Merge tag 'media/v4.6-5' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[deliverable/linux.git] / arch / x86 / ras / mce_amd_inj.c
CommitLineData
9cdeb404 1/*
fd19fcd6
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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
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5 *
6 * This file may be distributed under the terms of the GNU General Public
7 * License version 2.
8 *
6c36dfe9 9 * Copyright (c) 2010-15: Borislav Petkov <bp@alien8.de>
9cdeb404
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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>
0451d14d
AG
18#include <linux/string.h>
19#include <linux/uaccess.h>
fa20a2ed 20#include <linux/pci.h>
a1300e50 21
9cdeb404 22#include <asm/mce.h>
ee6825c8 23#include <asm/smp.h>
fa20a2ed 24#include <asm/amd_nb.h>
a1300e50 25#include <asm/irq_vectors.h>
9cdeb404 26
6c36dfe9 27#include "../kernel/cpu/mcheck/mce-internal.h"
9cdeb404 28
9cdeb404
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29/*
30 * Collect all the MCi_XXX settings
31 */
32static struct mce i_mce;
fd19fcd6 33static struct dentry *dfs_inj;
9cdeb404 34
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35static u8 n_banks;
36
0451d14d 37#define MAX_FLAG_OPT_SIZE 3
fa20a2ed 38#define NBCFG 0x44
0451d14d
AG
39
40enum injection_type {
41 SW_INJ = 0, /* SW injection, simply decode the error */
42 HW_INJ, /* Trigger a #MC */
a1300e50
AG
43 DFR_INT_INJ, /* Trigger Deferred error interrupt */
44 THR_INT_INJ, /* Trigger threshold interrupt */
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45 N_INJ_TYPES,
46};
47
48static const char * const flags_options[] = {
49 [SW_INJ] = "sw",
50 [HW_INJ] = "hw",
a1300e50
AG
51 [DFR_INT_INJ] = "df",
52 [THR_INT_INJ] = "th",
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53 NULL
54};
55
56/* Set default injection to SW_INJ */
de277678 57static enum injection_type inj_type = SW_INJ;
0451d14d 58
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59#define MCE_INJECT_SET(reg) \
60static int inj_##reg##_set(void *data, u64 val) \
9cdeb404 61{ \
fd19fcd6 62 struct mce *m = (struct mce *)data; \
9cdeb404 63 \
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64 m->reg = val; \
65 return 0; \
9cdeb404
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66}
67
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68MCE_INJECT_SET(status);
69MCE_INJECT_SET(misc);
70MCE_INJECT_SET(addr);
9cdeb404 71
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72#define MCE_INJECT_GET(reg) \
73static int inj_##reg##_get(void *data, u64 *val) \
9cdeb404 74{ \
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75 struct mce *m = (struct mce *)data; \
76 \
77 *val = m->reg; \
78 return 0; \
9cdeb404
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79}
80
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81MCE_INJECT_GET(status);
82MCE_INJECT_GET(misc);
83MCE_INJECT_GET(addr);
9cdeb404 84
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85DEFINE_SIMPLE_ATTRIBUTE(status_fops, inj_status_get, inj_status_set, "%llx\n");
86DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n");
87DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n");
9cdeb404 88
21690934
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89/*
90 * Caller needs to be make sure this cpu doesn't disappear
91 * from under us, i.e.: get_cpu/put_cpu.
92 */
93static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
94{
95 u32 l, h;
96 int err;
97
98 err = rdmsr_on_cpu(cpu, MSR_K7_HWCR, &l, &h);
99 if (err) {
100 pr_err("%s: error reading HWCR\n", __func__);
101 return err;
102 }
103
104 enable ? (l |= BIT(18)) : (l &= ~BIT(18));
105
106 err = wrmsr_on_cpu(cpu, MSR_K7_HWCR, l, h);
107 if (err)
108 pr_err("%s: error writing HWCR\n", __func__);
109
110 return err;
111}
112
0451d14d 113static int __set_inj(const char *buf)
b18f3864 114{
0451d14d
AG
115 int i;
116
117 for (i = 0; i < N_INJ_TYPES; i++) {
118 if (!strncmp(flags_options[i], buf, strlen(flags_options[i]))) {
119 inj_type = i;
120 return 0;
121 }
122 }
123 return -EINVAL;
124}
125
126static ssize_t flags_read(struct file *filp, char __user *ubuf,
127 size_t cnt, loff_t *ppos)
128{
129 char buf[MAX_FLAG_OPT_SIZE];
130 int n;
b18f3864 131
0451d14d 132 n = sprintf(buf, "%s\n", flags_options[inj_type]);
b18f3864 133
0451d14d 134 return simple_read_from_buffer(ubuf, cnt, ppos, buf, n);
b18f3864
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135}
136
0451d14d
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137static ssize_t flags_write(struct file *filp, const char __user *ubuf,
138 size_t cnt, loff_t *ppos)
b18f3864 139{
0451d14d
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140 char buf[MAX_FLAG_OPT_SIZE], *__buf;
141 int err;
b18f3864 142
0451d14d 143 if (cnt > MAX_FLAG_OPT_SIZE)
85c9306d 144 return -EINVAL;
0451d14d
AG
145
146 if (copy_from_user(&buf, ubuf, cnt))
147 return -EFAULT;
148
149 buf[cnt - 1] = 0;
150
151 /* strip whitespace */
152 __buf = strstrip(buf);
153
154 err = __set_inj(__buf);
155 if (err) {
156 pr_err("%s: Invalid flags value: %s\n", __func__, __buf);
157 return err;
158 }
159
85c9306d 160 *ppos += cnt;
0451d14d 161
85c9306d 162 return cnt;
b18f3864
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163}
164
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165static const struct file_operations flags_fops = {
166 .read = flags_read,
167 .write = flags_write,
168 .llseek = generic_file_llseek,
169};
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170
171/*
172 * On which CPU to inject?
173 */
174MCE_INJECT_GET(extcpu);
175
176static int inj_extcpu_set(void *data, u64 val)
177{
178 struct mce *m = (struct mce *)data;
179
180 if (val >= nr_cpu_ids || !cpu_online(val)) {
181 pr_err("%s: Invalid CPU: %llu\n", __func__, val);
182 return -EINVAL;
183 }
184 m->extcpu = val;
185 return 0;
186}
187
188DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n");
189
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190static void trigger_mce(void *info)
191{
192 asm volatile("int $18");
193}
194
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195static void trigger_dfr_int(void *info)
196{
197 asm volatile("int %0" :: "i" (DEFERRED_ERROR_VECTOR));
198}
199
200static void trigger_thr_int(void *info)
201{
202 asm volatile("int %0" :: "i" (THRESHOLD_APIC_VECTOR));
203}
204
fa20a2ed
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205static u32 get_nbc_for_node(int node_id)
206{
207 struct cpuinfo_x86 *c = &boot_cpu_data;
208 u32 cores_per_node;
209
ee6825c8 210 cores_per_node = (c->x86_max_cores * smp_num_siblings) / amd_get_nodes_per_socket();
fa20a2ed
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211
212 return cores_per_node * node_id;
213}
214
215static void toggle_nb_mca_mst_cpu(u16 nid)
216{
217 struct pci_dev *F3 = node_to_amd_nb(nid)->misc;
218 u32 val;
219 int err;
220
221 if (!F3)
222 return;
223
224 err = pci_read_config_dword(F3, NBCFG, &val);
225 if (err) {
226 pr_err("%s: Error reading F%dx%03x.\n",
227 __func__, PCI_FUNC(F3->devfn), NBCFG);
228 return;
229 }
230
231 if (val & BIT(27))
232 return;
233
234 pr_err("%s: Set D18F3x44[NbMcaToMstCpuEn] which BIOS hasn't done.\n",
235 __func__);
236
237 val |= BIT(27);
238 err = pci_write_config_dword(F3, NBCFG, val);
239 if (err)
240 pr_err("%s: Error writing F%dx%03x.\n",
241 __func__, PCI_FUNC(F3->devfn), NBCFG);
242}
243
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244static void do_inject(void)
245{
246 u64 mcg_status = 0;
247 unsigned int cpu = i_mce.extcpu;
248 u8 b = i_mce.bank;
249
cda9459d
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250 if (i_mce.misc)
251 i_mce.status |= MCI_STATUS_MISCV;
252
0451d14d 253 if (inj_type == SW_INJ) {
6c36dfe9 254 mce_inject_log(&i_mce);
51756a50
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255 return;
256 }
257
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258 /* prep MCE global settings for the injection */
259 mcg_status = MCG_STATUS_MCIP | MCG_STATUS_EIPV;
260
261 if (!(i_mce.status & MCI_STATUS_PCC))
262 mcg_status |= MCG_STATUS_RIPV;
263
a1300e50
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264 /*
265 * Ensure necessary status bits for deferred errors:
266 * - MCx_STATUS[Deferred]: make sure it is a deferred error
267 * - MCx_STATUS[UC] cleared: deferred errors are _not_ UC
268 */
269 if (inj_type == DFR_INT_INJ) {
270 i_mce.status |= MCI_STATUS_DEFERRED;
271 i_mce.status |= (i_mce.status & ~MCI_STATUS_UC);
272 }
273
fa20a2ed
AG
274 /*
275 * For multi node CPUs, logging and reporting of bank 4 errors happens
276 * only on the node base core. Refer to D18F3x44[NbMcaToMstCpuEn] for
277 * Fam10h and later BKDGs.
278 */
279 if (static_cpu_has(X86_FEATURE_AMD_DCM) && b == 4) {
280 toggle_nb_mca_mst_cpu(amd_get_nb_id(cpu));
281 cpu = get_nbc_for_node(amd_get_nb_id(cpu));
282 }
283
6d1e9bf5
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284 get_online_cpus();
285 if (!cpu_online(cpu))
286 goto err;
287
51756a50
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288 toggle_hw_mce_inject(cpu, true);
289
290 wrmsr_on_cpu(cpu, MSR_IA32_MCG_STATUS,
291 (u32)mcg_status, (u32)(mcg_status >> 32));
292
293 wrmsr_on_cpu(cpu, MSR_IA32_MCx_STATUS(b),
294 (u32)i_mce.status, (u32)(i_mce.status >> 32));
295
296 wrmsr_on_cpu(cpu, MSR_IA32_MCx_ADDR(b),
297 (u32)i_mce.addr, (u32)(i_mce.addr >> 32));
298
299 wrmsr_on_cpu(cpu, MSR_IA32_MCx_MISC(b),
300 (u32)i_mce.misc, (u32)(i_mce.misc >> 32));
301
302 toggle_hw_mce_inject(cpu, false);
303
a1300e50
AG
304 switch (inj_type) {
305 case DFR_INT_INJ:
306 smp_call_function_single(cpu, trigger_dfr_int, NULL, 0);
307 break;
308 case THR_INT_INJ:
309 smp_call_function_single(cpu, trigger_thr_int, NULL, 0);
310 break;
311 default:
312 smp_call_function_single(cpu, trigger_mce, NULL, 0);
313 }
51756a50
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314
315err:
316 put_online_cpus();
317
318}
319
9cdeb404
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320/*
321 * This denotes into which bank we're injecting and triggers
322 * the injection, at the same time.
323 */
fd19fcd6 324static int inj_bank_set(void *data, u64 val)
9cdeb404 325{
fd19fcd6 326 struct mce *m = (struct mce *)data;
9cdeb404 327
685d46d7
AG
328 if (val >= n_banks) {
329 pr_err("Non-existent MCE bank: %llu\n", val);
330 return -EINVAL;
fd19fcd6 331 }
9cdeb404 332
fd19fcd6 333 m->bank = val;
51756a50 334 do_inject();
9cdeb404 335
fd19fcd6 336 return 0;
9cdeb404
BP
337}
338
e7f2ea1d 339MCE_INJECT_GET(bank);
9cdeb404 340
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341DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n");
342
99e21fea 343static const char readme_msg[] =
f2f3dca1
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344"Description of the files and their usages:\n"
345"\n"
346"Note1: i refers to the bank number below.\n"
347"Note2: See respective BKDGs for the exact bit definitions of the files below\n"
348"as they mirror the hardware registers.\n"
349"\n"
350"status:\t Set MCi_STATUS: the bits in that MSR control the error type and\n"
351"\t attributes of the error which caused the MCE.\n"
352"\n"
353"misc:\t Set MCi_MISC: provide auxiliary info about the error. It is mostly\n"
354"\t used for error thresholding purposes and its validity is indicated by\n"
355"\t MCi_STATUS[MiscV].\n"
356"\n"
357"addr:\t Error address value to be written to MCi_ADDR. Log address information\n"
358"\t associated with the error.\n"
359"\n"
360"cpu:\t The CPU to inject the error on.\n"
361"\n"
362"bank:\t Specify the bank you want to inject the error into: the number of\n"
363"\t banks in a processor varies and is family/model-specific, therefore, the\n"
364"\t supplied value is sanity-checked. Setting the bank value also triggers the\n"
365"\t injection.\n"
366"\n"
367"flags:\t Injection type to be performed. Writing to this file will trigger a\n"
368"\t real machine check, an APIC interrupt or invoke the error decoder routines\n"
369"\t for AMD processors.\n"
370"\n"
371"\t Allowed error injection types:\n"
372"\t - \"sw\": Software error injection. Decode error to a human-readable \n"
373"\t format only. Safe to use.\n"
374"\t - \"hw\": Hardware error injection. Causes the #MC exception handler to \n"
375"\t handle the error. Be warned: might cause system panic if MCi_STATUS[PCC] \n"
376"\t is set. Therefore, consider setting (debugfs_mountpoint)/mce/fake_panic \n"
377"\t before injecting.\n"
a1300e50
AG
378"\t - \"df\": Trigger APIC interrupt for Deferred error. Causes deferred \n"
379"\t error APIC interrupt handler to handle the error if the feature is \n"
380"\t is present in hardware. \n"
381"\t - \"th\": Trigger APIC interrupt for Threshold errors. Causes threshold \n"
382"\t APIC interrupt handler to handle the error. \n"
f2f3dca1 383"\n";
99e21fea
AG
384
385static ssize_t
386inj_readme_read(struct file *filp, char __user *ubuf,
387 size_t cnt, loff_t *ppos)
388{
389 return simple_read_from_buffer(ubuf, cnt, ppos,
390 readme_msg, strlen(readme_msg));
391}
392
393static const struct file_operations readme_fops = {
394 .read = inj_readme_read,
395};
396
8c2b117f 397static struct dfs_node {
fd19fcd6
BP
398 char *name;
399 struct dentry *d;
400 const struct file_operations *fops;
4c6034e8 401 umode_t perm;
fd19fcd6 402} dfs_fls[] = {
4c6034e8
AG
403 { .name = "status", .fops = &status_fops, .perm = S_IRUSR | S_IWUSR },
404 { .name = "misc", .fops = &misc_fops, .perm = S_IRUSR | S_IWUSR },
405 { .name = "addr", .fops = &addr_fops, .perm = S_IRUSR | S_IWUSR },
406 { .name = "bank", .fops = &bank_fops, .perm = S_IRUSR | S_IWUSR },
407 { .name = "flags", .fops = &flags_fops, .perm = S_IRUSR | S_IWUSR },
408 { .name = "cpu", .fops = &extcpu_fops, .perm = S_IRUSR | S_IWUSR },
99e21fea 409 { .name = "README", .fops = &readme_fops, .perm = S_IRUSR | S_IRGRP | S_IROTH },
9cdeb404
BP
410};
411
fd19fcd6 412static int __init init_mce_inject(void)
9cdeb404 413{
fd19fcd6 414 int i;
685d46d7
AG
415 u64 cap;
416
417 rdmsrl(MSR_IA32_MCG_CAP, cap);
418 n_banks = cap & MCG_BANKCNT_MASK;
9cdeb404 419
fd19fcd6
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420 dfs_inj = debugfs_create_dir("mce-inject", NULL);
421 if (!dfs_inj)
9cdeb404
BP
422 return -EINVAL;
423
fd19fcd6
BP
424 for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) {
425 dfs_fls[i].d = debugfs_create_file(dfs_fls[i].name,
4c6034e8 426 dfs_fls[i].perm,
fd19fcd6
BP
427 dfs_inj,
428 &i_mce,
429 dfs_fls[i].fops);
9cdeb404 430
fd19fcd6
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431 if (!dfs_fls[i].d)
432 goto err_dfs_add;
9cdeb404 433 }
fd19fcd6 434
9cdeb404
BP
435 return 0;
436
fd19fcd6 437err_dfs_add:
df4b2a30 438 while (--i >= 0)
fd19fcd6 439 debugfs_remove(dfs_fls[i].d);
9cdeb404 440
fd19fcd6
BP
441 debugfs_remove(dfs_inj);
442 dfs_inj = NULL;
9cdeb404 443
fd19fcd6 444 return -ENOMEM;
9cdeb404
BP
445}
446
fd19fcd6 447static void __exit exit_mce_inject(void)
9cdeb404
BP
448{
449 int i;
450
fd19fcd6
BP
451 for (i = 0; i < ARRAY_SIZE(dfs_fls); i++)
452 debugfs_remove(dfs_fls[i].d);
9cdeb404 453
fd19fcd6 454 memset(&dfs_fls, 0, sizeof(dfs_fls));
9cdeb404 455
fd19fcd6
BP
456 debugfs_remove(dfs_inj);
457 dfs_inj = NULL;
9cdeb404 458}
fd19fcd6
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459module_init(init_mce_inject);
460module_exit(exit_mce_inject);
9cdeb404
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461
462MODULE_LICENSE("GPL");
43aff26c 463MODULE_AUTHOR("Borislav Petkov <bp@alien8.de>");
9cdeb404 464MODULE_AUTHOR("AMD Inc.");
fd19fcd6 465MODULE_DESCRIPTION("MCE injection facility for RAS testing");
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