1 // SPDX-License-Identifier: GPL-2.0
3 * Kprobes-based tracing events
5 * Created by Masami Hiramatsu <mhiramat@redhat.com>
8 #define pr_fmt(fmt) "trace_kprobe: " fmt
10 #include <linux/security.h>
11 #include <linux/module.h>
12 #include <linux/uaccess.h>
13 #include <linux/rculist.h>
14 #include <linux/error-injection.h>
16 #include <asm/setup.h> /* for COMMAND_LINE_SIZE */
18 #include "trace_dynevent.h"
19 #include "trace_kprobe_selftest.h"
20 #include "trace_probe.h"
21 #include "trace_probe_tmpl.h"
23 #define KPROBE_EVENT_SYSTEM "kprobes"
24 #define KRETPROBE_MAXACTIVE_MAX 4096
25 #define MAX_KPROBE_CMDLINE_SIZE 1024
27 /* Kprobe early definition from command line */
28 static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata;
29 static bool kprobe_boot_events_enabled __initdata;
31 static int __init set_kprobe_boot_events(char *str)
33 strlcpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE);
36 __setup("kprobe_event=", set_kprobe_boot_events);
38 static int trace_kprobe_create(int argc, const char **argv);
39 static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev);
40 static int trace_kprobe_release(struct dyn_event *ev);
41 static bool trace_kprobe_is_busy(struct dyn_event *ev);
42 static bool trace_kprobe_match(const char *system, const char *event,
43 int argc, const char **argv, struct dyn_event *ev);
45 static struct dyn_event_operations trace_kprobe_ops = {
46 .create = trace_kprobe_create,
47 .show = trace_kprobe_show,
48 .is_busy = trace_kprobe_is_busy,
49 .free = trace_kprobe_release,
50 .match = trace_kprobe_match,
54 * Kprobe event core functions
57 struct dyn_event devent;
58 struct kretprobe rp; /* Use rp.kp for kprobe use */
59 unsigned long __percpu *nhit;
60 const char *symbol; /* symbol name */
61 struct trace_probe tp;
64 static bool is_trace_kprobe(struct dyn_event *ev)
66 return ev->ops == &trace_kprobe_ops;
69 static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev)
71 return container_of(ev, struct trace_kprobe, devent);
75 * for_each_trace_kprobe - iterate over the trace_kprobe list
76 * @pos: the struct trace_kprobe * for each entry
77 * @dpos: the struct dyn_event * to use as a loop cursor
79 #define for_each_trace_kprobe(pos, dpos) \
80 for_each_dyn_event(dpos) \
81 if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos)))
83 #define SIZEOF_TRACE_KPROBE(n) \
84 (offsetof(struct trace_kprobe, tp.args) + \
85 (sizeof(struct probe_arg) * (n)))
87 static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
89 return tk->rp.handler != NULL;
92 static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk)
94 return tk->symbol ? tk->symbol : "unknown";
97 static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk)
99 return tk->rp.kp.offset;
102 static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk)
104 return !!(kprobe_gone(&tk->rp.kp));
107 static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk,
110 int len = strlen(mod->name);
111 const char *name = trace_kprobe_symbol(tk);
112 return strncmp(mod->name, name, len) == 0 && name[len] == ':';
115 static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
122 p = strchr(tk->symbol, ':');
126 mutex_lock(&module_mutex);
127 ret = !!find_module(tk->symbol);
128 mutex_unlock(&module_mutex);
134 static bool trace_kprobe_is_busy(struct dyn_event *ev)
136 struct trace_kprobe *tk = to_trace_kprobe(ev);
138 return trace_probe_is_enabled(&tk->tp);
141 static bool trace_kprobe_match_command_head(struct trace_kprobe *tk,
142 int argc, const char **argv)
144 char buf[MAX_ARGSTR_LEN + 1];
150 snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr);
151 else if (tk->rp.kp.offset)
152 snprintf(buf, sizeof(buf), "%s+%u",
153 trace_kprobe_symbol(tk), tk->rp.kp.offset);
155 snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk));
156 if (strcmp(buf, argv[0]))
160 return trace_probe_match_command_args(&tk->tp, argc, argv);
163 static bool trace_kprobe_match(const char *system, const char *event,
164 int argc, const char **argv, struct dyn_event *ev)
166 struct trace_kprobe *tk = to_trace_kprobe(ev);
168 return strcmp(trace_probe_name(&tk->tp), event) == 0 &&
169 (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) &&
170 trace_kprobe_match_command_head(tk, argc, argv);
173 static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
175 unsigned long nhit = 0;
178 for_each_possible_cpu(cpu)
179 nhit += *per_cpu_ptr(tk->nhit, cpu);
184 static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk)
186 return !(list_empty(&tk->rp.kp.list) &&
187 hlist_unhashed(&tk->rp.kp.hlist));
190 /* Return 0 if it fails to find the symbol address */
191 static nokprobe_inline
192 unsigned long trace_kprobe_address(struct trace_kprobe *tk)
197 addr = (unsigned long)
198 kallsyms_lookup_name(trace_kprobe_symbol(tk));
200 addr += tk->rp.kp.offset;
202 addr = (unsigned long)tk->rp.kp.addr;
207 static nokprobe_inline struct trace_kprobe *
208 trace_kprobe_primary_from_call(struct trace_event_call *call)
210 struct trace_probe *tp;
212 tp = trace_probe_primary_from_call(call);
213 if (WARN_ON_ONCE(!tp))
216 return container_of(tp, struct trace_kprobe, tp);
219 bool trace_kprobe_on_func_entry(struct trace_event_call *call)
221 struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
223 return tk ? kprobe_on_func_entry(tk->rp.kp.addr,
224 tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name,
225 tk->rp.kp.addr ? 0 : tk->rp.kp.offset) : false;
228 bool trace_kprobe_error_injectable(struct trace_event_call *call)
230 struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
232 return tk ? within_error_injection_list(trace_kprobe_address(tk)) :
236 static int register_kprobe_event(struct trace_kprobe *tk);
237 static int unregister_kprobe_event(struct trace_kprobe *tk);
239 static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
240 static int kretprobe_dispatcher(struct kretprobe_instance *ri,
241 struct pt_regs *regs);
243 static void free_trace_kprobe(struct trace_kprobe *tk)
246 trace_probe_cleanup(&tk->tp);
248 free_percpu(tk->nhit);
254 * Allocate new trace_probe and initialize it (including kprobes).
256 static struct trace_kprobe *alloc_trace_kprobe(const char *group,
262 int nargs, bool is_return)
264 struct trace_kprobe *tk;
267 tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL);
271 tk->nhit = alloc_percpu(unsigned long);
276 tk->symbol = kstrdup(symbol, GFP_KERNEL);
279 tk->rp.kp.symbol_name = tk->symbol;
280 tk->rp.kp.offset = offs;
282 tk->rp.kp.addr = addr;
285 tk->rp.handler = kretprobe_dispatcher;
287 tk->rp.kp.pre_handler = kprobe_dispatcher;
289 tk->rp.maxactive = maxactive;
290 INIT_HLIST_NODE(&tk->rp.kp.hlist);
291 INIT_LIST_HEAD(&tk->rp.kp.list);
293 ret = trace_probe_init(&tk->tp, event, group);
297 dyn_event_init(&tk->devent, &trace_kprobe_ops);
300 free_trace_kprobe(tk);
304 static struct trace_kprobe *find_trace_kprobe(const char *event,
307 struct dyn_event *pos;
308 struct trace_kprobe *tk;
310 for_each_trace_kprobe(tk, pos)
311 if (strcmp(trace_probe_name(&tk->tp), event) == 0 &&
312 strcmp(trace_probe_group_name(&tk->tp), group) == 0)
317 static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
321 if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) {
322 if (trace_kprobe_is_return(tk))
323 ret = enable_kretprobe(&tk->rp);
325 ret = enable_kprobe(&tk->rp.kp);
331 static void __disable_trace_kprobe(struct trace_probe *tp)
333 struct trace_probe *pos;
334 struct trace_kprobe *tk;
336 list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
337 tk = container_of(pos, struct trace_kprobe, tp);
338 if (!trace_kprobe_is_registered(tk))
340 if (trace_kprobe_is_return(tk))
341 disable_kretprobe(&tk->rp);
343 disable_kprobe(&tk->rp.kp);
349 * if the file is NULL, enable "perf" handler, or enable "trace" handler.
351 static int enable_trace_kprobe(struct trace_event_call *call,
352 struct trace_event_file *file)
354 struct trace_probe *pos, *tp;
355 struct trace_kprobe *tk;
359 tp = trace_probe_primary_from_call(call);
360 if (WARN_ON_ONCE(!tp))
362 enabled = trace_probe_is_enabled(tp);
364 /* This also changes "enabled" state */
366 ret = trace_probe_add_file(tp, file);
370 trace_probe_set_flag(tp, TP_FLAG_PROFILE);
375 list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
376 tk = container_of(pos, struct trace_kprobe, tp);
377 if (trace_kprobe_has_gone(tk))
379 ret = __enable_trace_kprobe(tk);
386 /* Failed to enable one of them. Roll back all */
388 __disable_trace_kprobe(tp);
390 trace_probe_remove_file(tp, file);
392 trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
399 * Disable trace_probe
400 * if the file is NULL, disable "perf" handler, or disable "trace" handler.
402 static int disable_trace_kprobe(struct trace_event_call *call,
403 struct trace_event_file *file)
405 struct trace_probe *tp;
407 tp = trace_probe_primary_from_call(call);
408 if (WARN_ON_ONCE(!tp))
412 if (!trace_probe_get_file_link(tp, file))
414 if (!trace_probe_has_single_file(tp))
416 trace_probe_clear_flag(tp, TP_FLAG_TRACE);
418 trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
420 if (!trace_probe_is_enabled(tp))
421 __disable_trace_kprobe(tp);
426 * Synchronization is done in below function. For perf event,
427 * file == NULL and perf_trace_event_unreg() calls
428 * tracepoint_synchronize_unregister() to ensure synchronize
429 * event. We don't need to care about it.
431 trace_probe_remove_file(tp, file);
436 #if defined(CONFIG_KPROBES_ON_FTRACE) && \
437 !defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE)
438 static bool __within_notrace_func(unsigned long addr)
440 unsigned long offset, size;
442 if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset))
445 /* Get the entry address of the target function */
449 * Since ftrace_location_range() does inclusive range check, we need
450 * to subtract 1 byte from the end address.
452 return !ftrace_location_range(addr, addr + size - 1);
455 static bool within_notrace_func(struct trace_kprobe *tk)
457 unsigned long addr = addr = trace_kprobe_address(tk);
458 char symname[KSYM_NAME_LEN], *p;
460 if (!__within_notrace_func(addr))
463 /* Check if the address is on a suffixed-symbol */
464 if (!lookup_symbol_name(addr, symname)) {
465 p = strchr(symname, '.');
469 addr = (unsigned long)kprobe_lookup_name(symname, 0);
471 return __within_notrace_func(addr);
477 #define within_notrace_func(tk) (false)
480 /* Internal register function - just handle k*probes and flags */
481 static int __register_trace_kprobe(struct trace_kprobe *tk)
485 ret = security_locked_down(LOCKDOWN_KPROBES);
489 if (trace_kprobe_is_registered(tk))
492 if (within_notrace_func(tk)) {
493 pr_warn("Could not probe notrace function %s\n",
494 trace_kprobe_symbol(tk));
498 for (i = 0; i < tk->tp.nr_args; i++) {
499 ret = traceprobe_update_arg(&tk->tp.args[i]);
504 /* Set/clear disabled flag according to tp->flag */
505 if (trace_probe_is_enabled(&tk->tp))
506 tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
508 tk->rp.kp.flags |= KPROBE_FLAG_DISABLED;
510 if (trace_kprobe_is_return(tk))
511 ret = register_kretprobe(&tk->rp);
513 ret = register_kprobe(&tk->rp.kp);
518 /* Internal unregister function - just handle k*probes and flags */
519 static void __unregister_trace_kprobe(struct trace_kprobe *tk)
521 if (trace_kprobe_is_registered(tk)) {
522 if (trace_kprobe_is_return(tk))
523 unregister_kretprobe(&tk->rp);
525 unregister_kprobe(&tk->rp.kp);
526 /* Cleanup kprobe for reuse and mark it unregistered */
527 INIT_HLIST_NODE(&tk->rp.kp.hlist);
528 INIT_LIST_HEAD(&tk->rp.kp.list);
529 if (tk->rp.kp.symbol_name)
530 tk->rp.kp.addr = NULL;
534 /* Unregister a trace_probe and probe_event */
535 static int unregister_trace_kprobe(struct trace_kprobe *tk)
537 /* If other probes are on the event, just unregister kprobe */
538 if (trace_probe_has_sibling(&tk->tp))
541 /* Enabled event can not be unregistered */
542 if (trace_probe_is_enabled(&tk->tp))
545 /* Will fail if probe is being used by ftrace or perf */
546 if (unregister_kprobe_event(tk))
550 __unregister_trace_kprobe(tk);
551 dyn_event_remove(&tk->devent);
552 trace_probe_unlink(&tk->tp);
557 static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
558 struct trace_kprobe *comp)
560 struct trace_probe_event *tpe = orig->tp.event;
561 struct trace_probe *pos;
564 list_for_each_entry(pos, &tpe->probes, list) {
565 orig = container_of(pos, struct trace_kprobe, tp);
566 if (strcmp(trace_kprobe_symbol(orig),
567 trace_kprobe_symbol(comp)) ||
568 trace_kprobe_offset(orig) != trace_kprobe_offset(comp))
572 * trace_probe_compare_arg_type() ensured that nr_args and
573 * each argument name and type are same. Let's compare comm.
575 for (i = 0; i < orig->tp.nr_args; i++) {
576 if (strcmp(orig->tp.args[i].comm,
577 comp->tp.args[i].comm))
581 if (i == orig->tp.nr_args)
588 static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to)
592 ret = trace_probe_compare_arg_type(&tk->tp, &to->tp);
594 /* Note that argument starts index = 2 */
595 trace_probe_log_set_index(ret + 1);
596 trace_probe_log_err(0, DIFF_ARG_TYPE);
599 if (trace_kprobe_has_same_kprobe(to, tk)) {
600 trace_probe_log_set_index(0);
601 trace_probe_log_err(0, SAME_PROBE);
605 /* Append to existing event */
606 ret = trace_probe_append(&tk->tp, &to->tp);
610 /* Register k*probe */
611 ret = __register_trace_kprobe(tk);
612 if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
613 pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
618 trace_probe_unlink(&tk->tp);
620 dyn_event_add(&tk->devent);
625 /* Register a trace_probe and probe_event */
626 static int register_trace_kprobe(struct trace_kprobe *tk)
628 struct trace_kprobe *old_tk;
631 mutex_lock(&event_mutex);
633 old_tk = find_trace_kprobe(trace_probe_name(&tk->tp),
634 trace_probe_group_name(&tk->tp));
636 if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) {
637 trace_probe_log_set_index(0);
638 trace_probe_log_err(0, DIFF_PROBE_TYPE);
641 ret = append_trace_kprobe(tk, old_tk);
646 /* Register new event */
647 ret = register_kprobe_event(tk);
649 pr_warn("Failed to register probe event(%d)\n", ret);
653 /* Register k*probe */
654 ret = __register_trace_kprobe(tk);
655 if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
656 pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
661 unregister_kprobe_event(tk);
663 dyn_event_add(&tk->devent);
666 mutex_unlock(&event_mutex);
670 /* Module notifier call back, checking event on the module */
671 static int trace_kprobe_module_callback(struct notifier_block *nb,
672 unsigned long val, void *data)
674 struct module *mod = data;
675 struct dyn_event *pos;
676 struct trace_kprobe *tk;
679 if (val != MODULE_STATE_COMING)
682 /* Update probes on coming module */
683 mutex_lock(&event_mutex);
684 for_each_trace_kprobe(tk, pos) {
685 if (trace_kprobe_within_module(tk, mod)) {
686 /* Don't need to check busy - this should have gone. */
687 __unregister_trace_kprobe(tk);
688 ret = __register_trace_kprobe(tk);
690 pr_warn("Failed to re-register probe %s on %s: %d\n",
691 trace_probe_name(&tk->tp),
695 mutex_unlock(&event_mutex);
700 static struct notifier_block trace_kprobe_module_nb = {
701 .notifier_call = trace_kprobe_module_callback,
702 .priority = 1 /* Invoked after kprobe module callback */
705 /* Convert certain expected symbols into '_' when generating event names */
706 static inline void sanitize_event_name(char *name)
708 while (*name++ != '\0')
709 if (*name == ':' || *name == '.')
713 static int trace_kprobe_create(int argc, const char *argv[])
718 * p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
720 * r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
722 * $retval : fetch return value
723 * $stack : fetch stack address
724 * $stackN : fetch Nth of stack (N:0-)
725 * $comm : fetch current task comm
726 * @ADDR : fetch memory at ADDR (ADDR should be in kernel)
727 * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
728 * %REG : fetch register REG
729 * Dereferencing memory fetch:
730 * +|-offs(ARG) : fetch memory at ARG +|- offs address.
731 * Alias name of args:
732 * NAME=FETCHARG : set NAME as alias of FETCHARG.
734 * FETCHARG:TYPE : use TYPE instead of unsigned long.
736 struct trace_kprobe *tk = NULL;
738 bool is_return = false;
739 char *symbol = NULL, *tmp = NULL;
740 const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
744 char buf[MAX_EVENT_NAME_LEN];
745 unsigned int flags = TPARG_FL_KERNEL;
747 switch (argv[0][0]) {
750 flags |= TPARG_FL_RETURN;
760 trace_probe_log_init("trace_kprobe", argc, argv);
762 event = strchr(&argv[0][1], ':');
766 if (isdigit(argv[0][1])) {
768 trace_probe_log_err(1, MAXACT_NO_KPROBE);
772 len = event - &argv[0][1] - 1;
774 len = strlen(&argv[0][1]);
775 if (len > MAX_EVENT_NAME_LEN - 1) {
776 trace_probe_log_err(1, BAD_MAXACT);
779 memcpy(buf, &argv[0][1], len);
781 ret = kstrtouint(buf, 0, &maxactive);
782 if (ret || !maxactive) {
783 trace_probe_log_err(1, BAD_MAXACT);
786 /* kretprobes instances are iterated over via a list. The
787 * maximum should stay reasonable.
789 if (maxactive > KRETPROBE_MAXACTIVE_MAX) {
790 trace_probe_log_err(1, MAXACT_TOO_BIG);
795 /* try to parse an address. if that fails, try to read the
796 * input as a symbol. */
797 if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) {
798 trace_probe_log_set_index(1);
799 /* Check whether uprobe event specified */
800 if (strchr(argv[1], '/') && strchr(argv[1], ':')) {
804 /* a symbol specified */
805 symbol = kstrdup(argv[1], GFP_KERNEL);
808 /* TODO: support .init module functions */
809 ret = traceprobe_split_symbol_offset(symbol, &offset);
810 if (ret || offset < 0 || offset > UINT_MAX) {
811 trace_probe_log_err(0, BAD_PROBE_ADDR);
814 if (kprobe_on_func_entry(NULL, symbol, offset))
815 flags |= TPARG_FL_FENTRY;
816 if (offset && is_return && !(flags & TPARG_FL_FENTRY)) {
817 trace_probe_log_err(0, BAD_RETPROBE);
822 trace_probe_log_set_index(0);
824 ret = traceprobe_parse_event_name(&event, &group, buf,
829 /* Make a new event name */
831 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
832 is_return ? 'r' : 'p', symbol, offset);
834 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
835 is_return ? 'r' : 'p', addr);
836 sanitize_event_name(buf);
841 tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,
842 argc - 2, is_return);
845 /* This must return -ENOMEM, else there is a bug */
846 WARN_ON_ONCE(ret != -ENOMEM);
847 goto out; /* We know tk is not allocated */
849 argc -= 2; argv += 2;
851 /* parse arguments */
852 for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
853 tmp = kstrdup(argv[i], GFP_KERNEL);
859 trace_probe_log_set_index(i + 2);
860 ret = traceprobe_parse_probe_arg(&tk->tp, i, tmp, flags);
863 goto error; /* This can be -ENOMEM */
866 ret = traceprobe_set_print_fmt(&tk->tp, is_return);
870 ret = register_trace_kprobe(tk);
872 trace_probe_log_set_index(1);
874 trace_probe_log_err(0, BAD_INSN_BNDRY);
875 else if (ret == -ENOENT)
876 trace_probe_log_err(0, BAD_PROBE_ADDR);
877 else if (ret != -ENOMEM && ret != -EEXIST)
878 trace_probe_log_err(0, FAIL_REG_PROBE);
883 trace_probe_log_clear();
890 free_trace_kprobe(tk);
894 static int create_or_delete_trace_kprobe(int argc, char **argv)
898 if (argv[0][0] == '-')
899 return dyn_event_release(argc, argv, &trace_kprobe_ops);
901 ret = trace_kprobe_create(argc, (const char **)argv);
902 return ret == -ECANCELED ? -EINVAL : ret;
905 static int trace_kprobe_release(struct dyn_event *ev)
907 struct trace_kprobe *tk = to_trace_kprobe(ev);
908 int ret = unregister_trace_kprobe(tk);
911 free_trace_kprobe(tk);
915 static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev)
917 struct trace_kprobe *tk = to_trace_kprobe(ev);
920 seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p');
921 seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp),
922 trace_probe_name(&tk->tp));
925 seq_printf(m, " 0x%p", tk->rp.kp.addr);
926 else if (tk->rp.kp.offset)
927 seq_printf(m, " %s+%u", trace_kprobe_symbol(tk),
930 seq_printf(m, " %s", trace_kprobe_symbol(tk));
932 for (i = 0; i < tk->tp.nr_args; i++)
933 seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm);
939 static int probes_seq_show(struct seq_file *m, void *v)
941 struct dyn_event *ev = v;
943 if (!is_trace_kprobe(ev))
946 return trace_kprobe_show(m, ev);
949 static const struct seq_operations probes_seq_op = {
950 .start = dyn_event_seq_start,
951 .next = dyn_event_seq_next,
952 .stop = dyn_event_seq_stop,
953 .show = probes_seq_show
956 static int probes_open(struct inode *inode, struct file *file)
960 ret = security_locked_down(LOCKDOWN_TRACEFS);
964 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
965 ret = dyn_events_release_all(&trace_kprobe_ops);
970 return seq_open(file, &probes_seq_op);
973 static ssize_t probes_write(struct file *file, const char __user *buffer,
974 size_t count, loff_t *ppos)
976 return trace_parse_run_command(file, buffer, count, ppos,
977 create_or_delete_trace_kprobe);
980 static const struct file_operations kprobe_events_ops = {
981 .owner = THIS_MODULE,
985 .release = seq_release,
986 .write = probes_write,
989 /* Probes profiling interfaces */
990 static int probes_profile_seq_show(struct seq_file *m, void *v)
992 struct dyn_event *ev = v;
993 struct trace_kprobe *tk;
995 if (!is_trace_kprobe(ev))
998 tk = to_trace_kprobe(ev);
999 seq_printf(m, " %-44s %15lu %15lu\n",
1000 trace_probe_name(&tk->tp),
1001 trace_kprobe_nhit(tk),
1007 static const struct seq_operations profile_seq_op = {
1008 .start = dyn_event_seq_start,
1009 .next = dyn_event_seq_next,
1010 .stop = dyn_event_seq_stop,
1011 .show = probes_profile_seq_show
1014 static int profile_open(struct inode *inode, struct file *file)
1018 ret = security_locked_down(LOCKDOWN_TRACEFS);
1022 return seq_open(file, &profile_seq_op);
1025 static const struct file_operations kprobe_profile_ops = {
1026 .owner = THIS_MODULE,
1027 .open = profile_open,
1029 .llseek = seq_lseek,
1030 .release = seq_release,
1033 /* Kprobe specific fetch functions */
1035 /* Return the length of string -- including null terminal byte */
1036 static nokprobe_inline int
1037 fetch_store_strlen(unsigned long addr)
1043 ret = probe_kernel_read(&c, (u8 *)addr + len, 1);
1045 } while (c && ret == 0 && len < MAX_STRING_SIZE);
1047 return (ret < 0) ? ret : len;
1050 /* Return the length of string -- including null terminal byte */
1051 static nokprobe_inline int
1052 fetch_store_strlen_user(unsigned long addr)
1054 const void __user *uaddr = (__force const void __user *)addr;
1056 return strnlen_unsafe_user(uaddr, MAX_STRING_SIZE);
1060 * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
1061 * length and relative data location.
1063 static nokprobe_inline int
1064 fetch_store_string(unsigned long addr, void *dest, void *base)
1066 int maxlen = get_loc_len(*(u32 *)dest);
1070 if (unlikely(!maxlen))
1073 __dest = get_loc_data(dest, base);
1076 * Try to get string again, since the string can be changed while
1079 ret = strncpy_from_unsafe(__dest, (void *)addr, maxlen);
1081 *(u32 *)dest = make_data_loc(ret, __dest - base);
1087 * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
1088 * with max length and relative data location.
1090 static nokprobe_inline int
1091 fetch_store_string_user(unsigned long addr, void *dest, void *base)
1093 const void __user *uaddr = (__force const void __user *)addr;
1094 int maxlen = get_loc_len(*(u32 *)dest);
1098 if (unlikely(!maxlen))
1101 __dest = get_loc_data(dest, base);
1103 ret = strncpy_from_unsafe_user(__dest, uaddr, maxlen);
1105 *(u32 *)dest = make_data_loc(ret, __dest - base);
1110 static nokprobe_inline int
1111 probe_mem_read(void *dest, void *src, size_t size)
1113 return probe_kernel_read(dest, src, size);
1116 static nokprobe_inline int
1117 probe_mem_read_user(void *dest, void *src, size_t size)
1119 const void __user *uaddr = (__force const void __user *)src;
1121 return probe_user_read(dest, uaddr, size);
1124 /* Note that we don't verify it, since the code does not come from user space */
1126 process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
1132 /* 1st stage: get value from context */
1135 val = regs_get_register(regs, code->param);
1137 case FETCH_OP_STACK:
1138 val = regs_get_kernel_stack_nth(regs, code->param);
1140 case FETCH_OP_STACKP:
1141 val = kernel_stack_pointer(regs);
1143 case FETCH_OP_RETVAL:
1144 val = regs_return_value(regs);
1147 val = code->immediate;
1150 val = (unsigned long)current->comm;
1153 val = (unsigned long)code->data;
1155 #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
1157 val = regs_get_kernel_argument(regs, code->param);
1160 case FETCH_NOP_SYMBOL: /* Ignore a place holder */
1168 return process_fetch_insn_bottom(code, val, dest, base);
1170 NOKPROBE_SYMBOL(process_fetch_insn)
1172 /* Kprobe handler */
1173 static nokprobe_inline void
1174 __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
1175 struct trace_event_file *trace_file)
1177 struct kprobe_trace_entry_head *entry;
1178 struct ring_buffer_event *event;
1179 struct ring_buffer *buffer;
1180 int size, dsize, pc;
1181 unsigned long irq_flags;
1182 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1184 WARN_ON(call != trace_file->event_call);
1186 if (trace_trigger_soft_disabled(trace_file))
1189 local_save_flags(irq_flags);
1190 pc = preempt_count();
1192 dsize = __get_data_size(&tk->tp, regs);
1193 size = sizeof(*entry) + tk->tp.size + dsize;
1195 event = trace_event_buffer_lock_reserve(&buffer, trace_file,
1197 size, irq_flags, pc);
1201 entry = ring_buffer_event_data(event);
1202 entry->ip = (unsigned long)tk->rp.kp.addr;
1203 store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
1205 event_trigger_unlock_commit_regs(trace_file, buffer, event,
1206 entry, irq_flags, pc, regs);
1210 kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs)
1212 struct event_file_link *link;
1214 trace_probe_for_each_link_rcu(link, &tk->tp)
1215 __kprobe_trace_func(tk, regs, link->file);
1217 NOKPROBE_SYMBOL(kprobe_trace_func);
1219 /* Kretprobe handler */
1220 static nokprobe_inline void
1221 __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
1222 struct pt_regs *regs,
1223 struct trace_event_file *trace_file)
1225 struct kretprobe_trace_entry_head *entry;
1226 struct ring_buffer_event *event;
1227 struct ring_buffer *buffer;
1228 int size, pc, dsize;
1229 unsigned long irq_flags;
1230 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1232 WARN_ON(call != trace_file->event_call);
1234 if (trace_trigger_soft_disabled(trace_file))
1237 local_save_flags(irq_flags);
1238 pc = preempt_count();
1240 dsize = __get_data_size(&tk->tp, regs);
1241 size = sizeof(*entry) + tk->tp.size + dsize;
1243 event = trace_event_buffer_lock_reserve(&buffer, trace_file,
1245 size, irq_flags, pc);
1249 entry = ring_buffer_event_data(event);
1250 entry->func = (unsigned long)tk->rp.kp.addr;
1251 entry->ret_ip = (unsigned long)ri->ret_addr;
1252 store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
1254 event_trigger_unlock_commit_regs(trace_file, buffer, event,
1255 entry, irq_flags, pc, regs);
1259 kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
1260 struct pt_regs *regs)
1262 struct event_file_link *link;
1264 trace_probe_for_each_link_rcu(link, &tk->tp)
1265 __kretprobe_trace_func(tk, ri, regs, link->file);
1267 NOKPROBE_SYMBOL(kretprobe_trace_func);
1269 /* Event entry printers */
1270 static enum print_line_t
1271 print_kprobe_event(struct trace_iterator *iter, int flags,
1272 struct trace_event *event)
1274 struct kprobe_trace_entry_head *field;
1275 struct trace_seq *s = &iter->seq;
1276 struct trace_probe *tp;
1278 field = (struct kprobe_trace_entry_head *)iter->ent;
1279 tp = trace_probe_primary_from_call(
1280 container_of(event, struct trace_event_call, event));
1281 if (WARN_ON_ONCE(!tp))
1284 trace_seq_printf(s, "%s: (", trace_probe_name(tp));
1286 if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
1289 trace_seq_putc(s, ')');
1291 if (print_probe_args(s, tp->args, tp->nr_args,
1292 (u8 *)&field[1], field) < 0)
1295 trace_seq_putc(s, '\n');
1297 return trace_handle_return(s);
1300 static enum print_line_t
1301 print_kretprobe_event(struct trace_iterator *iter, int flags,
1302 struct trace_event *event)
1304 struct kretprobe_trace_entry_head *field;
1305 struct trace_seq *s = &iter->seq;
1306 struct trace_probe *tp;
1308 field = (struct kretprobe_trace_entry_head *)iter->ent;
1309 tp = trace_probe_primary_from_call(
1310 container_of(event, struct trace_event_call, event));
1311 if (WARN_ON_ONCE(!tp))
1314 trace_seq_printf(s, "%s: (", trace_probe_name(tp));
1316 if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
1319 trace_seq_puts(s, " <- ");
1321 if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
1324 trace_seq_putc(s, ')');
1326 if (print_probe_args(s, tp->args, tp->nr_args,
1327 (u8 *)&field[1], field) < 0)
1330 trace_seq_putc(s, '\n');
1333 return trace_handle_return(s);
1337 static int kprobe_event_define_fields(struct trace_event_call *event_call)
1340 struct kprobe_trace_entry_head field;
1341 struct trace_probe *tp;
1343 tp = trace_probe_primary_from_call(event_call);
1344 if (WARN_ON_ONCE(!tp))
1347 DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
1349 return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
1352 static int kretprobe_event_define_fields(struct trace_event_call *event_call)
1355 struct kretprobe_trace_entry_head field;
1356 struct trace_probe *tp;
1358 tp = trace_probe_primary_from_call(event_call);
1359 if (WARN_ON_ONCE(!tp))
1362 DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
1363 DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
1365 return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
1368 #ifdef CONFIG_PERF_EVENTS
1370 /* Kprobe profile handler */
1372 kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
1374 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1375 struct kprobe_trace_entry_head *entry;
1376 struct hlist_head *head;
1377 int size, __size, dsize;
1380 if (bpf_prog_array_valid(call)) {
1381 unsigned long orig_ip = instruction_pointer(regs);
1384 ret = trace_call_bpf(call, regs);
1387 * We need to check and see if we modified the pc of the
1388 * pt_regs, and if so return 1 so that we don't do the
1391 if (orig_ip != instruction_pointer(regs))
1397 head = this_cpu_ptr(call->perf_events);
1398 if (hlist_empty(head))
1401 dsize = __get_data_size(&tk->tp, regs);
1402 __size = sizeof(*entry) + tk->tp.size + dsize;
1403 size = ALIGN(__size + sizeof(u32), sizeof(u64));
1404 size -= sizeof(u32);
1406 entry = perf_trace_buf_alloc(size, NULL, &rctx);
1410 entry->ip = (unsigned long)tk->rp.kp.addr;
1411 memset(&entry[1], 0, dsize);
1412 store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
1413 perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
1417 NOKPROBE_SYMBOL(kprobe_perf_func);
1419 /* Kretprobe profile handler */
1421 kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
1422 struct pt_regs *regs)
1424 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1425 struct kretprobe_trace_entry_head *entry;
1426 struct hlist_head *head;
1427 int size, __size, dsize;
1430 if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
1433 head = this_cpu_ptr(call->perf_events);
1434 if (hlist_empty(head))
1437 dsize = __get_data_size(&tk->tp, regs);
1438 __size = sizeof(*entry) + tk->tp.size + dsize;
1439 size = ALIGN(__size + sizeof(u32), sizeof(u64));
1440 size -= sizeof(u32);
1442 entry = perf_trace_buf_alloc(size, NULL, &rctx);
1446 entry->func = (unsigned long)tk->rp.kp.addr;
1447 entry->ret_ip = (unsigned long)ri->ret_addr;
1448 store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
1449 perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
1452 NOKPROBE_SYMBOL(kretprobe_perf_func);
1454 int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type,
1455 const char **symbol, u64 *probe_offset,
1456 u64 *probe_addr, bool perf_type_tracepoint)
1458 const char *pevent = trace_event_name(event->tp_event);
1459 const char *group = event->tp_event->class->system;
1460 struct trace_kprobe *tk;
1462 if (perf_type_tracepoint)
1463 tk = find_trace_kprobe(pevent, group);
1465 tk = event->tp_event->data;
1469 *fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE
1470 : BPF_FD_TYPE_KPROBE;
1472 *symbol = tk->symbol;
1473 *probe_offset = tk->rp.kp.offset;
1478 *probe_addr = (unsigned long)tk->rp.kp.addr;
1482 #endif /* CONFIG_PERF_EVENTS */
1485 * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex.
1487 * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe
1488 * lockless, but we can't race with this __init function.
1490 static int kprobe_register(struct trace_event_call *event,
1491 enum trace_reg type, void *data)
1493 struct trace_event_file *file = data;
1496 case TRACE_REG_REGISTER:
1497 return enable_trace_kprobe(event, file);
1498 case TRACE_REG_UNREGISTER:
1499 return disable_trace_kprobe(event, file);
1501 #ifdef CONFIG_PERF_EVENTS
1502 case TRACE_REG_PERF_REGISTER:
1503 return enable_trace_kprobe(event, NULL);
1504 case TRACE_REG_PERF_UNREGISTER:
1505 return disable_trace_kprobe(event, NULL);
1506 case TRACE_REG_PERF_OPEN:
1507 case TRACE_REG_PERF_CLOSE:
1508 case TRACE_REG_PERF_ADD:
1509 case TRACE_REG_PERF_DEL:
1516 static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
1518 struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp);
1521 raw_cpu_inc(*tk->nhit);
1523 if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
1524 kprobe_trace_func(tk, regs);
1525 #ifdef CONFIG_PERF_EVENTS
1526 if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
1527 ret = kprobe_perf_func(tk, regs);
1531 NOKPROBE_SYMBOL(kprobe_dispatcher);
1534 kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
1536 struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp);
1538 raw_cpu_inc(*tk->nhit);
1540 if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
1541 kretprobe_trace_func(tk, ri, regs);
1542 #ifdef CONFIG_PERF_EVENTS
1543 if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
1544 kretprobe_perf_func(tk, ri, regs);
1546 return 0; /* We don't tweek kernel, so just return 0 */
1548 NOKPROBE_SYMBOL(kretprobe_dispatcher);
1550 static struct trace_event_functions kretprobe_funcs = {
1551 .trace = print_kretprobe_event
1554 static struct trace_event_functions kprobe_funcs = {
1555 .trace = print_kprobe_event
1558 static inline void init_trace_event_call(struct trace_kprobe *tk)
1560 struct trace_event_call *call = trace_probe_event_call(&tk->tp);
1562 if (trace_kprobe_is_return(tk)) {
1563 call->event.funcs = &kretprobe_funcs;
1564 call->class->define_fields = kretprobe_event_define_fields;
1566 call->event.funcs = &kprobe_funcs;
1567 call->class->define_fields = kprobe_event_define_fields;
1570 call->flags = TRACE_EVENT_FL_KPROBE;
1571 call->class->reg = kprobe_register;
1574 static int register_kprobe_event(struct trace_kprobe *tk)
1576 init_trace_event_call(tk);
1578 return trace_probe_register_event_call(&tk->tp);
1581 static int unregister_kprobe_event(struct trace_kprobe *tk)
1583 return trace_probe_unregister_event_call(&tk->tp);
1586 #ifdef CONFIG_PERF_EVENTS
1587 /* create a trace_kprobe, but don't add it to global lists */
1588 struct trace_event_call *
1589 create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
1592 struct trace_kprobe *tk;
1597 * local trace_kprobes are not added to dyn_event, so they are never
1598 * searched in find_trace_kprobe(). Therefore, there is no concern of
1599 * duplicated name here.
1601 event = func ? func : "DUMMY_EVENT";
1603 tk = alloc_trace_kprobe(KPROBE_EVENT_SYSTEM, event, (void *)addr, func,
1604 offs, 0 /* maxactive */, 0 /* nargs */,
1608 pr_info("Failed to allocate trace_probe.(%d)\n",
1610 return ERR_CAST(tk);
1613 init_trace_event_call(tk);
1615 if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) {
1620 ret = __register_trace_kprobe(tk);
1624 return trace_probe_event_call(&tk->tp);
1626 free_trace_kprobe(tk);
1627 return ERR_PTR(ret);
1630 void destroy_local_trace_kprobe(struct trace_event_call *event_call)
1632 struct trace_kprobe *tk;
1634 tk = trace_kprobe_primary_from_call(event_call);
1638 if (trace_probe_is_enabled(&tk->tp)) {
1643 __unregister_trace_kprobe(tk);
1645 free_trace_kprobe(tk);
1647 #endif /* CONFIG_PERF_EVENTS */
1649 static __init void enable_boot_kprobe_events(void)
1651 struct trace_array *tr = top_trace_array();
1652 struct trace_event_file *file;
1653 struct trace_kprobe *tk;
1654 struct dyn_event *pos;
1656 mutex_lock(&event_mutex);
1657 for_each_trace_kprobe(tk, pos) {
1658 list_for_each_entry(file, &tr->events, list)
1659 if (file->event_call == trace_probe_event_call(&tk->tp))
1660 trace_event_enable_disable(file, 1, 0);
1662 mutex_unlock(&event_mutex);
1665 static __init void setup_boot_kprobe_events(void)
1667 char *p, *cmd = kprobe_boot_events_buf;
1670 strreplace(kprobe_boot_events_buf, ',', ' ');
1672 while (cmd && *cmd != '\0') {
1673 p = strchr(cmd, ';');
1677 ret = trace_run_command(cmd, create_or_delete_trace_kprobe);
1679 pr_warn("Failed to add event(%d): %s\n", ret, cmd);
1681 kprobe_boot_events_enabled = true;
1686 enable_boot_kprobe_events();
1689 /* Make a tracefs interface for controlling probe points */
1690 static __init int init_kprobe_trace(void)
1692 struct dentry *d_tracer;
1693 struct dentry *entry;
1696 ret = dyn_event_register(&trace_kprobe_ops);
1700 if (register_module_notifier(&trace_kprobe_module_nb))
1703 d_tracer = tracing_init_dentry();
1704 if (IS_ERR(d_tracer))
1707 entry = tracefs_create_file("kprobe_events", 0644, d_tracer,
1708 NULL, &kprobe_events_ops);
1710 /* Event list interface */
1712 pr_warn("Could not create tracefs 'kprobe_events' entry\n");
1714 /* Profile interface */
1715 entry = tracefs_create_file("kprobe_profile", 0444, d_tracer,
1716 NULL, &kprobe_profile_ops);
1719 pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
1721 setup_boot_kprobe_events();
1725 fs_initcall(init_kprobe_trace);
1728 #ifdef CONFIG_FTRACE_STARTUP_TEST
1729 static __init struct trace_event_file *
1730 find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
1732 struct trace_event_file *file;
1734 list_for_each_entry(file, &tr->events, list)
1735 if (file->event_call == trace_probe_event_call(&tk->tp))
1742 * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this
1743 * stage, we can do this lockless.
1745 static __init int kprobe_trace_self_tests_init(void)
1748 int (*target)(int, int, int, int, int, int);
1749 struct trace_kprobe *tk;
1750 struct trace_event_file *file;
1752 if (tracing_is_disabled())
1755 if (kprobe_boot_events_enabled) {
1756 pr_info("Skipping kprobe tests due to kprobe_event on cmdline\n");
1760 target = kprobe_trace_selftest_target;
1762 pr_info("Testing kprobe tracing: ");
1764 ret = trace_run_command("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)",
1765 create_or_delete_trace_kprobe);
1766 if (WARN_ON_ONCE(ret)) {
1767 pr_warn("error on probing function entry.\n");
1770 /* Enable trace point */
1771 tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
1772 if (WARN_ON_ONCE(tk == NULL)) {
1773 pr_warn("error on getting new probe.\n");
1776 file = find_trace_probe_file(tk, top_trace_array());
1777 if (WARN_ON_ONCE(file == NULL)) {
1778 pr_warn("error on getting probe file.\n");
1781 enable_trace_kprobe(
1782 trace_probe_event_call(&tk->tp), file);
1786 ret = trace_run_command("r:testprobe2 kprobe_trace_selftest_target $retval",
1787 create_or_delete_trace_kprobe);
1788 if (WARN_ON_ONCE(ret)) {
1789 pr_warn("error on probing function return.\n");
1792 /* Enable trace point */
1793 tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
1794 if (WARN_ON_ONCE(tk == NULL)) {
1795 pr_warn("error on getting 2nd new probe.\n");
1798 file = find_trace_probe_file(tk, top_trace_array());
1799 if (WARN_ON_ONCE(file == NULL)) {
1800 pr_warn("error on getting probe file.\n");
1803 enable_trace_kprobe(
1804 trace_probe_event_call(&tk->tp), file);
1811 ret = target(1, 2, 3, 4, 5, 6);
1814 * Not expecting an error here, the check is only to prevent the
1815 * optimizer from removing the call to target() as otherwise there
1816 * are no side-effects and the call is never performed.
1821 /* Disable trace points before removing it */
1822 tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
1823 if (WARN_ON_ONCE(tk == NULL)) {
1824 pr_warn("error on getting test probe.\n");
1827 if (trace_kprobe_nhit(tk) != 1) {
1828 pr_warn("incorrect number of testprobe hits\n");
1832 file = find_trace_probe_file(tk, top_trace_array());
1833 if (WARN_ON_ONCE(file == NULL)) {
1834 pr_warn("error on getting probe file.\n");
1837 disable_trace_kprobe(
1838 trace_probe_event_call(&tk->tp), file);
1841 tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
1842 if (WARN_ON_ONCE(tk == NULL)) {
1843 pr_warn("error on getting 2nd test probe.\n");
1846 if (trace_kprobe_nhit(tk) != 1) {
1847 pr_warn("incorrect number of testprobe2 hits\n");
1851 file = find_trace_probe_file(tk, top_trace_array());
1852 if (WARN_ON_ONCE(file == NULL)) {
1853 pr_warn("error on getting probe file.\n");
1856 disable_trace_kprobe(
1857 trace_probe_event_call(&tk->tp), file);
1860 ret = trace_run_command("-:testprobe", create_or_delete_trace_kprobe);
1861 if (WARN_ON_ONCE(ret)) {
1862 pr_warn("error on deleting a probe.\n");
1866 ret = trace_run_command("-:testprobe2", create_or_delete_trace_kprobe);
1867 if (WARN_ON_ONCE(ret)) {
1868 pr_warn("error on deleting a probe.\n");
1873 ret = dyn_events_release_all(&trace_kprobe_ops);
1874 if (WARN_ON_ONCE(ret)) {
1875 pr_warn("error on cleaning up probes.\n");
1879 * Wait for the optimizer work to finish. Otherwise it might fiddle
1880 * with probes in already freed __init text.
1882 wait_for_kprobe_optimizer();
1884 pr_cont("NG: Some tests are failed. Please check them.\n");
1890 late_initcall(kprobe_trace_self_tests_init);