Commit 57d4e317 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Steven Rostedt (VMware)
Browse files

kprobes: Add assertions for required lock 

Add assertions for required locks instead of comment it
so that the lockdep can inspect locks automatically.

Link: https://lkml.kernel.org/r/163163039572.489837.18011973177537476885.stgit@devnote2



Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent dfc05b55

kernel/kprobes.c

+12 −7
Original line number Diff line number Diff line
@@ -959,11 +959,13 @@ int proc_kprobes_optimization_handler(struct ctl_table *table, int write, 
}

#endif /* CONFIG_SYSCTL */



/* Put a breakpoint for a probe. Must be called with 'text_mutex' locked. */

/* Put a breakpoint for a probe. */

static void __arm_kprobe(struct kprobe *p)

{

	struct kprobe *_p;



	lockdep_assert_held(&text_mutex);



	/* Find the overlapping optimized kprobes. */

	_p = get_optimized_kprobe((unsigned long)p->addr);

	if (unlikely(_p))
@@ -974,11 +976,13 @@ static void __arm_kprobe(struct kprobe *p) 
	optimize_kprobe(p);	/* Try to optimize (add kprobe to a list) */

}



/* Remove the breakpoint of a probe. Must be called with 'text_mutex' locked. */

/* Remove the breakpoint of a probe. */

static void __disarm_kprobe(struct kprobe *p, bool reopt)

{

	struct kprobe *_p;



	lockdep_assert_held(&text_mutex);



	/* Try to unoptimize */

	unoptimize_kprobe(p, kprobes_all_disarmed);
@@ -1047,12 +1051,13 @@ static struct ftrace_ops kprobe_ipmodify_ops __read_mostly = { 
static int kprobe_ipmodify_enabled;

static int kprobe_ftrace_enabled;



/* Caller must lock 'kprobe_mutex' */

static int __arm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops,

			       int *cnt)

{

	int ret = 0;



	lockdep_assert_held(&kprobe_mutex);



	ret = ftrace_set_filter_ip(ops, (unsigned long)p->addr, 0, 0);

	if (WARN_ONCE(ret < 0, "Failed to arm kprobe-ftrace at %pS (error %d)\n", p->addr, ret))

		return ret;
@@ -1084,12 +1089,13 @@ static int arm_kprobe_ftrace(struct kprobe *p) 
		ipmodify ? &kprobe_ipmodify_enabled : &kprobe_ftrace_enabled);

}



/* Caller must lock 'kprobe_mutex'. */

static int __disarm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops,

				  int *cnt)

{

	int ret = 0;



	lockdep_assert_held(&kprobe_mutex);



	if (*cnt == 1) {

		ret = unregister_ftrace_function(ops);

		if (WARN(ret < 0, "Failed to unregister kprobe-ftrace (error %d)\n", ret))
@@ -1133,7 +1139,6 @@ static int prepare_kprobe(struct kprobe *p) 
	return arch_prepare_kprobe(p);

}



/* Arm a kprobe with 'text_mutex'. */

static int arm_kprobe(struct kprobe *kp)

{

	if (unlikely(kprobe_ftrace(kp)))
@@ -1148,7 +1153,6 @@ static int arm_kprobe(struct kprobe *kp) 
	return 0;

}



/* Disarm a kprobe with 'text_mutex'. */

static int disarm_kprobe(struct kprobe *kp, bool reopt)

{

	if (unlikely(kprobe_ftrace(kp)))
@@ -1691,12 +1695,13 @@ static int aggr_kprobe_disabled(struct kprobe *ap) 
	return 1;

}



/* Disable one kprobe: Make sure called under 'kprobe_mutex' is locked. */

static struct kprobe *__disable_kprobe(struct kprobe *p)

{

	struct kprobe *orig_p;

	int ret;



	lockdep_assert_held(&kprobe_mutex);



	/* Get an original kprobe for return */

	orig_p = __get_valid_kprobe(p);

	if (unlikely(orig_p == NULL))