirty_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
115 	rv = _vcpu_run(vm, VCPU_ID);
116 	TEST_ASSERT(rv < 0 && errno == EINVAL,
117 		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
118 		    rv);
119 	vcpu_state(vm, VCPU_ID)->kvm_dirty_regs = 0;
120 
121 	/* Request and verify all valid register sets. */
122 	run->kvm_valid_regs = TEST_SYNC_FIELDS;
123 	rv = _vcpu_run(vm, VCPU_ID);
124 	TEST_ASSERT(rv == 0, "vcpu_run failed: %d\n", rv);
125 	TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,
126 		    "Unexpected exit reason: %u (%s)\n",
127 		    run->exit_reason,
128 		    exit_reason_str(run->exit_reason));
129 	TEST_ASSERT(run->s390_sieic.icptcode == 4 &&
130 		    (run->s390_sieic.ipa >> 8) == 0x83 &&
131 		    (run->s390_sieic.ipb >> 16) == 0x501,
132 		    "Unexpected interception code: ic=%u, ipa=0x%x, ipb=0x%x\n",
133 		    run->s390_sieic.icptcode, run->s390_sieic.ipa,
134 		    run->s390_sieic.ipb);
135 
136 	vcpu_regs_get(vm, VCPU_ID, &regs);
137 	compare_regs(&regs, &run->s.regs);
138 
139 	vcpu_sregs_get(vm, VCPU_ID, &sregs);
140 	compare_sregs(&sregs, &run->s.regs);
141 
142 	/* Set and verify various register values */
143 	run->s.regs.gprs[11] = 0xBAD1DEA;
144 	run->s.regs.acrs[0] = 1 << 11;
145 
146 	run->kvm_valid_regs = TEST_SYNC_FIELDS;
147 	run->kvm_dirty_regs = KVM_SYNC_GPRS | KVM_SYNC_ACRS;
148 	rv = _vcpu_run(vm, VCPU_ID);
149 	TEST_ASSERT(rv == 0, "vcpu_run failed: %d\n", rv);
150 	TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,
151 		    "Unexpected exit reason: %u (%s)\n",
152 		    run->exit_reason,
153 		    exit_reason_str(run->exit_reason));
154 	TEST_ASSERT(run->s.regs.gprs[11] == 0xBAD1DEA + 1,
155 		    "r11 sync regs value incorrect 0x%llx.",
156 		    run->s.regs.gprs[11]);
157 	TEST_ASSERT(run->s.regs.acrs[0]  == 1 << 11,
158 		    "acr0 sync regs value incorrect 0x%llx.",
159 		    run->s.regs.acrs[0]);
160 
161 	vcpu_regs_get(vm, VCPU_ID, &regs);
162 	compare_regs(&regs, &run->s.regs);
163 
164 	vcpu_sregs_get(vm, VCPU_ID, &sregs);
165 	compare_sregs(&sregs, &run->s.regs);
166 
167 	/* Clear kvm_dirty_regs bits, verify new s.regs values are
168 	 * overwritten with existing guest values.
169 	 */
170 	run->kvm_valid_regs = TEST_SYNC_FIELDS;
171 	run->kvm_dirty_regs = 0;
172 	run->s.regs.gprs[11] = 0xDEADBEEF;
173 	rv = _vcpu_run(vm, VCPU_ID);
174 	TEST_ASSERT(rv == 0, "vcpu_run failed: %d\n", rv);
175 	TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,
176 		    "Unexpected exit reason: %u (%s)\n",
177 		    run->exit_reason,
178 		    exit_reason_str(run->exit_reason));
179 	TEST_ASSERT(run->s.regs.gprs[11] != 0xDEADBEEF,
180 		    "r11 sync regs value incorrect 0x%llx.",
181 		    run->s.regs.gprs[11]);
182 
183 	kvm_vm_free(vm);
184 
185 	return 0;
186 }
187