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-rw-r--r--Documentation/kprobes.txt38
1 files changed, 32 insertions, 6 deletions
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt
index 48b3de90eb1e..1e7a769a10f9 100644
--- a/Documentation/kprobes.txt
+++ b/Documentation/kprobes.txt
@@ -212,7 +212,9 @@ hit, Kprobes calls kp->pre_handler. After the probed instruction
212is single-stepped, Kprobe calls kp->post_handler. If a fault 212is single-stepped, Kprobe calls kp->post_handler. If a fault
213occurs during execution of kp->pre_handler or kp->post_handler, 213occurs during execution of kp->pre_handler or kp->post_handler,
214or during single-stepping of the probed instruction, Kprobes calls 214or during single-stepping of the probed instruction, Kprobes calls
215kp->fault_handler. Any or all handlers can be NULL. 215kp->fault_handler. Any or all handlers can be NULL. If kp->flags
216is set KPROBE_FLAG_DISABLED, that kp will be registered but disabled,
217so, it's handlers aren't hit until calling enable_kprobe(kp).
216 218
217NOTE: 219NOTE:
2181. With the introduction of the "symbol_name" field to struct kprobe, 2201. With the introduction of the "symbol_name" field to struct kprobe,
@@ -363,6 +365,26 @@ probes) in the specified array, they clear the addr field of those
363incorrect probes. However, other probes in the array are 365incorrect probes. However, other probes in the array are
364unregistered correctly. 366unregistered correctly.
365 367
3684.7 disable_*probe
369
370#include <linux/kprobes.h>
371int disable_kprobe(struct kprobe *kp);
372int disable_kretprobe(struct kretprobe *rp);
373int disable_jprobe(struct jprobe *jp);
374
375Temporarily disables the specified *probe. You can enable it again by using
376enable_*probe(). You must specify the probe which has been registered.
377
3784.8 enable_*probe
379
380#include <linux/kprobes.h>
381int enable_kprobe(struct kprobe *kp);
382int enable_kretprobe(struct kretprobe *rp);
383int enable_jprobe(struct jprobe *jp);
384
385Enables *probe which has been disabled by disable_*probe(). You must specify
386the probe which has been registered.
387
3665. Kprobes Features and Limitations 3885. Kprobes Features and Limitations
367 389
368Kprobes allows multiple probes at the same address. Currently, 390Kprobes allows multiple probes at the same address. Currently,
@@ -500,10 +522,14 @@ the probe. If the probed function belongs to a module, the module name
500is also specified. Following columns show probe status. If the probe is on 522is also specified. Following columns show probe status. If the probe is on
501a virtual address that is no longer valid (module init sections, module 523a virtual address that is no longer valid (module init sections, module
502virtual addresses that correspond to modules that've been unloaded), 524virtual addresses that correspond to modules that've been unloaded),
503such probes are marked with [GONE]. 525such probes are marked with [GONE]. If the probe is temporarily disabled,
526such probes are marked with [DISABLED].
504 527
505/debug/kprobes/enabled: Turn kprobes ON/OFF 528/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly.
506 529
507Provides a knob to globally turn registered kprobes ON or OFF. By default, 530Provides a knob to globally and forcibly turn registered kprobes ON or OFF.
508all kprobes are enabled. By echoing "0" to this file, all registered probes 531By default, all kprobes are enabled. By echoing "0" to this file, all
509will be disarmed, till such time a "1" is echoed to this file. 532registered probes will be disarmed, till such time a "1" is echoed to this
533file. Note that this knob just disarms and arms all kprobes and doesn't
534change each probe's disabling state. This means that disabled kprobes (marked
535[DISABLED]) will be not enabled if you turn ON all kprobes by this knob.