Commit bf7a87f1 authored by Jiri Olsa's avatar Jiri Olsa Committed by Alexei Starovoitov
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kprobes: Add new KPROBE_FLAG_ON_FUNC_ENTRY kprobe flag 



Adding KPROBE_FLAG_ON_FUNC_ENTRY kprobe flag to indicate that
attach address is on function entry. This is used in following
changes in get_func_ip helper to return correct function address.

Acked-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20220926153340.1621984-2-jolsa@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent bec21719

include/linux/kprobes.h

+1 −0
Original line number Diff line number Diff line
@@ -103,6 +103,7 @@ struct kprobe { 
				   * this flag is only for optimized_kprobe.

				   */

#define KPROBE_FLAG_FTRACE	8 /* probe is using ftrace */

#define KPROBE_FLAG_ON_FUNC_ENTRY	16 /* probe is on the function entry */



/* Has this kprobe gone ? */

static inline bool kprobe_gone(struct kprobe *p)

kernel/kprobes.c

+5 −1
Original line number Diff line number Diff line
@@ -1606,9 +1606,10 @@ int register_kprobe(struct kprobe *p) 
	struct kprobe *old_p;

	struct module *probed_mod;

	kprobe_opcode_t *addr;

	bool on_func_entry;



	/* Adjust probe address from symbol */

	addr = kprobe_addr(p);

	addr = _kprobe_addr(p->addr, p->symbol_name, p->offset, &on_func_entry);

	if (IS_ERR(addr))

		return PTR_ERR(addr);

	p->addr = addr;
@@ -1628,6 +1629,9 @@ int register_kprobe(struct kprobe *p) 


	mutex_lock(&kprobe_mutex);



	if (on_func_entry)

		p->flags |= KPROBE_FLAG_ON_FUNC_ENTRY;



	old_p = get_kprobe(p->addr);

	if (old_p) {

		/* Since this may unoptimize 'old_p', locking 'text_mutex'. */