1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * CPU subsystem support |
4 | */ |
5 | |
6 | #include <linux/kernel.h> |
7 | #include <linux/module.h> |
8 | #include <linux/init.h> |
9 | #include <linux/sched.h> |
10 | #include <linux/cpu.h> |
11 | #include <linux/topology.h> |
12 | #include <linux/device.h> |
13 | #include <linux/node.h> |
14 | #include <linux/gfp.h> |
15 | #include <linux/slab.h> |
16 | #include <linux/percpu.h> |
17 | #include <linux/acpi.h> |
18 | #include <linux/of.h> |
19 | #include <linux/cpufeature.h> |
20 | #include <linux/tick.h> |
21 | #include <linux/pm_qos.h> |
22 | #include <linux/delay.h> |
23 | #include <linux/sched/isolation.h> |
24 | |
25 | #include "base.h" |
26 | |
27 | static DEFINE_PER_CPU(struct device *, cpu_sys_devices); |
28 | |
29 | static int cpu_subsys_match(struct device *dev, struct device_driver *drv) |
30 | { |
31 | /* ACPI style match is the only one that may succeed. */ |
32 | if (acpi_driver_match_device(dev, drv)) |
33 | return 1; |
34 | |
35 | return 0; |
36 | } |
37 | |
38 | #ifdef CONFIG_HOTPLUG_CPU |
39 | static void change_cpu_under_node(struct cpu *cpu, |
40 | unsigned int from_nid, unsigned int to_nid) |
41 | { |
42 | int cpuid = cpu->dev.id; |
43 | unregister_cpu_under_node(cpu: cpuid, nid: from_nid); |
44 | register_cpu_under_node(cpu: cpuid, nid: to_nid); |
45 | cpu->node_id = to_nid; |
46 | } |
47 | |
48 | static int cpu_subsys_online(struct device *dev) |
49 | { |
50 | struct cpu *cpu = container_of(dev, struct cpu, dev); |
51 | int cpuid = dev->id; |
52 | int from_nid, to_nid; |
53 | int ret; |
54 | int retries = 0; |
55 | |
56 | from_nid = cpu_to_node(cpu: cpuid); |
57 | if (from_nid == NUMA_NO_NODE) |
58 | return -ENODEV; |
59 | |
60 | retry: |
61 | ret = cpu_device_up(dev); |
62 | |
63 | /* |
64 | * If -EBUSY is returned, it is likely that hotplug is temporarily |
65 | * disabled when cpu_hotplug_disable() was called. This condition is |
66 | * transient. So we retry after waiting for an exponentially |
67 | * increasing delay up to a total of at least 620ms as some PCI |
68 | * device initialization can take quite a while. |
69 | */ |
70 | if (ret == -EBUSY) { |
71 | retries++; |
72 | if (retries > 5) |
73 | return ret; |
74 | msleep(msecs: 10 * (1 << retries)); |
75 | goto retry; |
76 | } |
77 | |
78 | /* |
79 | * When hot adding memory to memoryless node and enabling a cpu |
80 | * on the node, node number of the cpu may internally change. |
81 | */ |
82 | to_nid = cpu_to_node(cpu: cpuid); |
83 | if (from_nid != to_nid) |
84 | change_cpu_under_node(cpu, from_nid, to_nid); |
85 | |
86 | return ret; |
87 | } |
88 | |
89 | static int cpu_subsys_offline(struct device *dev) |
90 | { |
91 | return cpu_device_down(dev); |
92 | } |
93 | |
94 | void unregister_cpu(struct cpu *cpu) |
95 | { |
96 | int logical_cpu = cpu->dev.id; |
97 | |
98 | unregister_cpu_under_node(cpu: logical_cpu, cpu_to_node(cpu: logical_cpu)); |
99 | |
100 | device_unregister(dev: &cpu->dev); |
101 | per_cpu(cpu_sys_devices, logical_cpu) = NULL; |
102 | return; |
103 | } |
104 | |
105 | #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE |
106 | static ssize_t cpu_probe_store(struct device *dev, |
107 | struct device_attribute *attr, |
108 | const char *buf, |
109 | size_t count) |
110 | { |
111 | ssize_t cnt; |
112 | int ret; |
113 | |
114 | ret = lock_device_hotplug_sysfs(); |
115 | if (ret) |
116 | return ret; |
117 | |
118 | cnt = arch_cpu_probe(buf, count); |
119 | |
120 | unlock_device_hotplug(); |
121 | return cnt; |
122 | } |
123 | |
124 | static ssize_t cpu_release_store(struct device *dev, |
125 | struct device_attribute *attr, |
126 | const char *buf, |
127 | size_t count) |
128 | { |
129 | ssize_t cnt; |
130 | int ret; |
131 | |
132 | ret = lock_device_hotplug_sysfs(); |
133 | if (ret) |
134 | return ret; |
135 | |
136 | cnt = arch_cpu_release(buf, count); |
137 | |
138 | unlock_device_hotplug(); |
139 | return cnt; |
140 | } |
141 | |
142 | static DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store); |
143 | static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store); |
144 | #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ |
145 | #endif /* CONFIG_HOTPLUG_CPU */ |
146 | |
147 | #ifdef CONFIG_CRASH_DUMP |
148 | #include <linux/kexec.h> |
149 | |
150 | static ssize_t crash_notes_show(struct device *dev, |
151 | struct device_attribute *attr, |
152 | char *buf) |
153 | { |
154 | struct cpu *cpu = container_of(dev, struct cpu, dev); |
155 | unsigned long long addr; |
156 | int cpunum; |
157 | |
158 | cpunum = cpu->dev.id; |
159 | |
160 | /* |
161 | * Might be reading other cpu's data based on which cpu read thread |
162 | * has been scheduled. But cpu data (memory) is allocated once during |
163 | * boot up and this data does not change there after. Hence this |
164 | * operation should be safe. No locking required. |
165 | */ |
166 | addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum)); |
167 | |
168 | return sysfs_emit(buf, fmt: "%llx\n" , addr); |
169 | } |
170 | static DEVICE_ATTR_ADMIN_RO(crash_notes); |
171 | |
172 | static ssize_t crash_notes_size_show(struct device *dev, |
173 | struct device_attribute *attr, |
174 | char *buf) |
175 | { |
176 | return sysfs_emit(buf, fmt: "%zu\n" , sizeof(note_buf_t)); |
177 | } |
178 | static DEVICE_ATTR_ADMIN_RO(crash_notes_size); |
179 | |
180 | static struct attribute *crash_note_cpu_attrs[] = { |
181 | &dev_attr_crash_notes.attr, |
182 | &dev_attr_crash_notes_size.attr, |
183 | NULL |
184 | }; |
185 | |
186 | static const struct attribute_group crash_note_cpu_attr_group = { |
187 | .attrs = crash_note_cpu_attrs, |
188 | }; |
189 | #endif |
190 | |
191 | static const struct attribute_group *common_cpu_attr_groups[] = { |
192 | #ifdef CONFIG_CRASH_DUMP |
193 | &crash_note_cpu_attr_group, |
194 | #endif |
195 | NULL |
196 | }; |
197 | |
198 | static const struct attribute_group *hotplugable_cpu_attr_groups[] = { |
199 | #ifdef CONFIG_CRASH_DUMP |
200 | &crash_note_cpu_attr_group, |
201 | #endif |
202 | NULL |
203 | }; |
204 | |
205 | /* |
206 | * Print cpu online, possible, present, and system maps |
207 | */ |
208 | |
209 | struct cpu_attr { |
210 | struct device_attribute attr; |
211 | const struct cpumask *const map; |
212 | }; |
213 | |
214 | static ssize_t show_cpus_attr(struct device *dev, |
215 | struct device_attribute *attr, |
216 | char *buf) |
217 | { |
218 | struct cpu_attr *ca = container_of(attr, struct cpu_attr, attr); |
219 | |
220 | return cpumap_print_to_pagebuf(list: true, buf, mask: ca->map); |
221 | } |
222 | |
223 | #define _CPU_ATTR(name, map) \ |
224 | { __ATTR(name, 0444, show_cpus_attr, NULL), map } |
225 | |
226 | /* Keep in sync with cpu_subsys_attrs */ |
227 | static struct cpu_attr cpu_attrs[] = { |
228 | _CPU_ATTR(online, &__cpu_online_mask), |
229 | _CPU_ATTR(possible, &__cpu_possible_mask), |
230 | _CPU_ATTR(present, &__cpu_present_mask), |
231 | }; |
232 | |
233 | /* |
234 | * Print values for NR_CPUS and offlined cpus |
235 | */ |
236 | static ssize_t print_cpus_kernel_max(struct device *dev, |
237 | struct device_attribute *attr, char *buf) |
238 | { |
239 | return sysfs_emit(buf, fmt: "%d\n" , NR_CPUS - 1); |
240 | } |
241 | static DEVICE_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL); |
242 | |
243 | /* arch-optional setting to enable display of offline cpus >= nr_cpu_ids */ |
244 | unsigned int total_cpus; |
245 | |
246 | static ssize_t print_cpus_offline(struct device *dev, |
247 | struct device_attribute *attr, char *buf) |
248 | { |
249 | int len = 0; |
250 | cpumask_var_t offline; |
251 | |
252 | /* display offline cpus < nr_cpu_ids */ |
253 | if (!alloc_cpumask_var(mask: &offline, GFP_KERNEL)) |
254 | return -ENOMEM; |
255 | cpumask_andnot(dstp: offline, cpu_possible_mask, cpu_online_mask); |
256 | len += sysfs_emit_at(buf, at: len, fmt: "%*pbl" , cpumask_pr_args(offline)); |
257 | free_cpumask_var(mask: offline); |
258 | |
259 | /* display offline cpus >= nr_cpu_ids */ |
260 | if (total_cpus && nr_cpu_ids < total_cpus) { |
261 | len += sysfs_emit_at(buf, at: len, fmt: "," ); |
262 | |
263 | if (nr_cpu_ids == total_cpus-1) |
264 | len += sysfs_emit_at(buf, at: len, fmt: "%u" , nr_cpu_ids); |
265 | else |
266 | len += sysfs_emit_at(buf, at: len, fmt: "%u-%d" , |
267 | nr_cpu_ids, total_cpus - 1); |
268 | } |
269 | |
270 | len += sysfs_emit_at(buf, at: len, fmt: "\n" ); |
271 | |
272 | return len; |
273 | } |
274 | static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL); |
275 | |
276 | static ssize_t print_cpus_isolated(struct device *dev, |
277 | struct device_attribute *attr, char *buf) |
278 | { |
279 | int len; |
280 | cpumask_var_t isolated; |
281 | |
282 | if (!alloc_cpumask_var(mask: &isolated, GFP_KERNEL)) |
283 | return -ENOMEM; |
284 | |
285 | cpumask_andnot(dstp: isolated, cpu_possible_mask, |
286 | src2p: housekeeping_cpumask(type: HK_TYPE_DOMAIN)); |
287 | len = sysfs_emit(buf, fmt: "%*pbl\n" , cpumask_pr_args(isolated)); |
288 | |
289 | free_cpumask_var(mask: isolated); |
290 | |
291 | return len; |
292 | } |
293 | static DEVICE_ATTR(isolated, 0444, print_cpus_isolated, NULL); |
294 | |
295 | #ifdef CONFIG_NO_HZ_FULL |
296 | static ssize_t print_cpus_nohz_full(struct device *dev, |
297 | struct device_attribute *attr, char *buf) |
298 | { |
299 | return sysfs_emit(buf, "%*pbl\n" , cpumask_pr_args(tick_nohz_full_mask)); |
300 | } |
301 | static DEVICE_ATTR(nohz_full, 0444, print_cpus_nohz_full, NULL); |
302 | #endif |
303 | |
304 | #ifdef CONFIG_CRASH_HOTPLUG |
305 | static ssize_t crash_hotplug_show(struct device *dev, |
306 | struct device_attribute *attr, |
307 | char *buf) |
308 | { |
309 | return sysfs_emit(buf, fmt: "%d\n" , crash_hotplug_cpu_support()); |
310 | } |
311 | static DEVICE_ATTR_ADMIN_RO(crash_hotplug); |
312 | #endif |
313 | |
314 | static void cpu_device_release(struct device *dev) |
315 | { |
316 | /* |
317 | * This is an empty function to prevent the driver core from spitting a |
318 | * warning at us. Yes, I know this is directly opposite of what the |
319 | * documentation for the driver core and kobjects say, and the author |
320 | * of this code has already been publically ridiculed for doing |
321 | * something as foolish as this. However, at this point in time, it is |
322 | * the only way to handle the issue of statically allocated cpu |
323 | * devices. The different architectures will have their cpu device |
324 | * code reworked to properly handle this in the near future, so this |
325 | * function will then be changed to correctly free up the memory held |
326 | * by the cpu device. |
327 | * |
328 | * Never copy this way of doing things, or you too will be made fun of |
329 | * on the linux-kernel list, you have been warned. |
330 | */ |
331 | } |
332 | |
333 | #ifdef CONFIG_GENERIC_CPU_AUTOPROBE |
334 | static ssize_t print_cpu_modalias(struct device *dev, |
335 | struct device_attribute *attr, |
336 | char *buf) |
337 | { |
338 | int len = 0; |
339 | u32 i; |
340 | |
341 | len += sysfs_emit_at(buf, at: len, |
342 | fmt: "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:" , |
343 | CPU_FEATURE_TYPEVAL); |
344 | |
345 | for (i = 0; i < MAX_CPU_FEATURES; i++) |
346 | if (cpu_have_feature(i)) { |
347 | if (len + sizeof(",XXXX\n" ) >= PAGE_SIZE) { |
348 | WARN(1, "CPU features overflow page\n" ); |
349 | break; |
350 | } |
351 | len += sysfs_emit_at(buf, at: len, fmt: ",%04X" , i); |
352 | } |
353 | len += sysfs_emit_at(buf, at: len, fmt: "\n" ); |
354 | return len; |
355 | } |
356 | |
357 | static int cpu_uevent(const struct device *dev, struct kobj_uevent_env *env) |
358 | { |
359 | char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); |
360 | if (buf) { |
361 | print_cpu_modalias(NULL, NULL, buf); |
362 | add_uevent_var(env, format: "MODALIAS=%s" , buf); |
363 | kfree(objp: buf); |
364 | } |
365 | return 0; |
366 | } |
367 | #endif |
368 | |
369 | const struct bus_type cpu_subsys = { |
370 | .name = "cpu" , |
371 | .dev_name = "cpu" , |
372 | .match = cpu_subsys_match, |
373 | #ifdef CONFIG_HOTPLUG_CPU |
374 | .online = cpu_subsys_online, |
375 | .offline = cpu_subsys_offline, |
376 | #endif |
377 | #ifdef CONFIG_GENERIC_CPU_AUTOPROBE |
378 | .uevent = cpu_uevent, |
379 | #endif |
380 | }; |
381 | EXPORT_SYMBOL_GPL(cpu_subsys); |
382 | |
383 | /* |
384 | * register_cpu - Setup a sysfs device for a CPU. |
385 | * @cpu - cpu->hotpluggable field set to 1 will generate a control file in |
386 | * sysfs for this CPU. |
387 | * @num - CPU number to use when creating the device. |
388 | * |
389 | * Initialize and register the CPU device. |
390 | */ |
391 | int register_cpu(struct cpu *cpu, int num) |
392 | { |
393 | int error; |
394 | |
395 | cpu->node_id = cpu_to_node(cpu: num); |
396 | memset(&cpu->dev, 0x00, sizeof(struct device)); |
397 | cpu->dev.id = num; |
398 | cpu->dev.bus = &cpu_subsys; |
399 | cpu->dev.release = cpu_device_release; |
400 | cpu->dev.offline_disabled = !cpu->hotpluggable; |
401 | cpu->dev.offline = !cpu_online(cpu: num); |
402 | cpu->dev.of_node = of_get_cpu_node(cpu: num, NULL); |
403 | cpu->dev.groups = common_cpu_attr_groups; |
404 | if (cpu->hotpluggable) |
405 | cpu->dev.groups = hotplugable_cpu_attr_groups; |
406 | error = device_register(dev: &cpu->dev); |
407 | if (error) { |
408 | put_device(dev: &cpu->dev); |
409 | return error; |
410 | } |
411 | |
412 | per_cpu(cpu_sys_devices, num) = &cpu->dev; |
413 | register_cpu_under_node(cpu: num, cpu_to_node(cpu: num)); |
414 | dev_pm_qos_expose_latency_limit(dev: &cpu->dev, |
415 | PM_QOS_RESUME_LATENCY_NO_CONSTRAINT); |
416 | |
417 | return 0; |
418 | } |
419 | |
420 | struct device *get_cpu_device(unsigned int cpu) |
421 | { |
422 | if (cpu < nr_cpu_ids && cpu_possible(cpu)) |
423 | return per_cpu(cpu_sys_devices, cpu); |
424 | else |
425 | return NULL; |
426 | } |
427 | EXPORT_SYMBOL_GPL(get_cpu_device); |
428 | |
429 | static void device_create_release(struct device *dev) |
430 | { |
431 | kfree(objp: dev); |
432 | } |
433 | |
434 | __printf(4, 0) |
435 | static struct device * |
436 | __cpu_device_create(struct device *parent, void *drvdata, |
437 | const struct attribute_group **groups, |
438 | const char *fmt, va_list args) |
439 | { |
440 | struct device *dev = NULL; |
441 | int retval = -ENOMEM; |
442 | |
443 | dev = kzalloc(size: sizeof(*dev), GFP_KERNEL); |
444 | if (!dev) |
445 | goto error; |
446 | |
447 | device_initialize(dev); |
448 | dev->parent = parent; |
449 | dev->groups = groups; |
450 | dev->release = device_create_release; |
451 | device_set_pm_not_required(dev); |
452 | dev_set_drvdata(dev, data: drvdata); |
453 | |
454 | retval = kobject_set_name_vargs(kobj: &dev->kobj, fmt, vargs: args); |
455 | if (retval) |
456 | goto error; |
457 | |
458 | retval = device_add(dev); |
459 | if (retval) |
460 | goto error; |
461 | |
462 | return dev; |
463 | |
464 | error: |
465 | put_device(dev); |
466 | return ERR_PTR(error: retval); |
467 | } |
468 | |
469 | struct device *cpu_device_create(struct device *parent, void *drvdata, |
470 | const struct attribute_group **groups, |
471 | const char *fmt, ...) |
472 | { |
473 | va_list vargs; |
474 | struct device *dev; |
475 | |
476 | va_start(vargs, fmt); |
477 | dev = __cpu_device_create(parent, drvdata, groups, fmt, args: vargs); |
478 | va_end(vargs); |
479 | return dev; |
480 | } |
481 | EXPORT_SYMBOL_GPL(cpu_device_create); |
482 | |
483 | #ifdef CONFIG_GENERIC_CPU_AUTOPROBE |
484 | static DEVICE_ATTR(modalias, 0444, print_cpu_modalias, NULL); |
485 | #endif |
486 | |
487 | static struct attribute *cpu_root_attrs[] = { |
488 | #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE |
489 | &dev_attr_probe.attr, |
490 | &dev_attr_release.attr, |
491 | #endif |
492 | &cpu_attrs[0].attr.attr, |
493 | &cpu_attrs[1].attr.attr, |
494 | &cpu_attrs[2].attr.attr, |
495 | &dev_attr_kernel_max.attr, |
496 | &dev_attr_offline.attr, |
497 | &dev_attr_isolated.attr, |
498 | #ifdef CONFIG_NO_HZ_FULL |
499 | &dev_attr_nohz_full.attr, |
500 | #endif |
501 | #ifdef CONFIG_CRASH_HOTPLUG |
502 | &dev_attr_crash_hotplug.attr, |
503 | #endif |
504 | #ifdef CONFIG_GENERIC_CPU_AUTOPROBE |
505 | &dev_attr_modalias.attr, |
506 | #endif |
507 | NULL |
508 | }; |
509 | |
510 | static const struct attribute_group cpu_root_attr_group = { |
511 | .attrs = cpu_root_attrs, |
512 | }; |
513 | |
514 | static const struct attribute_group *cpu_root_attr_groups[] = { |
515 | &cpu_root_attr_group, |
516 | NULL, |
517 | }; |
518 | |
519 | bool cpu_is_hotpluggable(unsigned int cpu) |
520 | { |
521 | struct device *dev = get_cpu_device(cpu); |
522 | return dev && container_of(dev, struct cpu, dev)->hotpluggable |
523 | && tick_nohz_cpu_hotpluggable(cpu); |
524 | } |
525 | EXPORT_SYMBOL_GPL(cpu_is_hotpluggable); |
526 | |
527 | #ifdef CONFIG_GENERIC_CPU_DEVICES |
528 | DEFINE_PER_CPU(struct cpu, cpu_devices); |
529 | |
530 | bool __weak arch_cpu_is_hotpluggable(int cpu) |
531 | { |
532 | return false; |
533 | } |
534 | |
535 | int __weak arch_register_cpu(int cpu) |
536 | { |
537 | struct cpu *c = &per_cpu(cpu_devices, cpu); |
538 | |
539 | c->hotpluggable = arch_cpu_is_hotpluggable(cpu); |
540 | |
541 | return register_cpu(cpu: c, num: cpu); |
542 | } |
543 | |
544 | #ifdef CONFIG_HOTPLUG_CPU |
545 | void __weak arch_unregister_cpu(int num) |
546 | { |
547 | unregister_cpu(cpu: &per_cpu(cpu_devices, num)); |
548 | } |
549 | #endif /* CONFIG_HOTPLUG_CPU */ |
550 | #endif /* CONFIG_GENERIC_CPU_DEVICES */ |
551 | |
552 | static void __init cpu_dev_register_generic(void) |
553 | { |
554 | int i, ret; |
555 | |
556 | if (!IS_ENABLED(CONFIG_GENERIC_CPU_DEVICES)) |
557 | return; |
558 | |
559 | for_each_present_cpu(i) { |
560 | ret = arch_register_cpu(cpu: i); |
561 | if (ret) |
562 | pr_warn("register_cpu %d failed (%d)\n" , i, ret); |
563 | } |
564 | } |
565 | |
566 | #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES |
567 | static ssize_t cpu_show_not_affected(struct device *dev, |
568 | struct device_attribute *attr, char *buf) |
569 | { |
570 | return sysfs_emit(buf, fmt: "Not affected\n" ); |
571 | } |
572 | |
573 | #define CPU_SHOW_VULN_FALLBACK(func) \ |
574 | ssize_t cpu_show_##func(struct device *, \ |
575 | struct device_attribute *, char *) \ |
576 | __attribute__((weak, alias("cpu_show_not_affected"))) |
577 | |
578 | CPU_SHOW_VULN_FALLBACK(meltdown); |
579 | CPU_SHOW_VULN_FALLBACK(spectre_v1); |
580 | CPU_SHOW_VULN_FALLBACK(spectre_v2); |
581 | CPU_SHOW_VULN_FALLBACK(spec_store_bypass); |
582 | CPU_SHOW_VULN_FALLBACK(l1tf); |
583 | CPU_SHOW_VULN_FALLBACK(mds); |
584 | CPU_SHOW_VULN_FALLBACK(tsx_async_abort); |
585 | CPU_SHOW_VULN_FALLBACK(itlb_multihit); |
586 | CPU_SHOW_VULN_FALLBACK(srbds); |
587 | CPU_SHOW_VULN_FALLBACK(mmio_stale_data); |
588 | CPU_SHOW_VULN_FALLBACK(retbleed); |
589 | CPU_SHOW_VULN_FALLBACK(spec_rstack_overflow); |
590 | CPU_SHOW_VULN_FALLBACK(gds); |
591 | CPU_SHOW_VULN_FALLBACK(reg_file_data_sampling); |
592 | |
593 | static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL); |
594 | static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL); |
595 | static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL); |
596 | static DEVICE_ATTR(spec_store_bypass, 0444, cpu_show_spec_store_bypass, NULL); |
597 | static DEVICE_ATTR(l1tf, 0444, cpu_show_l1tf, NULL); |
598 | static DEVICE_ATTR(mds, 0444, cpu_show_mds, NULL); |
599 | static DEVICE_ATTR(tsx_async_abort, 0444, cpu_show_tsx_async_abort, NULL); |
600 | static DEVICE_ATTR(itlb_multihit, 0444, cpu_show_itlb_multihit, NULL); |
601 | static DEVICE_ATTR(srbds, 0444, cpu_show_srbds, NULL); |
602 | static DEVICE_ATTR(mmio_stale_data, 0444, cpu_show_mmio_stale_data, NULL); |
603 | static DEVICE_ATTR(retbleed, 0444, cpu_show_retbleed, NULL); |
604 | static DEVICE_ATTR(spec_rstack_overflow, 0444, cpu_show_spec_rstack_overflow, NULL); |
605 | static DEVICE_ATTR(gather_data_sampling, 0444, cpu_show_gds, NULL); |
606 | static DEVICE_ATTR(reg_file_data_sampling, 0444, cpu_show_reg_file_data_sampling, NULL); |
607 | |
608 | static struct attribute *cpu_root_vulnerabilities_attrs[] = { |
609 | &dev_attr_meltdown.attr, |
610 | &dev_attr_spectre_v1.attr, |
611 | &dev_attr_spectre_v2.attr, |
612 | &dev_attr_spec_store_bypass.attr, |
613 | &dev_attr_l1tf.attr, |
614 | &dev_attr_mds.attr, |
615 | &dev_attr_tsx_async_abort.attr, |
616 | &dev_attr_itlb_multihit.attr, |
617 | &dev_attr_srbds.attr, |
618 | &dev_attr_mmio_stale_data.attr, |
619 | &dev_attr_retbleed.attr, |
620 | &dev_attr_spec_rstack_overflow.attr, |
621 | &dev_attr_gather_data_sampling.attr, |
622 | &dev_attr_reg_file_data_sampling.attr, |
623 | NULL |
624 | }; |
625 | |
626 | static const struct attribute_group cpu_root_vulnerabilities_group = { |
627 | .name = "vulnerabilities" , |
628 | .attrs = cpu_root_vulnerabilities_attrs, |
629 | }; |
630 | |
631 | static void __init cpu_register_vulnerabilities(void) |
632 | { |
633 | struct device *dev = bus_get_dev_root(bus: &cpu_subsys); |
634 | |
635 | if (dev) { |
636 | if (sysfs_create_group(kobj: &dev->kobj, grp: &cpu_root_vulnerabilities_group)) |
637 | pr_err("Unable to register CPU vulnerabilities\n" ); |
638 | put_device(dev); |
639 | } |
640 | } |
641 | |
642 | #else |
643 | static inline void cpu_register_vulnerabilities(void) { } |
644 | #endif |
645 | |
646 | void __init cpu_dev_init(void) |
647 | { |
648 | if (subsys_system_register(subsys: &cpu_subsys, groups: cpu_root_attr_groups)) |
649 | panic(fmt: "Failed to register CPU subsystem" ); |
650 | |
651 | cpu_dev_register_generic(); |
652 | cpu_register_vulnerabilities(); |
653 | } |
654 | |