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 | |
685d46d7 AG |
28 | static u8 n_banks; |
29 | ||
fd19fcd6 BP |
30 | #define MCE_INJECT_SET(reg) \ |
31 | static int inj_##reg##_set(void *data, u64 val) \ | |
9cdeb404 | 32 | { \ |
fd19fcd6 | 33 | struct mce *m = (struct mce *)data; \ |
9cdeb404 | 34 | \ |
fd19fcd6 BP |
35 | m->reg = val; \ |
36 | return 0; \ | |
9cdeb404 BP |
37 | } |
38 | ||
fd19fcd6 BP |
39 | MCE_INJECT_SET(status); |
40 | MCE_INJECT_SET(misc); | |
41 | MCE_INJECT_SET(addr); | |
9cdeb404 | 42 | |
fd19fcd6 BP |
43 | #define MCE_INJECT_GET(reg) \ |
44 | static int inj_##reg##_get(void *data, u64 *val) \ | |
9cdeb404 | 45 | { \ |
fd19fcd6 BP |
46 | struct mce *m = (struct mce *)data; \ |
47 | \ | |
48 | *val = m->reg; \ | |
49 | return 0; \ | |
9cdeb404 BP |
50 | } |
51 | ||
fd19fcd6 BP |
52 | MCE_INJECT_GET(status); |
53 | MCE_INJECT_GET(misc); | |
54 | MCE_INJECT_GET(addr); | |
9cdeb404 | 55 | |
fd19fcd6 BP |
56 | DEFINE_SIMPLE_ATTRIBUTE(status_fops, inj_status_get, inj_status_set, "%llx\n"); |
57 | DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n"); | |
58 | DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n"); | |
9cdeb404 | 59 | |
21690934 BP |
60 | /* |
61 | * Caller needs to be make sure this cpu doesn't disappear | |
62 | * from under us, i.e.: get_cpu/put_cpu. | |
63 | */ | |
64 | static int toggle_hw_mce_inject(unsigned int cpu, bool enable) | |
65 | { | |
66 | u32 l, h; | |
67 | int err; | |
68 | ||
69 | err = rdmsr_on_cpu(cpu, MSR_K7_HWCR, &l, &h); | |
70 | if (err) { | |
71 | pr_err("%s: error reading HWCR\n", __func__); | |
72 | return err; | |
73 | } | |
74 | ||
75 | enable ? (l |= BIT(18)) : (l &= ~BIT(18)); | |
76 | ||
77 | err = wrmsr_on_cpu(cpu, MSR_K7_HWCR, l, h); | |
78 | if (err) | |
79 | pr_err("%s: error writing HWCR\n", __func__); | |
80 | ||
81 | return err; | |
82 | } | |
83 | ||
b18f3864 BP |
84 | static int flags_get(void *data, u64 *val) |
85 | { | |
86 | struct mce *m = (struct mce *)data; | |
87 | ||
88 | *val = m->inject_flags; | |
89 | ||
90 | return 0; | |
91 | } | |
92 | ||
93 | static int flags_set(void *data, u64 val) | |
94 | { | |
95 | struct mce *m = (struct mce *)data; | |
96 | ||
97 | m->inject_flags = (u8)val; | |
98 | return 0; | |
99 | } | |
100 | ||
101 | DEFINE_SIMPLE_ATTRIBUTE(flags_fops, flags_get, flags_set, "%llu\n"); | |
102 | ||
103 | /* | |
104 | * On which CPU to inject? | |
105 | */ | |
106 | MCE_INJECT_GET(extcpu); | |
107 | ||
108 | static int inj_extcpu_set(void *data, u64 val) | |
109 | { | |
110 | struct mce *m = (struct mce *)data; | |
111 | ||
112 | if (val >= nr_cpu_ids || !cpu_online(val)) { | |
113 | pr_err("%s: Invalid CPU: %llu\n", __func__, val); | |
114 | return -EINVAL; | |
115 | } | |
116 | m->extcpu = val; | |
117 | return 0; | |
118 | } | |
119 | ||
120 | DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n"); | |
121 | ||
51756a50 BP |
122 | static void trigger_mce(void *info) |
123 | { | |
124 | asm volatile("int $18"); | |
125 | } | |
126 | ||
127 | static void do_inject(void) | |
128 | { | |
129 | u64 mcg_status = 0; | |
130 | unsigned int cpu = i_mce.extcpu; | |
131 | u8 b = i_mce.bank; | |
132 | ||
133 | if (!(i_mce.inject_flags & MCJ_EXCEPTION)) { | |
134 | amd_decode_mce(NULL, 0, &i_mce); | |
135 | return; | |
136 | } | |
137 | ||
138 | get_online_cpus(); | |
139 | if (!cpu_online(cpu)) | |
140 | goto err; | |
141 | ||
142 | /* prep MCE global settings for the injection */ | |
143 | mcg_status = MCG_STATUS_MCIP | MCG_STATUS_EIPV; | |
144 | ||
145 | if (!(i_mce.status & MCI_STATUS_PCC)) | |
146 | mcg_status |= MCG_STATUS_RIPV; | |
147 | ||
148 | toggle_hw_mce_inject(cpu, true); | |
149 | ||
150 | wrmsr_on_cpu(cpu, MSR_IA32_MCG_STATUS, | |
151 | (u32)mcg_status, (u32)(mcg_status >> 32)); | |
152 | ||
153 | wrmsr_on_cpu(cpu, MSR_IA32_MCx_STATUS(b), | |
154 | (u32)i_mce.status, (u32)(i_mce.status >> 32)); | |
155 | ||
156 | wrmsr_on_cpu(cpu, MSR_IA32_MCx_ADDR(b), | |
157 | (u32)i_mce.addr, (u32)(i_mce.addr >> 32)); | |
158 | ||
159 | wrmsr_on_cpu(cpu, MSR_IA32_MCx_MISC(b), | |
160 | (u32)i_mce.misc, (u32)(i_mce.misc >> 32)); | |
161 | ||
162 | toggle_hw_mce_inject(cpu, false); | |
163 | ||
164 | smp_call_function_single(cpu, trigger_mce, NULL, 0); | |
165 | ||
166 | err: | |
167 | put_online_cpus(); | |
168 | ||
169 | } | |
170 | ||
9cdeb404 BP |
171 | /* |
172 | * This denotes into which bank we're injecting and triggers | |
173 | * the injection, at the same time. | |
174 | */ | |
fd19fcd6 | 175 | static int inj_bank_set(void *data, u64 val) |
9cdeb404 | 176 | { |
fd19fcd6 | 177 | struct mce *m = (struct mce *)data; |
9cdeb404 | 178 | |
685d46d7 AG |
179 | if (val >= n_banks) { |
180 | pr_err("Non-existent MCE bank: %llu\n", val); | |
181 | return -EINVAL; | |
fd19fcd6 | 182 | } |
9cdeb404 | 183 | |
fd19fcd6 | 184 | m->bank = val; |
51756a50 | 185 | do_inject(); |
9cdeb404 | 186 | |
fd19fcd6 | 187 | return 0; |
9cdeb404 BP |
188 | } |
189 | ||
e7f2ea1d | 190 | MCE_INJECT_GET(bank); |
9cdeb404 | 191 | |
fd19fcd6 BP |
192 | DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n"); |
193 | ||
8c2b117f | 194 | static struct dfs_node { |
fd19fcd6 BP |
195 | char *name; |
196 | struct dentry *d; | |
197 | const struct file_operations *fops; | |
198 | } dfs_fls[] = { | |
199 | { .name = "status", .fops = &status_fops }, | |
200 | { .name = "misc", .fops = &misc_fops }, | |
201 | { .name = "addr", .fops = &addr_fops }, | |
202 | { .name = "bank", .fops = &bank_fops }, | |
b18f3864 BP |
203 | { .name = "flags", .fops = &flags_fops }, |
204 | { .name = "cpu", .fops = &extcpu_fops }, | |
9cdeb404 BP |
205 | }; |
206 | ||
fd19fcd6 | 207 | static int __init init_mce_inject(void) |
9cdeb404 | 208 | { |
fd19fcd6 | 209 | int i; |
685d46d7 AG |
210 | u64 cap; |
211 | ||
212 | rdmsrl(MSR_IA32_MCG_CAP, cap); | |
213 | n_banks = cap & MCG_BANKCNT_MASK; | |
9cdeb404 | 214 | |
fd19fcd6 BP |
215 | dfs_inj = debugfs_create_dir("mce-inject", NULL); |
216 | if (!dfs_inj) | |
9cdeb404 BP |
217 | return -EINVAL; |
218 | ||
fd19fcd6 BP |
219 | for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) { |
220 | dfs_fls[i].d = debugfs_create_file(dfs_fls[i].name, | |
221 | S_IRUSR | S_IWUSR, | |
222 | dfs_inj, | |
223 | &i_mce, | |
224 | dfs_fls[i].fops); | |
9cdeb404 | 225 | |
fd19fcd6 BP |
226 | if (!dfs_fls[i].d) |
227 | goto err_dfs_add; | |
9cdeb404 | 228 | } |
fd19fcd6 | 229 | |
9cdeb404 BP |
230 | return 0; |
231 | ||
fd19fcd6 | 232 | err_dfs_add: |
df4b2a30 | 233 | while (--i >= 0) |
fd19fcd6 | 234 | debugfs_remove(dfs_fls[i].d); |
9cdeb404 | 235 | |
fd19fcd6 BP |
236 | debugfs_remove(dfs_inj); |
237 | dfs_inj = NULL; | |
9cdeb404 | 238 | |
fd19fcd6 | 239 | return -ENOMEM; |
9cdeb404 BP |
240 | } |
241 | ||
fd19fcd6 | 242 | static void __exit exit_mce_inject(void) |
9cdeb404 BP |
243 | { |
244 | int i; | |
245 | ||
fd19fcd6 BP |
246 | for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) |
247 | debugfs_remove(dfs_fls[i].d); | |
9cdeb404 | 248 | |
fd19fcd6 | 249 | memset(&dfs_fls, 0, sizeof(dfs_fls)); |
9cdeb404 | 250 | |
fd19fcd6 BP |
251 | debugfs_remove(dfs_inj); |
252 | dfs_inj = NULL; | |
9cdeb404 | 253 | } |
fd19fcd6 BP |
254 | module_init(init_mce_inject); |
255 | module_exit(exit_mce_inject); | |
9cdeb404 BP |
256 | |
257 | MODULE_LICENSE("GPL"); | |
43aff26c | 258 | MODULE_AUTHOR("Borislav Petkov <bp@alien8.de>"); |
9cdeb404 | 259 | MODULE_AUTHOR("AMD Inc."); |
fd19fcd6 | 260 | MODULE_DESCRIPTION("MCE injection facility for RAS testing"); |