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Merge tag 'trace-v6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...
[linux-2.6-block.git] / kernel / trace / trace_kprobe.c
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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Kprobes-based tracing events
4 *
5 * Created by Masami Hiramatsu <mhiramat@redhat.com>
6 *
7 */
8#define pr_fmt(fmt) "trace_kprobe: " fmt
9
10#include <linux/bpf-cgroup.h>
11#include <linux/security.h>
12#include <linux/module.h>
13#include <linux/uaccess.h>
14#include <linux/rculist.h>
15#include <linux/error-injection.h>
16
17#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
18
19#include "trace_dynevent.h"
20#include "trace_kprobe_selftest.h"
21#include "trace_probe.h"
22#include "trace_probe_tmpl.h"
23#include "trace_probe_kernel.h"
24
25#define KPROBE_EVENT_SYSTEM "kprobes"
26#define KRETPROBE_MAXACTIVE_MAX 4096
27
28/* Kprobe early definition from command line */
29static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata;
30
31static int __init set_kprobe_boot_events(char *str)
32{
33 strscpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE);
34 disable_tracing_selftest("running kprobe events");
35
36 return 1;
37}
38__setup("kprobe_event=", set_kprobe_boot_events);
39
40static int trace_kprobe_create(const char *raw_command);
41static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev);
42static int trace_kprobe_release(struct dyn_event *ev);
43static bool trace_kprobe_is_busy(struct dyn_event *ev);
44static bool trace_kprobe_match(const char *system, const char *event,
45 int argc, const char **argv, struct dyn_event *ev);
46
47static struct dyn_event_operations trace_kprobe_ops = {
48 .create = trace_kprobe_create,
49 .show = trace_kprobe_show,
50 .is_busy = trace_kprobe_is_busy,
51 .free = trace_kprobe_release,
52 .match = trace_kprobe_match,
53};
54
55/*
56 * Kprobe event core functions
57 */
58struct trace_kprobe {
59 struct dyn_event devent;
60 struct kretprobe rp; /* Use rp.kp for kprobe use */
61 unsigned long __percpu *nhit;
62 const char *symbol; /* symbol name */
63 struct trace_probe tp;
64};
65
66static bool is_trace_kprobe(struct dyn_event *ev)
67{
68 return ev->ops == &trace_kprobe_ops;
69}
70
71static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev)
72{
73 return container_of(ev, struct trace_kprobe, devent);
74}
75
76/**
77 * for_each_trace_kprobe - iterate over the trace_kprobe list
78 * @pos: the struct trace_kprobe * for each entry
79 * @dpos: the struct dyn_event * to use as a loop cursor
80 */
81#define for_each_trace_kprobe(pos, dpos) \
82 for_each_dyn_event(dpos) \
83 if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos)))
84
85static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
86{
87 return tk->rp.handler != NULL;
88}
89
90static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk)
91{
92 return tk->symbol ? tk->symbol : "unknown";
93}
94
95static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk)
96{
97 return tk->rp.kp.offset;
98}
99
100static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk)
101{
102 return kprobe_gone(&tk->rp.kp);
103}
104
105static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk,
106 struct module *mod)
107{
108 int len = strlen(module_name(mod));
109 const char *name = trace_kprobe_symbol(tk);
110
111 return strncmp(module_name(mod), name, len) == 0 && name[len] == ':';
112}
113
114#ifdef CONFIG_MODULES
115static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
116{
117 char *p;
118 bool ret;
119
120 if (!tk->symbol)
121 return false;
122 p = strchr(tk->symbol, ':');
123 if (!p)
124 return true;
125 *p = '\0';
126 rcu_read_lock_sched();
127 ret = !!find_module(tk->symbol);
128 rcu_read_unlock_sched();
129 *p = ':';
130
131 return ret;
132}
133#else
134static inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
135{
136 return false;
137}
138#endif
139
140static bool trace_kprobe_is_busy(struct dyn_event *ev)
141{
142 struct trace_kprobe *tk = to_trace_kprobe(ev);
143
144 return trace_probe_is_enabled(&tk->tp);
145}
146
147static bool trace_kprobe_match_command_head(struct trace_kprobe *tk,
148 int argc, const char **argv)
149{
150 char buf[MAX_ARGSTR_LEN + 1];
151
152 if (!argc)
153 return true;
154
155 if (!tk->symbol)
156 snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr);
157 else if (tk->rp.kp.offset)
158 snprintf(buf, sizeof(buf), "%s+%u",
159 trace_kprobe_symbol(tk), tk->rp.kp.offset);
160 else
161 snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk));
162 if (strcmp(buf, argv[0]))
163 return false;
164 argc--; argv++;
165
166 return trace_probe_match_command_args(&tk->tp, argc, argv);
167}
168
169static bool trace_kprobe_match(const char *system, const char *event,
170 int argc, const char **argv, struct dyn_event *ev)
171{
172 struct trace_kprobe *tk = to_trace_kprobe(ev);
173
174 return (event[0] == '\0' ||
175 strcmp(trace_probe_name(&tk->tp), event) == 0) &&
176 (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) &&
177 trace_kprobe_match_command_head(tk, argc, argv);
178}
179
180static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
181{
182 unsigned long nhit = 0;
183 int cpu;
184
185 for_each_possible_cpu(cpu)
186 nhit += *per_cpu_ptr(tk->nhit, cpu);
187
188 return nhit;
189}
190
191static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk)
192{
193 return !(list_empty(&tk->rp.kp.list) &&
194 hlist_unhashed(&tk->rp.kp.hlist));
195}
196
197/* Return 0 if it fails to find the symbol address */
198static nokprobe_inline
199unsigned long trace_kprobe_address(struct trace_kprobe *tk)
200{
201 unsigned long addr;
202
203 if (tk->symbol) {
204 addr = (unsigned long)
205 kallsyms_lookup_name(trace_kprobe_symbol(tk));
206 if (addr)
207 addr += tk->rp.kp.offset;
208 } else {
209 addr = (unsigned long)tk->rp.kp.addr;
210 }
211 return addr;
212}
213
214static nokprobe_inline struct trace_kprobe *
215trace_kprobe_primary_from_call(struct trace_event_call *call)
216{
217 struct trace_probe *tp;
218
219 tp = trace_probe_primary_from_call(call);
220 if (WARN_ON_ONCE(!tp))
221 return NULL;
222
223 return container_of(tp, struct trace_kprobe, tp);
224}
225
226bool trace_kprobe_on_func_entry(struct trace_event_call *call)
227{
228 struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
229
230 return tk ? (kprobe_on_func_entry(tk->rp.kp.addr,
231 tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name,
232 tk->rp.kp.addr ? 0 : tk->rp.kp.offset) == 0) : false;
233}
234
235bool trace_kprobe_error_injectable(struct trace_event_call *call)
236{
237 struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
238
239 return tk ? within_error_injection_list(trace_kprobe_address(tk)) :
240 false;
241}
242
243static int register_kprobe_event(struct trace_kprobe *tk);
244static int unregister_kprobe_event(struct trace_kprobe *tk);
245
246static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
247static int kretprobe_dispatcher(struct kretprobe_instance *ri,
248 struct pt_regs *regs);
249
250static void free_trace_kprobe(struct trace_kprobe *tk)
251{
252 if (tk) {
253 trace_probe_cleanup(&tk->tp);
254 kfree(tk->symbol);
255 free_percpu(tk->nhit);
256 kfree(tk);
257 }
258}
259
260/*
261 * Allocate new trace_probe and initialize it (including kprobes).
262 */
263static struct trace_kprobe *alloc_trace_kprobe(const char *group,
264 const char *event,
265 void *addr,
266 const char *symbol,
267 unsigned long offs,
268 int maxactive,
269 int nargs, bool is_return)
270{
271 struct trace_kprobe *tk;
272 int ret = -ENOMEM;
273
274 tk = kzalloc(struct_size(tk, tp.args, nargs), GFP_KERNEL);
275 if (!tk)
276 return ERR_PTR(ret);
277
278 tk->nhit = alloc_percpu(unsigned long);
279 if (!tk->nhit)
280 goto error;
281
282 if (symbol) {
283 tk->symbol = kstrdup(symbol, GFP_KERNEL);
284 if (!tk->symbol)
285 goto error;
286 tk->rp.kp.symbol_name = tk->symbol;
287 tk->rp.kp.offset = offs;
288 } else
289 tk->rp.kp.addr = addr;
290
291 if (is_return)
292 tk->rp.handler = kretprobe_dispatcher;
293 else
294 tk->rp.kp.pre_handler = kprobe_dispatcher;
295
296 tk->rp.maxactive = maxactive;
297 INIT_HLIST_NODE(&tk->rp.kp.hlist);
298 INIT_LIST_HEAD(&tk->rp.kp.list);
299
300 ret = trace_probe_init(&tk->tp, event, group, false, nargs);
301 if (ret < 0)
302 goto error;
303
304 dyn_event_init(&tk->devent, &trace_kprobe_ops);
305 return tk;
306error:
307 free_trace_kprobe(tk);
308 return ERR_PTR(ret);
309}
310
311static struct trace_kprobe *find_trace_kprobe(const char *event,
312 const char *group)
313{
314 struct dyn_event *pos;
315 struct trace_kprobe *tk;
316
317 for_each_trace_kprobe(tk, pos)
318 if (strcmp(trace_probe_name(&tk->tp), event) == 0 &&
319 strcmp(trace_probe_group_name(&tk->tp), group) == 0)
320 return tk;
321 return NULL;
322}
323
324static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
325{
326 int ret = 0;
327
328 if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) {
329 if (trace_kprobe_is_return(tk))
330 ret = enable_kretprobe(&tk->rp);
331 else
332 ret = enable_kprobe(&tk->rp.kp);
333 }
334
335 return ret;
336}
337
338static void __disable_trace_kprobe(struct trace_probe *tp)
339{
340 struct trace_kprobe *tk;
341
342 list_for_each_entry(tk, trace_probe_probe_list(tp), tp.list) {
343 if (!trace_kprobe_is_registered(tk))
344 continue;
345 if (trace_kprobe_is_return(tk))
346 disable_kretprobe(&tk->rp);
347 else
348 disable_kprobe(&tk->rp.kp);
349 }
350}
351
352/*
353 * Enable trace_probe
354 * if the file is NULL, enable "perf" handler, or enable "trace" handler.
355 */
356static int enable_trace_kprobe(struct trace_event_call *call,
357 struct trace_event_file *file)
358{
359 struct trace_probe *tp;
360 struct trace_kprobe *tk;
361 bool enabled;
362 int ret = 0;
363
364 tp = trace_probe_primary_from_call(call);
365 if (WARN_ON_ONCE(!tp))
366 return -ENODEV;
367 enabled = trace_probe_is_enabled(tp);
368
369 /* This also changes "enabled" state */
370 if (file) {
371 ret = trace_probe_add_file(tp, file);
372 if (ret)
373 return ret;
374 } else
375 trace_probe_set_flag(tp, TP_FLAG_PROFILE);
376
377 if (enabled)
378 return 0;
379
380 list_for_each_entry(tk, trace_probe_probe_list(tp), tp.list) {
381 if (trace_kprobe_has_gone(tk))
382 continue;
383 ret = __enable_trace_kprobe(tk);
384 if (ret)
385 break;
386 enabled = true;
387 }
388
389 if (ret) {
390 /* Failed to enable one of them. Roll back all */
391 if (enabled)
392 __disable_trace_kprobe(tp);
393 if (file)
394 trace_probe_remove_file(tp, file);
395 else
396 trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
397 }
398
399 return ret;
400}
401
402/*
403 * Disable trace_probe
404 * if the file is NULL, disable "perf" handler, or disable "trace" handler.
405 */
406static int disable_trace_kprobe(struct trace_event_call *call,
407 struct trace_event_file *file)
408{
409 struct trace_probe *tp;
410
411 tp = trace_probe_primary_from_call(call);
412 if (WARN_ON_ONCE(!tp))
413 return -ENODEV;
414
415 if (file) {
416 if (!trace_probe_get_file_link(tp, file))
417 return -ENOENT;
418 if (!trace_probe_has_single_file(tp))
419 goto out;
420 trace_probe_clear_flag(tp, TP_FLAG_TRACE);
421 } else
422 trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
423
424 if (!trace_probe_is_enabled(tp))
425 __disable_trace_kprobe(tp);
426
427 out:
428 if (file)
429 /*
430 * Synchronization is done in below function. For perf event,
431 * file == NULL and perf_trace_event_unreg() calls
432 * tracepoint_synchronize_unregister() to ensure synchronize
433 * event. We don't need to care about it.
434 */
435 trace_probe_remove_file(tp, file);
436
437 return 0;
438}
439
440#if defined(CONFIG_DYNAMIC_FTRACE) && \
441 !defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE)
442static bool __within_notrace_func(unsigned long addr)
443{
444 unsigned long offset, size;
445
446 if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset))
447 return false;
448
449 /* Get the entry address of the target function */
450 addr -= offset;
451
452 /*
453 * Since ftrace_location_range() does inclusive range check, we need
454 * to subtract 1 byte from the end address.
455 */
456 return !ftrace_location_range(addr, addr + size - 1);
457}
458
459static bool within_notrace_func(struct trace_kprobe *tk)
460{
461 unsigned long addr = trace_kprobe_address(tk);
462 char symname[KSYM_NAME_LEN], *p;
463
464 if (!__within_notrace_func(addr))
465 return false;
466
467 /* Check if the address is on a suffixed-symbol */
468 if (!lookup_symbol_name(addr, symname)) {
469 p = strchr(symname, '.');
470 if (!p)
471 return true;
472 *p = '\0';
473 addr = (unsigned long)kprobe_lookup_name(symname, 0);
474 if (addr)
475 return __within_notrace_func(addr);
476 }
477
478 return true;
479}
480#else
481#define within_notrace_func(tk) (false)
482#endif
483
484/* Internal register function - just handle k*probes and flags */
485static int __register_trace_kprobe(struct trace_kprobe *tk)
486{
487 int i, ret;
488
489 ret = security_locked_down(LOCKDOWN_KPROBES);
490 if (ret)
491 return ret;
492
493 if (trace_kprobe_is_registered(tk))
494 return -EINVAL;
495
496 if (within_notrace_func(tk)) {
497 pr_warn("Could not probe notrace function %ps\n",
498 (void *)trace_kprobe_address(tk));
499 return -EINVAL;
500 }
501
502 for (i = 0; i < tk->tp.nr_args; i++) {
503 ret = traceprobe_update_arg(&tk->tp.args[i]);
504 if (ret)
505 return ret;
506 }
507
508 /* Set/clear disabled flag according to tp->flag */
509 if (trace_probe_is_enabled(&tk->tp))
510 tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
511 else
512 tk->rp.kp.flags |= KPROBE_FLAG_DISABLED;
513
514 if (trace_kprobe_is_return(tk))
515 ret = register_kretprobe(&tk->rp);
516 else
517 ret = register_kprobe(&tk->rp.kp);
518
519 return ret;
520}
521
522/* Internal unregister function - just handle k*probes and flags */
523static void __unregister_trace_kprobe(struct trace_kprobe *tk)
524{
525 if (trace_kprobe_is_registered(tk)) {
526 if (trace_kprobe_is_return(tk))
527 unregister_kretprobe(&tk->rp);
528 else
529 unregister_kprobe(&tk->rp.kp);
530 /* Cleanup kprobe for reuse and mark it unregistered */
531 INIT_HLIST_NODE(&tk->rp.kp.hlist);
532 INIT_LIST_HEAD(&tk->rp.kp.list);
533 if (tk->rp.kp.symbol_name)
534 tk->rp.kp.addr = NULL;
535 }
536}
537
538/* Unregister a trace_probe and probe_event */
539static int unregister_trace_kprobe(struct trace_kprobe *tk)
540{
541 /* If other probes are on the event, just unregister kprobe */
542 if (trace_probe_has_sibling(&tk->tp))
543 goto unreg;
544
545 /* Enabled event can not be unregistered */
546 if (trace_probe_is_enabled(&tk->tp))
547 return -EBUSY;
548
549 /* If there's a reference to the dynamic event */
550 if (trace_event_dyn_busy(trace_probe_event_call(&tk->tp)))
551 return -EBUSY;
552
553 /* Will fail if probe is being used by ftrace or perf */
554 if (unregister_kprobe_event(tk))
555 return -EBUSY;
556
557unreg:
558 __unregister_trace_kprobe(tk);
559 dyn_event_remove(&tk->devent);
560 trace_probe_unlink(&tk->tp);
561
562 return 0;
563}
564
565static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
566 struct trace_kprobe *comp)
567{
568 struct trace_probe_event *tpe = orig->tp.event;
569 int i;
570
571 list_for_each_entry(orig, &tpe->probes, tp.list) {
572 if (strcmp(trace_kprobe_symbol(orig),
573 trace_kprobe_symbol(comp)) ||
574 trace_kprobe_offset(orig) != trace_kprobe_offset(comp))
575 continue;
576
577 /*
578 * trace_probe_compare_arg_type() ensured that nr_args and
579 * each argument name and type are same. Let's compare comm.
580 */
581 for (i = 0; i < orig->tp.nr_args; i++) {
582 if (strcmp(orig->tp.args[i].comm,
583 comp->tp.args[i].comm))
584 break;
585 }
586
587 if (i == orig->tp.nr_args)
588 return true;
589 }
590
591 return false;
592}
593
594static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to)
595{
596 int ret;
597
598 ret = trace_probe_compare_arg_type(&tk->tp, &to->tp);
599 if (ret) {
600 /* Note that argument starts index = 2 */
601 trace_probe_log_set_index(ret + 1);
602 trace_probe_log_err(0, DIFF_ARG_TYPE);
603 return -EEXIST;
604 }
605 if (trace_kprobe_has_same_kprobe(to, tk)) {
606 trace_probe_log_set_index(0);
607 trace_probe_log_err(0, SAME_PROBE);
608 return -EEXIST;
609 }
610
611 /* Append to existing event */
612 ret = trace_probe_append(&tk->tp, &to->tp);
613 if (ret)
614 return ret;
615
616 /* Register k*probe */
617 ret = __register_trace_kprobe(tk);
618 if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
619 pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
620 ret = 0;
621 }
622
623 if (ret)
624 trace_probe_unlink(&tk->tp);
625 else
626 dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));
627
628 return ret;
629}
630
631/* Register a trace_probe and probe_event */
632static int register_trace_kprobe(struct trace_kprobe *tk)
633{
634 struct trace_kprobe *old_tk;
635 int ret;
636
637 mutex_lock(&event_mutex);
638
639 old_tk = find_trace_kprobe(trace_probe_name(&tk->tp),
640 trace_probe_group_name(&tk->tp));
641 if (old_tk) {
642 if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) {
643 trace_probe_log_set_index(0);
644 trace_probe_log_err(0, DIFF_PROBE_TYPE);
645 ret = -EEXIST;
646 } else {
647 ret = append_trace_kprobe(tk, old_tk);
648 }
649 goto end;
650 }
651
652 /* Register new event */
653 ret = register_kprobe_event(tk);
654 if (ret) {
655 if (ret == -EEXIST) {
656 trace_probe_log_set_index(0);
657 trace_probe_log_err(0, EVENT_EXIST);
658 } else
659 pr_warn("Failed to register probe event(%d)\n", ret);
660 goto end;
661 }
662
663 /* Register k*probe */
664 ret = __register_trace_kprobe(tk);
665 if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
666 pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
667 ret = 0;
668 }
669
670 if (ret < 0)
671 unregister_kprobe_event(tk);
672 else
673 dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));
674
675end:
676 mutex_unlock(&event_mutex);
677 return ret;
678}
679
680#ifdef CONFIG_MODULES
681/* Module notifier call back, checking event on the module */
682static int trace_kprobe_module_callback(struct notifier_block *nb,
683 unsigned long val, void *data)
684{
685 struct module *mod = data;
686 struct dyn_event *pos;
687 struct trace_kprobe *tk;
688 int ret;
689
690 if (val != MODULE_STATE_COMING)
691 return NOTIFY_DONE;
692
693 /* Update probes on coming module */
694 mutex_lock(&event_mutex);
695 for_each_trace_kprobe(tk, pos) {
696 if (trace_kprobe_within_module(tk, mod)) {
697 /* Don't need to check busy - this should have gone. */
698 __unregister_trace_kprobe(tk);
699 ret = __register_trace_kprobe(tk);
700 if (ret)
701 pr_warn("Failed to re-register probe %s on %s: %d\n",
702 trace_probe_name(&tk->tp),
703 module_name(mod), ret);
704 }
705 }
706 mutex_unlock(&event_mutex);
707
708 return NOTIFY_DONE;
709}
710
711static struct notifier_block trace_kprobe_module_nb = {
712 .notifier_call = trace_kprobe_module_callback,
713 .priority = 1 /* Invoked after kprobe module callback */
714};
715static int trace_kprobe_register_module_notifier(void)
716{
717 return register_module_notifier(&trace_kprobe_module_nb);
718}
719#else
720static int trace_kprobe_register_module_notifier(void)
721{
722 return 0;
723}
724#endif /* CONFIG_MODULES */
725
726static int count_symbols(void *data, unsigned long unused)
727{
728 unsigned int *count = data;
729
730 (*count)++;
731
732 return 0;
733}
734
735struct sym_count_ctx {
736 unsigned int count;
737 const char *name;
738};
739
740static int count_mod_symbols(void *data, const char *name, unsigned long unused)
741{
742 struct sym_count_ctx *ctx = data;
743
744 if (strcmp(name, ctx->name) == 0)
745 ctx->count++;
746
747 return 0;
748}
749
750static unsigned int number_of_same_symbols(char *func_name)
751{
752 struct sym_count_ctx ctx = { .count = 0, .name = func_name };
753
754 kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
755
756 module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx);
757
758 return ctx.count;
759}
760
761static int trace_kprobe_entry_handler(struct kretprobe_instance *ri,
762 struct pt_regs *regs);
763
764static int __trace_kprobe_create(int argc, const char *argv[])
765{
766 /*
767 * Argument syntax:
768 * - Add kprobe:
769 * p[:[GRP/][EVENT]] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
770 * - Add kretprobe:
771 * r[MAXACTIVE][:[GRP/][EVENT]] [MOD:]KSYM[+0] [FETCHARGS]
772 * Or
773 * p[:[GRP/][EVENT]] [MOD:]KSYM[+0]%return [FETCHARGS]
774 *
775 * Fetch args:
776 * $retval : fetch return value
777 * $stack : fetch stack address
778 * $stackN : fetch Nth of stack (N:0-)
779 * $comm : fetch current task comm
780 * @ADDR : fetch memory at ADDR (ADDR should be in kernel)
781 * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
782 * %REG : fetch register REG
783 * Dereferencing memory fetch:
784 * +|-offs(ARG) : fetch memory at ARG +|- offs address.
785 * Alias name of args:
786 * NAME=FETCHARG : set NAME as alias of FETCHARG.
787 * Type of args:
788 * FETCHARG:TYPE : use TYPE instead of unsigned long.
789 */
790 struct trace_kprobe *tk = NULL;
791 int i, len, new_argc = 0, ret = 0;
792 bool is_return = false;
793 char *symbol = NULL, *tmp = NULL;
794 const char **new_argv = NULL;
795 const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
796 enum probe_print_type ptype;
797 int maxactive = 0;
798 long offset = 0;
799 void *addr = NULL;
800 char buf[MAX_EVENT_NAME_LEN];
801 char gbuf[MAX_EVENT_NAME_LEN];
802 char abuf[MAX_BTF_ARGS_LEN];
803 char *dbuf = NULL;
804 struct traceprobe_parse_context ctx = { .flags = TPARG_FL_KERNEL };
805
806 switch (argv[0][0]) {
807 case 'r':
808 is_return = true;
809 break;
810 case 'p':
811 break;
812 default:
813 return -ECANCELED;
814 }
815 if (argc < 2)
816 return -ECANCELED;
817
818 trace_probe_log_init("trace_kprobe", argc, argv);
819
820 event = strchr(&argv[0][1], ':');
821 if (event)
822 event++;
823
824 if (isdigit(argv[0][1])) {
825 if (!is_return) {
826 trace_probe_log_err(1, BAD_MAXACT_TYPE);
827 goto parse_error;
828 }
829 if (event)
830 len = event - &argv[0][1] - 1;
831 else
832 len = strlen(&argv[0][1]);
833 if (len > MAX_EVENT_NAME_LEN - 1) {
834 trace_probe_log_err(1, BAD_MAXACT);
835 goto parse_error;
836 }
837 memcpy(buf, &argv[0][1], len);
838 buf[len] = '\0';
839 ret = kstrtouint(buf, 0, &maxactive);
840 if (ret || !maxactive) {
841 trace_probe_log_err(1, BAD_MAXACT);
842 goto parse_error;
843 }
844 /* kretprobes instances are iterated over via a list. The
845 * maximum should stay reasonable.
846 */
847 if (maxactive > KRETPROBE_MAXACTIVE_MAX) {
848 trace_probe_log_err(1, MAXACT_TOO_BIG);
849 goto parse_error;
850 }
851 }
852
853 /* try to parse an address. if that fails, try to read the
854 * input as a symbol. */
855 if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) {
856 trace_probe_log_set_index(1);
857 /* Check whether uprobe event specified */
858 if (strchr(argv[1], '/') && strchr(argv[1], ':')) {
859 ret = -ECANCELED;
860 goto error;
861 }
862 /* a symbol specified */
863 symbol = kstrdup(argv[1], GFP_KERNEL);
864 if (!symbol)
865 return -ENOMEM;
866
867 tmp = strchr(symbol, '%');
868 if (tmp) {
869 if (!strcmp(tmp, "%return")) {
870 *tmp = '\0';
871 is_return = true;
872 } else {
873 trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX);
874 goto parse_error;
875 }
876 }
877
878 /* TODO: support .init module functions */
879 ret = traceprobe_split_symbol_offset(symbol, &offset);
880 if (ret || offset < 0 || offset > UINT_MAX) {
881 trace_probe_log_err(0, BAD_PROBE_ADDR);
882 goto parse_error;
883 }
884 if (is_return)
885 ctx.flags |= TPARG_FL_RETURN;
886 ret = kprobe_on_func_entry(NULL, symbol, offset);
887 if (ret == 0 && !is_return)
888 ctx.flags |= TPARG_FL_FENTRY;
889 /* Defer the ENOENT case until register kprobe */
890 if (ret == -EINVAL && is_return) {
891 trace_probe_log_err(0, BAD_RETPROBE);
892 goto parse_error;
893 }
894 }
895
896 if (symbol && !strchr(symbol, ':')) {
897 unsigned int count;
898
899 count = number_of_same_symbols(symbol);
900 if (count > 1) {
901 /*
902 * Users should use ADDR to remove the ambiguity of
903 * using KSYM only.
904 */
905 trace_probe_log_err(0, NON_UNIQ_SYMBOL);
906 ret = -EADDRNOTAVAIL;
907
908 goto error;
909 } else if (count == 0) {
910 /*
911 * We can return ENOENT earlier than when register the
912 * kprobe.
913 */
914 trace_probe_log_err(0, BAD_PROBE_ADDR);
915 ret = -ENOENT;
916
917 goto error;
918 }
919 }
920
921 trace_probe_log_set_index(0);
922 if (event) {
923 ret = traceprobe_parse_event_name(&event, &group, gbuf,
924 event - argv[0]);
925 if (ret)
926 goto parse_error;
927 }
928
929 if (!event) {
930 /* Make a new event name */
931 if (symbol)
932 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
933 is_return ? 'r' : 'p', symbol, offset);
934 else
935 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
936 is_return ? 'r' : 'p', addr);
937 sanitize_event_name(buf);
938 event = buf;
939 }
940
941 argc -= 2; argv += 2;
942 ctx.funcname = symbol;
943 new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc,
944 abuf, MAX_BTF_ARGS_LEN, &ctx);
945 if (IS_ERR(new_argv)) {
946 ret = PTR_ERR(new_argv);
947 new_argv = NULL;
948 goto out;
949 }
950 if (new_argv) {
951 argc = new_argc;
952 argv = new_argv;
953 }
954
955 ret = traceprobe_expand_dentry_args(argc, argv, &dbuf);
956 if (ret)
957 goto out;
958
959 /* setup a probe */
960 tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,
961 argc, is_return);
962 if (IS_ERR(tk)) {
963 ret = PTR_ERR(tk);
964 /* This must return -ENOMEM, else there is a bug */
965 WARN_ON_ONCE(ret != -ENOMEM);
966 goto out; /* We know tk is not allocated */
967 }
968
969 /* parse arguments */
970 for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
971 trace_probe_log_set_index(i + 2);
972 ctx.offset = 0;
973 ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], &ctx);
974 if (ret)
975 goto error; /* This can be -ENOMEM */
976 }
977 /* entry handler for kretprobe */
978 if (is_return && tk->tp.entry_arg) {
979 tk->rp.entry_handler = trace_kprobe_entry_handler;
980 tk->rp.data_size = traceprobe_get_entry_data_size(&tk->tp);
981 }
982
983 ptype = is_return ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
984 ret = traceprobe_set_print_fmt(&tk->tp, ptype);
985 if (ret < 0)
986 goto error;
987
988 ret = register_trace_kprobe(tk);
989 if (ret) {
990 trace_probe_log_set_index(1);
991 if (ret == -EILSEQ)
992 trace_probe_log_err(0, BAD_INSN_BNDRY);
993 else if (ret == -ENOENT)
994 trace_probe_log_err(0, BAD_PROBE_ADDR);
995 else if (ret != -ENOMEM && ret != -EEXIST)
996 trace_probe_log_err(0, FAIL_REG_PROBE);
997 goto error;
998 }
999
1000out:
1001 traceprobe_finish_parse(&ctx);
1002 trace_probe_log_clear();
1003 kfree(new_argv);
1004 kfree(symbol);
1005 kfree(dbuf);
1006 return ret;
1007
1008parse_error:
1009 ret = -EINVAL;
1010error:
1011 free_trace_kprobe(tk);
1012 goto out;
1013}
1014
1015static int trace_kprobe_create(const char *raw_command)
1016{
1017 return trace_probe_create(raw_command, __trace_kprobe_create);
1018}
1019
1020static int create_or_delete_trace_kprobe(const char *raw_command)
1021{
1022 int ret;
1023
1024 if (raw_command[0] == '-')
1025 return dyn_event_release(raw_command, &trace_kprobe_ops);
1026
1027 ret = trace_kprobe_create(raw_command);
1028 return ret == -ECANCELED ? -EINVAL : ret;
1029}
1030
1031static int trace_kprobe_run_command(struct dynevent_cmd *cmd)
1032{
1033 return create_or_delete_trace_kprobe(cmd->seq.buffer);
1034}
1035
1036/**
1037 * kprobe_event_cmd_init - Initialize a kprobe event command object
1038 * @cmd: A pointer to the dynevent_cmd struct representing the new event
1039 * @buf: A pointer to the buffer used to build the command
1040 * @maxlen: The length of the buffer passed in @buf
1041 *
1042 * Initialize a synthetic event command object. Use this before
1043 * calling any of the other kprobe_event functions.
1044 */
1045void kprobe_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen)
1046{
1047 dynevent_cmd_init(cmd, buf, maxlen, DYNEVENT_TYPE_KPROBE,
1048 trace_kprobe_run_command);
1049}
1050EXPORT_SYMBOL_GPL(kprobe_event_cmd_init);
1051
1052/**
1053 * __kprobe_event_gen_cmd_start - Generate a kprobe event command from arg list
1054 * @cmd: A pointer to the dynevent_cmd struct representing the new event
1055 * @kretprobe: Is this a return probe?
1056 * @name: The name of the kprobe event
1057 * @loc: The location of the kprobe event
1058 * @...: Variable number of arg (pairs), one pair for each field
1059 *
1060 * NOTE: Users normally won't want to call this function directly, but
1061 * rather use the kprobe_event_gen_cmd_start() wrapper, which automatically
1062 * adds a NULL to the end of the arg list. If this function is used
1063 * directly, make sure the last arg in the variable arg list is NULL.
1064 *
1065 * Generate a kprobe event command to be executed by
1066 * kprobe_event_gen_cmd_end(). This function can be used to generate the
1067 * complete command or only the first part of it; in the latter case,
1068 * kprobe_event_add_fields() can be used to add more fields following this.
1069 *
1070 * Unlikely the synth_event_gen_cmd_start(), @loc must be specified. This
1071 * returns -EINVAL if @loc == NULL.
1072 *
1073 * Return: 0 if successful, error otherwise.
1074 */
1075int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd, bool kretprobe,
1076 const char *name, const char *loc, ...)
1077{
1078 char buf[MAX_EVENT_NAME_LEN];
1079 struct dynevent_arg arg;
1080 va_list args;
1081 int ret;
1082
1083 if (cmd->type != DYNEVENT_TYPE_KPROBE)
1084 return -EINVAL;
1085
1086 if (!loc)
1087 return -EINVAL;
1088
1089 if (kretprobe)
1090 snprintf(buf, MAX_EVENT_NAME_LEN, "r:kprobes/%s", name);
1091 else
1092 snprintf(buf, MAX_EVENT_NAME_LEN, "p:kprobes/%s", name);
1093
1094 ret = dynevent_str_add(cmd, buf);
1095 if (ret)
1096 return ret;
1097
1098 dynevent_arg_init(&arg, 0);
1099 arg.str = loc;
1100 ret = dynevent_arg_add(cmd, &arg, NULL);
1101 if (ret)
1102 return ret;
1103
1104 va_start(args, loc);
1105 for (;;) {
1106 const char *field;
1107
1108 field = va_arg(args, const char *);
1109 if (!field)
1110 break;
1111
1112 if (++cmd->n_fields > MAX_TRACE_ARGS) {
1113 ret = -EINVAL;
1114 break;
1115 }
1116
1117 arg.str = field;
1118 ret = dynevent_arg_add(cmd, &arg, NULL);
1119 if (ret)
1120 break;
1121 }
1122 va_end(args);
1123
1124 return ret;
1125}
1126EXPORT_SYMBOL_GPL(__kprobe_event_gen_cmd_start);
1127
1128/**
1129 * __kprobe_event_add_fields - Add probe fields to a kprobe command from arg list
1130 * @cmd: A pointer to the dynevent_cmd struct representing the new event
1131 * @...: Variable number of arg (pairs), one pair for each field
1132 *
1133 * NOTE: Users normally won't want to call this function directly, but
1134 * rather use the kprobe_event_add_fields() wrapper, which
1135 * automatically adds a NULL to the end of the arg list. If this
1136 * function is used directly, make sure the last arg in the variable
1137 * arg list is NULL.
1138 *
1139 * Add probe fields to an existing kprobe command using a variable
1140 * list of args. Fields are added in the same order they're listed.
1141 *
1142 * Return: 0 if successful, error otherwise.
1143 */
1144int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...)
1145{
1146 struct dynevent_arg arg;
1147 va_list args;
1148 int ret = 0;
1149
1150 if (cmd->type != DYNEVENT_TYPE_KPROBE)
1151 return -EINVAL;
1152
1153 dynevent_arg_init(&arg, 0);
1154
1155 va_start(args, cmd);
1156 for (;;) {
1157 const char *field;
1158
1159 field = va_arg(args, const char *);
1160 if (!field)
1161 break;
1162
1163 if (++cmd->n_fields > MAX_TRACE_ARGS) {
1164 ret = -EINVAL;
1165 break;
1166 }
1167
1168 arg.str = field;
1169 ret = dynevent_arg_add(cmd, &arg, NULL);
1170 if (ret)
1171 break;
1172 }
1173 va_end(args);
1174
1175 return ret;
1176}
1177EXPORT_SYMBOL_GPL(__kprobe_event_add_fields);
1178
1179/**
1180 * kprobe_event_delete - Delete a kprobe event
1181 * @name: The name of the kprobe event to delete
1182 *
1183 * Delete a kprobe event with the give @name from kernel code rather
1184 * than directly from the command line.
1185 *
1186 * Return: 0 if successful, error otherwise.
1187 */
1188int kprobe_event_delete(const char *name)
1189{
1190 char buf[MAX_EVENT_NAME_LEN];
1191
1192 snprintf(buf, MAX_EVENT_NAME_LEN, "-:%s", name);
1193
1194 return create_or_delete_trace_kprobe(buf);
1195}
1196EXPORT_SYMBOL_GPL(kprobe_event_delete);
1197
1198static int trace_kprobe_release(struct dyn_event *ev)
1199{
1200 struct trace_kprobe *tk = to_trace_kprobe(ev);
1201 int ret = unregister_trace_kprobe(tk);
1202
1203 if (!ret)
1204 free_trace_kprobe(tk);
1205 return ret;
1206}
1207
1208static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev)
1209{
1210 struct trace_kprobe *tk = to_trace_kprobe(ev);
1211 int i;
1212
1213 seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p');
1214 if (trace_kprobe_is_return(tk) && tk->rp.maxactive)
1215 seq_printf(m, "%d", tk->rp.maxactive);
1216 seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp),
1217 trace_probe_name(&tk->tp));
1218
1219 if (!tk->symbol)
1220 seq_printf(m, " 0x%p", tk->rp.kp.addr);
1221 else if (tk->rp.kp.offset)
1222 seq_printf(m, " %s+%u", trace_kprobe_symbol(tk),
1223 tk->rp.kp.offset);
1224 else
1225 seq_printf(m, " %s", trace_kprobe_symbol(tk));
1226
1227 for (i = 0; i < tk->tp.nr_args; i++)
1228 seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm);
1229 seq_putc(m, '\n');
1230
1231 return 0;
1232}
1233
1234static int probes_seq_show(struct seq_file *m, void *v)
1235{
1236 struct dyn_event *ev = v;
1237
1238 if (!is_trace_kprobe(ev))
1239 return 0;
1240
1241 return trace_kprobe_show(m, ev);
1242}
1243
1244static const struct seq_operations probes_seq_op = {
1245 .start = dyn_event_seq_start,
1246 .next = dyn_event_seq_next,
1247 .stop = dyn_event_seq_stop,
1248 .show = probes_seq_show
1249};
1250
1251static int probes_open(struct inode *inode, struct file *file)
1252{
1253 int ret;
1254
1255 ret = security_locked_down(LOCKDOWN_TRACEFS);
1256 if (ret)
1257 return ret;
1258
1259 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
1260 ret = dyn_events_release_all(&trace_kprobe_ops);
1261 if (ret < 0)
1262 return ret;
1263 }
1264
1265 return seq_open(file, &probes_seq_op);
1266}
1267
1268static ssize_t probes_write(struct file *file, const char __user *buffer,
1269 size_t count, loff_t *ppos)
1270{
1271 return trace_parse_run_command(file, buffer, count, ppos,
1272 create_or_delete_trace_kprobe);
1273}
1274
1275static const struct file_operations kprobe_events_ops = {
1276 .owner = THIS_MODULE,
1277 .open = probes_open,
1278 .read = seq_read,
1279 .llseek = seq_lseek,
1280 .release = seq_release,
1281 .write = probes_write,
1282};
1283
1284static unsigned long trace_kprobe_missed(struct trace_kprobe *tk)
1285{
1286 return trace_kprobe_is_return(tk) ?
1287 tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed;
1288}
1289
1290/* Probes profiling interfaces */
1291static int probes_profile_seq_show(struct seq_file *m, void *v)
1292{
1293 struct dyn_event *ev = v;
1294 struct trace_kprobe *tk;
1295 unsigned long nmissed;
1296
1297 if (!is_trace_kprobe(ev))
1298 return 0;
1299
1300 tk = to_trace_kprobe(ev);
1301 nmissed = trace_kprobe_missed(tk);
1302 seq_printf(m, " %-44s %15lu %15lu\n",
1303 trace_probe_name(&tk->tp),
1304 trace_kprobe_nhit(tk),
1305 nmissed);
1306
1307 return 0;
1308}
1309
1310static const struct seq_operations profile_seq_op = {
1311 .start = dyn_event_seq_start,
1312 .next = dyn_event_seq_next,
1313 .stop = dyn_event_seq_stop,
1314 .show = probes_profile_seq_show
1315};
1316
1317static int profile_open(struct inode *inode, struct file *file)
1318{
1319 int ret;
1320
1321 ret = security_locked_down(LOCKDOWN_TRACEFS);
1322 if (ret)
1323 return ret;
1324
1325 return seq_open(file, &profile_seq_op);
1326}
1327
1328static const struct file_operations kprobe_profile_ops = {
1329 .owner = THIS_MODULE,
1330 .open = profile_open,
1331 .read = seq_read,
1332 .llseek = seq_lseek,
1333 .release = seq_release,
1334};
1335
1336/* Note that we don't verify it, since the code does not come from user space */
1337static int
1338process_fetch_insn(struct fetch_insn *code, void *rec, void *edata,
1339 void *dest, void *base)
1340{
1341 struct pt_regs *regs = rec;
1342 unsigned long val;
1343 int ret;
1344
1345retry:
1346 /* 1st stage: get value from context */
1347 switch (code->op) {
1348 case FETCH_OP_REG:
1349 val = regs_get_register(regs, code->param);
1350 break;
1351 case FETCH_OP_STACK:
1352 val = regs_get_kernel_stack_nth(regs, code->param);
1353 break;
1354 case FETCH_OP_STACKP:
1355 val = kernel_stack_pointer(regs);
1356 break;
1357 case FETCH_OP_RETVAL:
1358 val = regs_return_value(regs);
1359 break;
1360#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
1361 case FETCH_OP_ARG:
1362 val = regs_get_kernel_argument(regs, code->param);
1363 break;
1364 case FETCH_OP_EDATA:
1365 val = *(unsigned long *)((unsigned long)edata + code->offset);
1366 break;
1367#endif
1368 case FETCH_NOP_SYMBOL: /* Ignore a place holder */
1369 code++;
1370 goto retry;
1371 default:
1372 ret = process_common_fetch_insn(code, &val);
1373 if (ret < 0)
1374 return ret;
1375 }
1376 code++;
1377
1378 return process_fetch_insn_bottom(code, val, dest, base);
1379}
1380NOKPROBE_SYMBOL(process_fetch_insn)
1381
1382/* Kprobe handler */
1383static nokprobe_inline void
1384__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
1385 struct trace_event_file *trace_file)
1386{
1387 struct kprobe_trace_entry_head *entry;
1388 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1389 struct trace_event_buffer fbuffer;
1390 int dsize;
1391
1392 WARN_ON(call != trace_file->event_call);
1393
1394 if (trace_trigger_soft_disabled(trace_file))
1395 return;
1396
1397 dsize = __get_data_size(&tk->tp, regs, NULL);
1398
1399 entry = trace_event_buffer_reserve(&fbuffer, trace_file,
1400 sizeof(*entry) + tk->tp.size + dsize);
1401 if (!entry)
1402 return;
1403
1404 fbuffer.regs = regs;
1405 entry->ip = (unsigned long)tk->rp.kp.addr;
1406 store_trace_args(&entry[1], &tk->tp, regs, NULL, sizeof(*entry), dsize);
1407
1408 trace_event_buffer_commit(&fbuffer);
1409}
1410
1411static void
1412kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs)
1413{
1414 struct event_file_link *link;
1415
1416 trace_probe_for_each_link_rcu(link, &tk->tp)
1417 __kprobe_trace_func(tk, regs, link->file);
1418}
1419NOKPROBE_SYMBOL(kprobe_trace_func);
1420
1421/* Kretprobe handler */
1422
1423static int trace_kprobe_entry_handler(struct kretprobe_instance *ri,
1424 struct pt_regs *regs)
1425{
1426 struct kretprobe *rp = get_kretprobe(ri);
1427 struct trace_kprobe *tk;
1428
1429 /*
1430 * There is a small chance that get_kretprobe(ri) returns NULL when
1431 * the kretprobe is unregister on another CPU between kretprobe's
1432 * trampoline_handler and this function.
1433 */
1434 if (unlikely(!rp))
1435 return -ENOENT;
1436
1437 tk = container_of(rp, struct trace_kprobe, rp);
1438
1439 /* store argument values into ri->data as entry data */
1440 if (tk->tp.entry_arg)
1441 store_trace_entry_data(ri->data, &tk->tp, regs);
1442
1443 return 0;
1444}
1445
1446
1447static nokprobe_inline void
1448__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
1449 struct pt_regs *regs,
1450 struct trace_event_file *trace_file)
1451{
1452 struct kretprobe_trace_entry_head *entry;
1453 struct trace_event_buffer fbuffer;
1454 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1455 int dsize;
1456
1457 WARN_ON(call != trace_file->event_call);
1458
1459 if (trace_trigger_soft_disabled(trace_file))
1460 return;
1461
1462 dsize = __get_data_size(&tk->tp, regs, ri->data);
1463
1464 entry = trace_event_buffer_reserve(&fbuffer, trace_file,
1465 sizeof(*entry) + tk->tp.size + dsize);
1466 if (!entry)
1467 return;
1468
1469 fbuffer.regs = regs;
1470 entry->func = (unsigned long)tk->rp.kp.addr;
1471 entry->ret_ip = get_kretprobe_retaddr(ri);
1472 store_trace_args(&entry[1], &tk->tp, regs, ri->data, sizeof(*entry), dsize);
1473
1474 trace_event_buffer_commit(&fbuffer);
1475}
1476
1477static void
1478kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
1479 struct pt_regs *regs)
1480{
1481 struct event_file_link *link;
1482
1483 trace_probe_for_each_link_rcu(link, &tk->tp)
1484 __kretprobe_trace_func(tk, ri, regs, link->file);
1485}
1486NOKPROBE_SYMBOL(kretprobe_trace_func);
1487
1488/* Event entry printers */
1489static enum print_line_t
1490print_kprobe_event(struct trace_iterator *iter, int flags,
1491 struct trace_event *event)
1492{
1493 struct kprobe_trace_entry_head *field;
1494 struct trace_seq *s = &iter->seq;
1495 struct trace_probe *tp;
1496
1497 field = (struct kprobe_trace_entry_head *)iter->ent;
1498 tp = trace_probe_primary_from_call(
1499 container_of(event, struct trace_event_call, event));
1500 if (WARN_ON_ONCE(!tp))
1501 goto out;
1502
1503 trace_seq_printf(s, "%s: (", trace_probe_name(tp));
1504
1505 if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
1506 goto out;
1507
1508 trace_seq_putc(s, ')');
1509
1510 if (trace_probe_print_args(s, tp->args, tp->nr_args,
1511 (u8 *)&field[1], field) < 0)
1512 goto out;
1513
1514 trace_seq_putc(s, '\n');
1515 out:
1516 return trace_handle_return(s);
1517}
1518
1519static enum print_line_t
1520print_kretprobe_event(struct trace_iterator *iter, int flags,
1521 struct trace_event *event)
1522{
1523 struct kretprobe_trace_entry_head *field;
1524 struct trace_seq *s = &iter->seq;
1525 struct trace_probe *tp;
1526
1527 field = (struct kretprobe_trace_entry_head *)iter->ent;
1528 tp = trace_probe_primary_from_call(
1529 container_of(event, struct trace_event_call, event));
1530 if (WARN_ON_ONCE(!tp))
1531 goto out;
1532
1533 trace_seq_printf(s, "%s: (", trace_probe_name(tp));
1534
1535 if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
1536 goto out;
1537
1538 trace_seq_puts(s, " <- ");
1539
1540 if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
1541 goto out;
1542
1543 trace_seq_putc(s, ')');
1544
1545 if (trace_probe_print_args(s, tp->args, tp->nr_args,
1546 (u8 *)&field[1], field) < 0)
1547 goto out;
1548
1549 trace_seq_putc(s, '\n');
1550
1551 out:
1552 return trace_handle_return(s);
1553}
1554
1555
1556static int kprobe_event_define_fields(struct trace_event_call *event_call)
1557{
1558 int ret;
1559 struct kprobe_trace_entry_head field;
1560 struct trace_probe *tp;
1561
1562 tp = trace_probe_primary_from_call(event_call);
1563 if (WARN_ON_ONCE(!tp))
1564 return -ENOENT;
1565
1566 DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
1567
1568 return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
1569}
1570
1571static int kretprobe_event_define_fields(struct trace_event_call *event_call)
1572{
1573 int ret;
1574 struct kretprobe_trace_entry_head field;
1575 struct trace_probe *tp;
1576
1577 tp = trace_probe_primary_from_call(event_call);
1578 if (WARN_ON_ONCE(!tp))
1579 return -ENOENT;
1580
1581 DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
1582 DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
1583
1584 return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
1585}
1586
1587#ifdef CONFIG_PERF_EVENTS
1588
1589/* Kprobe profile handler */
1590static int
1591kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
1592{
1593 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1594 struct kprobe_trace_entry_head *entry;
1595 struct hlist_head *head;
1596 int size, __size, dsize;
1597 int rctx;
1598
1599 if (bpf_prog_array_valid(call)) {
1600 unsigned long orig_ip = instruction_pointer(regs);
1601 int ret;
1602
1603 ret = trace_call_bpf(call, regs);
1604
1605 /*
1606 * We need to check and see if we modified the pc of the
1607 * pt_regs, and if so return 1 so that we don't do the
1608 * single stepping.
1609 */
1610 if (orig_ip != instruction_pointer(regs))
1611 return 1;
1612 if (!ret)
1613 return 0;
1614 }
1615
1616 head = this_cpu_ptr(call->perf_events);
1617 if (hlist_empty(head))
1618 return 0;
1619
1620 dsize = __get_data_size(&tk->tp, regs, NULL);
1621 __size = sizeof(*entry) + tk->tp.size + dsize;
1622 size = ALIGN(__size + sizeof(u32), sizeof(u64));
1623 size -= sizeof(u32);
1624
1625 entry = perf_trace_buf_alloc(size, NULL, &rctx);
1626 if (!entry)
1627 return 0;
1628
1629 entry->ip = (unsigned long)tk->rp.kp.addr;
1630 memset(&entry[1], 0, dsize);
1631 store_trace_args(&entry[1], &tk->tp, regs, NULL, sizeof(*entry), dsize);
1632 perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
1633 head, NULL);
1634 return 0;
1635}
1636NOKPROBE_SYMBOL(kprobe_perf_func);
1637
1638/* Kretprobe profile handler */
1639static void
1640kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
1641 struct pt_regs *regs)
1642{
1643 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1644 struct kretprobe_trace_entry_head *entry;
1645 struct hlist_head *head;
1646 int size, __size, dsize;
1647 int rctx;
1648
1649 if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
1650 return;
1651
1652 head = this_cpu_ptr(call->perf_events);
1653 if (hlist_empty(head))
1654 return;
1655
1656 dsize = __get_data_size(&tk->tp, regs, ri->data);
1657 __size = sizeof(*entry) + tk->tp.size + dsize;
1658 size = ALIGN(__size + sizeof(u32), sizeof(u64));
1659 size -= sizeof(u32);
1660
1661 entry = perf_trace_buf_alloc(size, NULL, &rctx);
1662 if (!entry)
1663 return;
1664
1665 entry->func = (unsigned long)tk->rp.kp.addr;
1666 entry->ret_ip = get_kretprobe_retaddr(ri);
1667 store_trace_args(&entry[1], &tk->tp, regs, ri->data, sizeof(*entry), dsize);
1668 perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
1669 head, NULL);
1670}
1671NOKPROBE_SYMBOL(kretprobe_perf_func);
1672
1673int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type,
1674 const char **symbol, u64 *probe_offset,
1675 u64 *probe_addr, unsigned long *missed,
1676 bool perf_type_tracepoint)
1677{
1678 const char *pevent = trace_event_name(event->tp_event);
1679 const char *group = event->tp_event->class->system;
1680 struct trace_kprobe *tk;
1681
1682 if (perf_type_tracepoint)
1683 tk = find_trace_kprobe(pevent, group);
1684 else
1685 tk = trace_kprobe_primary_from_call(event->tp_event);
1686 if (!tk)
1687 return -EINVAL;
1688
1689 *fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE
1690 : BPF_FD_TYPE_KPROBE;
1691 *probe_offset = tk->rp.kp.offset;
1692 *probe_addr = kallsyms_show_value(current_cred()) ?
1693 (unsigned long)tk->rp.kp.addr : 0;
1694 *symbol = tk->symbol;
1695 if (missed)
1696 *missed = trace_kprobe_missed(tk);
1697 return 0;
1698}
1699#endif /* CONFIG_PERF_EVENTS */
1700
1701/*
1702 * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex.
1703 *
1704 * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe
1705 * lockless, but we can't race with this __init function.
1706 */
1707static int kprobe_register(struct trace_event_call *event,
1708 enum trace_reg type, void *data)
1709{
1710 struct trace_event_file *file = data;
1711
1712 switch (type) {
1713 case TRACE_REG_REGISTER:
1714 return enable_trace_kprobe(event, file);
1715 case TRACE_REG_UNREGISTER:
1716 return disable_trace_kprobe(event, file);
1717
1718#ifdef CONFIG_PERF_EVENTS
1719 case TRACE_REG_PERF_REGISTER:
1720 return enable_trace_kprobe(event, NULL);
1721 case TRACE_REG_PERF_UNREGISTER:
1722 return disable_trace_kprobe(event, NULL);
1723 case TRACE_REG_PERF_OPEN:
1724 case TRACE_REG_PERF_CLOSE:
1725 case TRACE_REG_PERF_ADD:
1726 case TRACE_REG_PERF_DEL:
1727 return 0;
1728#endif
1729 }
1730 return 0;
1731}
1732
1733static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
1734{
1735 struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp);
1736 int ret = 0;
1737
1738 raw_cpu_inc(*tk->nhit);
1739
1740 if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
1741 kprobe_trace_func(tk, regs);
1742#ifdef CONFIG_PERF_EVENTS
1743 if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
1744 ret = kprobe_perf_func(tk, regs);
1745#endif
1746 return ret;
1747}
1748NOKPROBE_SYMBOL(kprobe_dispatcher);
1749
1750static int
1751kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
1752{
1753 struct kretprobe *rp = get_kretprobe(ri);
1754 struct trace_kprobe *tk;
1755
1756 /*
1757 * There is a small chance that get_kretprobe(ri) returns NULL when
1758 * the kretprobe is unregister on another CPU between kretprobe's
1759 * trampoline_handler and this function.
1760 */
1761 if (unlikely(!rp))
1762 return 0;
1763
1764 tk = container_of(rp, struct trace_kprobe, rp);
1765 raw_cpu_inc(*tk->nhit);
1766
1767 if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
1768 kretprobe_trace_func(tk, ri, regs);
1769#ifdef CONFIG_PERF_EVENTS
1770 if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
1771 kretprobe_perf_func(tk, ri, regs);
1772#endif
1773 return 0; /* We don't tweak kernel, so just return 0 */
1774}
1775NOKPROBE_SYMBOL(kretprobe_dispatcher);
1776
1777static struct trace_event_functions kretprobe_funcs = {
1778 .trace = print_kretprobe_event
1779};
1780
1781static struct trace_event_functions kprobe_funcs = {
1782 .trace = print_kprobe_event
1783};
1784
1785static struct trace_event_fields kretprobe_fields_array[] = {
1786 { .type = TRACE_FUNCTION_TYPE,
1787 .define_fields = kretprobe_event_define_fields },
1788 {}
1789};
1790
1791static struct trace_event_fields kprobe_fields_array[] = {
1792 { .type = TRACE_FUNCTION_TYPE,
1793 .define_fields = kprobe_event_define_fields },
1794 {}
1795};
1796
1797static inline void init_trace_event_call(struct trace_kprobe *tk)
1798{
1799 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1800
1801 if (trace_kprobe_is_return(tk)) {
1802 call->event.funcs = &kretprobe_funcs;
1803 call->class->fields_array = kretprobe_fields_array;
1804 } else {
1805 call->event.funcs = &kprobe_funcs;
1806 call->class->fields_array = kprobe_fields_array;
1807 }
1808
1809 call->flags = TRACE_EVENT_FL_KPROBE;
1810 call->class->reg = kprobe_register;
1811}
1812
1813static int register_kprobe_event(struct trace_kprobe *tk)
1814{
1815 init_trace_event_call(tk);
1816
1817 return trace_probe_register_event_call(&tk->tp);
1818}
1819
1820static int unregister_kprobe_event(struct trace_kprobe *tk)
1821{
1822 return trace_probe_unregister_event_call(&tk->tp);
1823}
1824
1825#ifdef CONFIG_PERF_EVENTS
1826
1827/* create a trace_kprobe, but don't add it to global lists */
1828struct trace_event_call *
1829create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
1830 bool is_return)
1831{
1832 enum probe_print_type ptype;
1833 struct trace_kprobe *tk;
1834 int ret;
1835 char *event;
1836
1837 if (func) {
1838 unsigned int count;
1839
1840 count = number_of_same_symbols(func);
1841 if (count > 1)
1842 /*
1843 * Users should use addr to remove the ambiguity of
1844 * using func only.
1845 */
1846 return ERR_PTR(-EADDRNOTAVAIL);
1847 else if (count == 0)
1848 /*
1849 * We can return ENOENT earlier than when register the
1850 * kprobe.
1851 */
1852 return ERR_PTR(-ENOENT);
1853 }
1854
1855 /*
1856 * local trace_kprobes are not added to dyn_event, so they are never
1857 * searched in find_trace_kprobe(). Therefore, there is no concern of
1858 * duplicated name here.
1859 */
1860 event = func ? func : "DUMMY_EVENT";
1861
1862 tk = alloc_trace_kprobe(KPROBE_EVENT_SYSTEM, event, (void *)addr, func,
1863 offs, 0 /* maxactive */, 0 /* nargs */,
1864 is_return);
1865
1866 if (IS_ERR(tk)) {
1867 pr_info("Failed to allocate trace_probe.(%d)\n",
1868 (int)PTR_ERR(tk));
1869 return ERR_CAST(tk);
1870 }
1871
1872 init_trace_event_call(tk);
1873
1874 ptype = trace_kprobe_is_return(tk) ?
1875 PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
1876 if (traceprobe_set_print_fmt(&tk->tp, ptype) < 0) {
1877 ret = -ENOMEM;
1878 goto error;
1879 }
1880
1881 ret = __register_trace_kprobe(tk);
1882 if (ret < 0)
1883 goto error;
1884
1885 return trace_probe_event_call(&tk->tp);
1886error:
1887 free_trace_kprobe(tk);
1888 return ERR_PTR(ret);
1889}
1890
1891void destroy_local_trace_kprobe(struct trace_event_call *event_call)
1892{
1893 struct trace_kprobe *tk;
1894
1895 tk = trace_kprobe_primary_from_call(event_call);
1896 if (unlikely(!tk))
1897 return;
1898
1899 if (trace_probe_is_enabled(&tk->tp)) {
1900 WARN_ON(1);
1901 return;
1902 }
1903
1904 __unregister_trace_kprobe(tk);
1905
1906 free_trace_kprobe(tk);
1907}
1908#endif /* CONFIG_PERF_EVENTS */
1909
1910static __init void enable_boot_kprobe_events(void)
1911{
1912 struct trace_array *tr = top_trace_array();
1913 struct trace_event_file *file;
1914 struct trace_kprobe *tk;
1915 struct dyn_event *pos;
1916
1917 mutex_lock(&event_mutex);
1918 for_each_trace_kprobe(tk, pos) {
1919 list_for_each_entry(file, &tr->events, list)
1920 if (file->event_call == trace_probe_event_call(&tk->tp))
1921 trace_event_enable_disable(file, 1, 0);
1922 }
1923 mutex_unlock(&event_mutex);
1924}
1925
1926static __init void setup_boot_kprobe_events(void)
1927{
1928 char *p, *cmd = kprobe_boot_events_buf;
1929 int ret;
1930
1931 strreplace(kprobe_boot_events_buf, ',', ' ');
1932
1933 while (cmd && *cmd != '\0') {
1934 p = strchr(cmd, ';');
1935 if (p)
1936 *p++ = '\0';
1937
1938 ret = create_or_delete_trace_kprobe(cmd);
1939 if (ret)
1940 pr_warn("Failed to add event(%d): %s\n", ret, cmd);
1941
1942 cmd = p;
1943 }
1944
1945 enable_boot_kprobe_events();
1946}
1947
1948/*
1949 * Register dynevent at core_initcall. This allows kernel to setup kprobe
1950 * events in postcore_initcall without tracefs.
1951 */
1952static __init int init_kprobe_trace_early(void)
1953{
1954 int ret;
1955
1956 ret = dyn_event_register(&trace_kprobe_ops);
1957 if (ret)
1958 return ret;
1959
1960 if (trace_kprobe_register_module_notifier())
1961 return -EINVAL;
1962
1963 return 0;
1964}
1965core_initcall(init_kprobe_trace_early);
1966
1967/* Make a tracefs interface for controlling probe points */
1968static __init int init_kprobe_trace(void)
1969{
1970 int ret;
1971
1972 ret = tracing_init_dentry();
1973 if (ret)
1974 return 0;
1975
1976 /* Event list interface */
1977 trace_create_file("kprobe_events", TRACE_MODE_WRITE,
1978 NULL, NULL, &kprobe_events_ops);
1979
1980 /* Profile interface */
1981 trace_create_file("kprobe_profile", TRACE_MODE_READ,
1982 NULL, NULL, &kprobe_profile_ops);
1983
1984 setup_boot_kprobe_events();
1985
1986 return 0;
1987}
1988fs_initcall(init_kprobe_trace);
1989
1990
1991#ifdef CONFIG_FTRACE_STARTUP_TEST
1992static __init struct trace_event_file *
1993find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
1994{
1995 struct trace_event_file *file;
1996
1997 list_for_each_entry(file, &tr->events, list)
1998 if (file->event_call == trace_probe_event_call(&tk->tp))
1999 return file;
2000
2001 return NULL;
2002}
2003
2004/*
2005 * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this
2006 * stage, we can do this lockless.
2007 */
2008static __init int kprobe_trace_self_tests_init(void)
2009{
2010 int ret, warn = 0;
2011 int (*target)(int, int, int, int, int, int);
2012 struct trace_kprobe *tk;
2013 struct trace_event_file *file;
2014
2015 if (tracing_is_disabled())
2016 return -ENODEV;
2017
2018 if (tracing_selftest_disabled)
2019 return 0;
2020
2021 target = kprobe_trace_selftest_target;
2022
2023 pr_info("Testing kprobe tracing: ");
2024
2025 ret = create_or_delete_trace_kprobe("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)");
2026 if (WARN_ON_ONCE(ret)) {
2027 pr_warn("error on probing function entry.\n");
2028 warn++;
2029 } else {
2030 /* Enable trace point */
2031 tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
2032 if (WARN_ON_ONCE(tk == NULL)) {
2033 pr_warn("error on getting new probe.\n");
2034 warn++;
2035 } else {
2036 file = find_trace_probe_file(tk, top_trace_array());
2037 if (WARN_ON_ONCE(file == NULL)) {
2038 pr_warn("error on getting probe file.\n");
2039 warn++;
2040 } else
2041 enable_trace_kprobe(
2042 trace_probe_event_call(&tk->tp), file);
2043 }
2044 }
2045
2046 ret = create_or_delete_trace_kprobe("r:testprobe2 kprobe_trace_selftest_target $retval");
2047 if (WARN_ON_ONCE(ret)) {
2048 pr_warn("error on probing function return.\n");
2049 warn++;
2050 } else {
2051 /* Enable trace point */
2052 tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
2053 if (WARN_ON_ONCE(tk == NULL)) {
2054 pr_warn("error on getting 2nd new probe.\n");
2055 warn++;
2056 } else {
2057 file = find_trace_probe_file(tk, top_trace_array());
2058 if (WARN_ON_ONCE(file == NULL)) {
2059 pr_warn("error on getting probe file.\n");
2060 warn++;
2061 } else
2062 enable_trace_kprobe(
2063 trace_probe_event_call(&tk->tp), file);
2064 }
2065 }
2066
2067 if (warn)
2068 goto end;
2069
2070 ret = target(1, 2, 3, 4, 5, 6);
2071
2072 /*
2073 * Not expecting an error here, the check is only to prevent the
2074 * optimizer from removing the call to target() as otherwise there
2075 * are no side-effects and the call is never performed.
2076 */
2077 if (ret != 21)
2078 warn++;
2079
2080 /* Disable trace points before removing it */
2081 tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
2082 if (WARN_ON_ONCE(tk == NULL)) {
2083 pr_warn("error on getting test probe.\n");
2084 warn++;
2085 } else {
2086 if (trace_kprobe_nhit(tk) != 1) {
2087 pr_warn("incorrect number of testprobe hits\n");
2088 warn++;
2089 }
2090
2091 file = find_trace_probe_file(tk, top_trace_array());
2092 if (WARN_ON_ONCE(file == NULL)) {
2093 pr_warn("error on getting probe file.\n");
2094 warn++;
2095 } else
2096 disable_trace_kprobe(
2097 trace_probe_event_call(&tk->tp), file);
2098 }
2099
2100 tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
2101 if (WARN_ON_ONCE(tk == NULL)) {
2102 pr_warn("error on getting 2nd test probe.\n");
2103 warn++;
2104 } else {
2105 if (trace_kprobe_nhit(tk) != 1) {
2106 pr_warn("incorrect number of testprobe2 hits\n");
2107 warn++;
2108 }
2109
2110 file = find_trace_probe_file(tk, top_trace_array());
2111 if (WARN_ON_ONCE(file == NULL)) {
2112 pr_warn("error on getting probe file.\n");
2113 warn++;
2114 } else
2115 disable_trace_kprobe(
2116 trace_probe_event_call(&tk->tp), file);
2117 }
2118
2119 ret = create_or_delete_trace_kprobe("-:testprobe");
2120 if (WARN_ON_ONCE(ret)) {
2121 pr_warn("error on deleting a probe.\n");
2122 warn++;
2123 }
2124
2125 ret = create_or_delete_trace_kprobe("-:testprobe2");
2126 if (WARN_ON_ONCE(ret)) {
2127 pr_warn("error on deleting a probe.\n");
2128 warn++;
2129 }
2130
2131end:
2132 ret = dyn_events_release_all(&trace_kprobe_ops);
2133 if (WARN_ON_ONCE(ret)) {
2134 pr_warn("error on cleaning up probes.\n");
2135 warn++;
2136 }
2137 /*
2138 * Wait for the optimizer work to finish. Otherwise it might fiddle
2139 * with probes in already freed __init text.
2140 */
2141 wait_for_kprobe_optimizer();
2142 if (warn)
2143 pr_cont("NG: Some tests are failed. Please check them.\n");
2144 else
2145 pr_cont("OK\n");
2146 return 0;
2147}
2148
2149late_initcall(kprobe_trace_self_tests_init);
2150
2151#endif
Linux 6.x block layer and io_uring tree(s)