Commit | Line | Data |
---|---|---|
9cdeb404 | 1 | /* |
fd19fcd6 BP |
2 | * A simple MCE injection facility for testing different aspects of the RAS |
3 | * code. This driver should be built as module so that it can be loaded | |
4 | * on production kernels for testing purposes. | |
9cdeb404 BP |
5 | * |
6 | * This file may be distributed under the terms of the GNU General Public | |
7 | * License version 2. | |
8 | * | |
fd19fcd6 | 9 | * Copyright (c) 2010-14: Borislav Petkov <bp@alien8.de> |
9cdeb404 BP |
10 | * Advanced Micro Devices Inc. |
11 | */ | |
12 | ||
13 | #include <linux/kobject.h> | |
fd19fcd6 | 14 | #include <linux/debugfs.h> |
51990e82 | 15 | #include <linux/device.h> |
80a2e2e3 | 16 | #include <linux/module.h> |
51756a50 | 17 | #include <linux/cpu.h> |
9cdeb404 BP |
18 | #include <asm/mce.h> |
19 | ||
47ca08a4 | 20 | #include "mce_amd.h" |
9cdeb404 | 21 | |
9cdeb404 BP |
22 | /* |
23 | * Collect all the MCi_XXX settings | |
24 | */ | |
25 | static struct mce i_mce; | |
fd19fcd6 | 26 | static struct dentry *dfs_inj; |
9cdeb404 | 27 | |
fd19fcd6 BP |
28 | #define MCE_INJECT_SET(reg) \ |
29 | static int inj_##reg##_set(void *data, u64 val) \ | |
9cdeb404 | 30 | { \ |
fd19fcd6 | 31 | struct mce *m = (struct mce *)data; \ |
9cdeb404 | 32 | \ |
fd19fcd6 BP |
33 | m->reg = val; \ |
34 | return 0; \ | |
9cdeb404 BP |
35 | } |
36 | ||
fd19fcd6 BP |
37 | MCE_INJECT_SET(status); |
38 | MCE_INJECT_SET(misc); | |
39 | MCE_INJECT_SET(addr); | |
9cdeb404 | 40 | |
fd19fcd6 BP |
41 | #define MCE_INJECT_GET(reg) \ |
42 | static int inj_##reg##_get(void *data, u64 *val) \ | |
9cdeb404 | 43 | { \ |
fd19fcd6 BP |
44 | struct mce *m = (struct mce *)data; \ |
45 | \ | |
46 | *val = m->reg; \ | |
47 | return 0; \ | |
9cdeb404 BP |
48 | } |
49 | ||
fd19fcd6 BP |
50 | MCE_INJECT_GET(status); |
51 | MCE_INJECT_GET(misc); | |
52 | MCE_INJECT_GET(addr); | |
9cdeb404 | 53 | |
fd19fcd6 BP |
54 | DEFINE_SIMPLE_ATTRIBUTE(status_fops, inj_status_get, inj_status_set, "%llx\n"); |
55 | DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n"); | |
56 | DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n"); | |
9cdeb404 | 57 | |
21690934 BP |
58 | /* |
59 | * Caller needs to be make sure this cpu doesn't disappear | |
60 | * from under us, i.e.: get_cpu/put_cpu. | |
61 | */ | |
62 | static int toggle_hw_mce_inject(unsigned int cpu, bool enable) | |
63 | { | |
64 | u32 l, h; | |
65 | int err; | |
66 | ||
67 | err = rdmsr_on_cpu(cpu, MSR_K7_HWCR, &l, &h); | |
68 | if (err) { | |
69 | pr_err("%s: error reading HWCR\n", __func__); | |
70 | return err; | |
71 | } | |
72 | ||
73 | enable ? (l |= BIT(18)) : (l &= ~BIT(18)); | |
74 | ||
75 | err = wrmsr_on_cpu(cpu, MSR_K7_HWCR, l, h); | |
76 | if (err) | |
77 | pr_err("%s: error writing HWCR\n", __func__); | |
78 | ||
79 | return err; | |
80 | } | |
81 | ||
b18f3864 BP |
82 | static int flags_get(void *data, u64 *val) |
83 | { | |
84 | struct mce *m = (struct mce *)data; | |
85 | ||
86 | *val = m->inject_flags; | |
87 | ||
88 | return 0; | |
89 | } | |
90 | ||
91 | static int flags_set(void *data, u64 val) | |
92 | { | |
93 | struct mce *m = (struct mce *)data; | |
94 | ||
95 | m->inject_flags = (u8)val; | |
96 | return 0; | |
97 | } | |
98 | ||
99 | DEFINE_SIMPLE_ATTRIBUTE(flags_fops, flags_get, flags_set, "%llu\n"); | |
100 | ||
101 | /* | |
102 | * On which CPU to inject? | |
103 | */ | |
104 | MCE_INJECT_GET(extcpu); | |
105 | ||
106 | static int inj_extcpu_set(void *data, u64 val) | |
107 | { | |
108 | struct mce *m = (struct mce *)data; | |
109 | ||
110 | if (val >= nr_cpu_ids || !cpu_online(val)) { | |
111 | pr_err("%s: Invalid CPU: %llu\n", __func__, val); | |
112 | return -EINVAL; | |
113 | } | |
114 | m->extcpu = val; | |
115 | return 0; | |
116 | } | |
117 | ||
118 | DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n"); | |
119 | ||
51756a50 BP |
120 | static void trigger_mce(void *info) |
121 | { | |
122 | asm volatile("int $18"); | |
123 | } | |
124 | ||
125 | static void do_inject(void) | |
126 | { | |
127 | u64 mcg_status = 0; | |
128 | unsigned int cpu = i_mce.extcpu; | |
129 | u8 b = i_mce.bank; | |
130 | ||
131 | if (!(i_mce.inject_flags & MCJ_EXCEPTION)) { | |
132 | amd_decode_mce(NULL, 0, &i_mce); | |
133 | return; | |
134 | } | |
135 | ||
136 | get_online_cpus(); | |
137 | if (!cpu_online(cpu)) | |
138 | goto err; | |
139 | ||
140 | /* prep MCE global settings for the injection */ | |
141 | mcg_status = MCG_STATUS_MCIP | MCG_STATUS_EIPV; | |
142 | ||
143 | if (!(i_mce.status & MCI_STATUS_PCC)) | |
144 | mcg_status |= MCG_STATUS_RIPV; | |
145 | ||
146 | toggle_hw_mce_inject(cpu, true); | |
147 | ||
148 | wrmsr_on_cpu(cpu, MSR_IA32_MCG_STATUS, | |
149 | (u32)mcg_status, (u32)(mcg_status >> 32)); | |
150 | ||
151 | wrmsr_on_cpu(cpu, MSR_IA32_MCx_STATUS(b), | |
152 | (u32)i_mce.status, (u32)(i_mce.status >> 32)); | |
153 | ||
154 | wrmsr_on_cpu(cpu, MSR_IA32_MCx_ADDR(b), | |
155 | (u32)i_mce.addr, (u32)(i_mce.addr >> 32)); | |
156 | ||
157 | wrmsr_on_cpu(cpu, MSR_IA32_MCx_MISC(b), | |
158 | (u32)i_mce.misc, (u32)(i_mce.misc >> 32)); | |
159 | ||
160 | toggle_hw_mce_inject(cpu, false); | |
161 | ||
162 | smp_call_function_single(cpu, trigger_mce, NULL, 0); | |
163 | ||
164 | err: | |
165 | put_online_cpus(); | |
166 | ||
167 | } | |
168 | ||
9cdeb404 BP |
169 | /* |
170 | * This denotes into which bank we're injecting and triggers | |
171 | * the injection, at the same time. | |
172 | */ | |
fd19fcd6 | 173 | static int inj_bank_set(void *data, u64 val) |
9cdeb404 | 174 | { |
fd19fcd6 | 175 | struct mce *m = (struct mce *)data; |
9cdeb404 | 176 | |
fd19fcd6 BP |
177 | if (val > 5) { |
178 | if (boot_cpu_data.x86 != 0x15 || val > 6) { | |
179 | pr_err("Non-existent MCE bank: %llu\n", val); | |
1b07ca47 BP |
180 | return -EINVAL; |
181 | } | |
fd19fcd6 | 182 | } |
9cdeb404 | 183 | |
fd19fcd6 | 184 | m->bank = val; |
51756a50 | 185 | do_inject(); |
9cdeb404 | 186 | |
fd19fcd6 | 187 | return 0; |
9cdeb404 BP |
188 | } |
189 | ||
fd19fcd6 | 190 | static int inj_bank_get(void *data, u64 *val) |
9cdeb404 | 191 | { |
fd19fcd6 | 192 | struct mce *m = (struct mce *)data; |
9cdeb404 | 193 | |
fd19fcd6 BP |
194 | *val = m->bank; |
195 | return 0; | |
196 | } | |
9cdeb404 | 197 | |
fd19fcd6 BP |
198 | DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n"); |
199 | ||
200 | struct dfs_node { | |
201 | char *name; | |
202 | struct dentry *d; | |
203 | const struct file_operations *fops; | |
204 | } dfs_fls[] = { | |
205 | { .name = "status", .fops = &status_fops }, | |
206 | { .name = "misc", .fops = &misc_fops }, | |
207 | { .name = "addr", .fops = &addr_fops }, | |
208 | { .name = "bank", .fops = &bank_fops }, | |
b18f3864 BP |
209 | { .name = "flags", .fops = &flags_fops }, |
210 | { .name = "cpu", .fops = &extcpu_fops }, | |
9cdeb404 BP |
211 | }; |
212 | ||
fd19fcd6 | 213 | static int __init init_mce_inject(void) |
9cdeb404 | 214 | { |
fd19fcd6 | 215 | int i; |
9cdeb404 | 216 | |
fd19fcd6 BP |
217 | dfs_inj = debugfs_create_dir("mce-inject", NULL); |
218 | if (!dfs_inj) | |
9cdeb404 BP |
219 | return -EINVAL; |
220 | ||
fd19fcd6 BP |
221 | for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) { |
222 | dfs_fls[i].d = debugfs_create_file(dfs_fls[i].name, | |
223 | S_IRUSR | S_IWUSR, | |
224 | dfs_inj, | |
225 | &i_mce, | |
226 | dfs_fls[i].fops); | |
9cdeb404 | 227 | |
fd19fcd6 BP |
228 | if (!dfs_fls[i].d) |
229 | goto err_dfs_add; | |
9cdeb404 | 230 | } |
fd19fcd6 | 231 | |
9cdeb404 BP |
232 | return 0; |
233 | ||
fd19fcd6 | 234 | err_dfs_add: |
df4b2a30 | 235 | while (--i >= 0) |
fd19fcd6 | 236 | debugfs_remove(dfs_fls[i].d); |
9cdeb404 | 237 | |
fd19fcd6 BP |
238 | debugfs_remove(dfs_inj); |
239 | dfs_inj = NULL; | |
9cdeb404 | 240 | |
fd19fcd6 | 241 | return -ENOMEM; |
9cdeb404 BP |
242 | } |
243 | ||
fd19fcd6 | 244 | static void __exit exit_mce_inject(void) |
9cdeb404 BP |
245 | { |
246 | int i; | |
247 | ||
fd19fcd6 BP |
248 | for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) |
249 | debugfs_remove(dfs_fls[i].d); | |
9cdeb404 | 250 | |
fd19fcd6 | 251 | memset(&dfs_fls, 0, sizeof(dfs_fls)); |
9cdeb404 | 252 | |
fd19fcd6 BP |
253 | debugfs_remove(dfs_inj); |
254 | dfs_inj = NULL; | |
9cdeb404 | 255 | } |
fd19fcd6 BP |
256 | module_init(init_mce_inject); |
257 | module_exit(exit_mce_inject); | |
9cdeb404 BP |
258 | |
259 | MODULE_LICENSE("GPL"); | |
43aff26c | 260 | MODULE_AUTHOR("Borislav Petkov <bp@alien8.de>"); |
9cdeb404 | 261 | MODULE_AUTHOR("AMD Inc."); |
fd19fcd6 | 262 | MODULE_DESCRIPTION("MCE injection facility for RAS testing"); |