1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Test KVM debugging features. */
3 #include "kvm_util.h"
4 #include "test_util.h"
5
6 #include <linux/kvm.h>
7
8 #define __LC_SVC_NEW_PSW 0x1c0
9 #define __LC_PGM_NEW_PSW 0x1d0
10 #define ICPT_INSTRUCTION 0x04
11 #define IPA0_DIAG 0x8300
12 #define PGM_SPECIFICATION 0x06
13
14 /* Common code for testing single-stepping interruptions. */
15 extern char int_handler[];
16 asm("int_handler:\n"
17 "j .\n");
18
test_step_int_1(struct kvm_vcpu ** vcpu,void * guest_code,size_t new_psw_off,uint64_t * new_psw)19 static struct kvm_vm *test_step_int_1(struct kvm_vcpu **vcpu, void *guest_code,
20 size_t new_psw_off, uint64_t *new_psw)
21 {
22 struct kvm_guest_debug debug = {};
23 struct kvm_regs regs;
24 struct kvm_vm *vm;
25 char *lowcore;
26
27 vm = vm_create_with_one_vcpu(vcpu, guest_code);
28 lowcore = addr_gpa2hva(vm, 0);
29 new_psw[0] = (*vcpu)->run->psw_mask;
30 new_psw[1] = (uint64_t)int_handler;
31 memcpy(lowcore + new_psw_off, new_psw, 16);
32 vcpu_regs_get(*vcpu, ®s);
33 regs.gprs[2] = -1;
34 vcpu_regs_set(*vcpu, ®s);
35 debug.control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
36 vcpu_guest_debug_set(*vcpu, &debug);
37 vcpu_run(*vcpu);
38
39 return vm;
40 }
41
test_step_int(void * guest_code,size_t new_psw_off)42 static void test_step_int(void *guest_code, size_t new_psw_off)
43 {
44 struct kvm_vcpu *vcpu;
45 uint64_t new_psw[2];
46 struct kvm_vm *vm;
47
48 vm = test_step_int_1(&vcpu, guest_code, new_psw_off, new_psw);
49 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_DEBUG);
50 TEST_ASSERT_EQ(vcpu->run->psw_mask, new_psw[0]);
51 TEST_ASSERT_EQ(vcpu->run->psw_addr, new_psw[1]);
52 kvm_vm_free(vm);
53 }
54
55 /* Test single-stepping "boring" program interruptions. */
56 extern char test_step_pgm_guest_code[];
57 asm("test_step_pgm_guest_code:\n"
58 ".insn rr,0x1d00,%r1,%r0 /* dr %r1,%r0 */\n"
59 "j .\n");
60
test_step_pgm(void)61 static void test_step_pgm(void)
62 {
63 test_step_int(test_step_pgm_guest_code, __LC_PGM_NEW_PSW);
64 }
65
66 /*
67 * Test single-stepping program interruptions caused by DIAG.
68 * Userspace emulation must not interfere with single-stepping.
69 */
70 extern char test_step_pgm_diag_guest_code[];
71 asm("test_step_pgm_diag_guest_code:\n"
72 "diag %r0,%r0,0\n"
73 "j .\n");
74
test_step_pgm_diag(void)75 static void test_step_pgm_diag(void)
76 {
77 struct kvm_s390_irq irq = {
78 .type = KVM_S390_PROGRAM_INT,
79 .u.pgm.code = PGM_SPECIFICATION,
80 };
81 struct kvm_vcpu *vcpu;
82 uint64_t new_psw[2];
83 struct kvm_vm *vm;
84
85 vm = test_step_int_1(&vcpu, test_step_pgm_diag_guest_code,
86 __LC_PGM_NEW_PSW, new_psw);
87 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
88 TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_INSTRUCTION);
89 TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa & 0xff00, IPA0_DIAG);
90 vcpu_ioctl(vcpu, KVM_S390_IRQ, &irq);
91 vcpu_run(vcpu);
92 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_DEBUG);
93 TEST_ASSERT_EQ(vcpu->run->psw_mask, new_psw[0]);
94 TEST_ASSERT_EQ(vcpu->run->psw_addr, new_psw[1]);
95 kvm_vm_free(vm);
96 }
97
98 /*
99 * Test single-stepping program interruptions caused by ISKE.
100 * CPUSTAT_KSS handling must not interfere with single-stepping.
101 */
102 extern char test_step_pgm_iske_guest_code[];
103 asm("test_step_pgm_iske_guest_code:\n"
104 "iske %r2,%r2\n"
105 "j .\n");
106
test_step_pgm_iske(void)107 static void test_step_pgm_iske(void)
108 {
109 test_step_int(test_step_pgm_iske_guest_code, __LC_PGM_NEW_PSW);
110 }
111
112 /*
113 * Test single-stepping program interruptions caused by LCTL.
114 * KVM emulation must not interfere with single-stepping.
115 */
116 extern char test_step_pgm_lctl_guest_code[];
117 asm("test_step_pgm_lctl_guest_code:\n"
118 "lctl %c0,%c0,1\n"
119 "j .\n");
120
test_step_pgm_lctl(void)121 static void test_step_pgm_lctl(void)
122 {
123 test_step_int(test_step_pgm_lctl_guest_code, __LC_PGM_NEW_PSW);
124 }
125
126 /* Test single-stepping supervisor-call interruptions. */
127 extern char test_step_svc_guest_code[];
128 asm("test_step_svc_guest_code:\n"
129 "svc 0\n"
130 "j .\n");
131
test_step_svc(void)132 static void test_step_svc(void)
133 {
134 test_step_int(test_step_svc_guest_code, __LC_SVC_NEW_PSW);
135 }
136
137 /* Run all tests above. */
138 static struct testdef {
139 const char *name;
140 void (*test)(void);
141 } testlist[] = {
142 { "single-step pgm", test_step_pgm },
143 { "single-step pgm caused by diag", test_step_pgm_diag },
144 { "single-step pgm caused by iske", test_step_pgm_iske },
145 { "single-step pgm caused by lctl", test_step_pgm_lctl },
146 { "single-step svc", test_step_svc },
147 };
148
main(int argc,char * argv[])149 int main(int argc, char *argv[])
150 {
151 int idx;
152
153 ksft_print_header();
154 ksft_set_plan(ARRAY_SIZE(testlist));
155 for (idx = 0; idx < ARRAY_SIZE(testlist); idx++) {
156 testlist[idx].test();
157 ksft_test_result_pass("%s\n", testlist[idx].name);
158 }
159 ksft_finished();
160 }
161