From: Andrea Righi <righi.and...@gmail.com>

[ Upstream commit 02106f883cd745523f7766d90a739f983f19e650 ]

Since kprobe breakpoing handler is using bsearch(), probing on this
routine can cause recursive breakpoint problem.

int3
 ->do_int3()
   ->ftrace_int3_handler()
     ->ftrace_location()
       ->ftrace_location_range()
         ->bsearch() -> int3

Prohibit probing on bsearch().

Signed-off-by: Andrea Righi <righi.and...@gmail.com>
Acked-by: Masami Hiramatsu <mhira...@kernel.org>
Cc: Alexander Shishkin <alexander.shish...@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Cc: Jiri Olsa <jo...@redhat.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Steven Rostedt <rost...@goodmis.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Link: 
http://lkml.kernel.org/r/154998813406.31052.8791425358974650922.stgit@devbox
Signed-off-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 lib/bsearch.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/bsearch.c b/lib/bsearch.c
index 18b445b010c3..82512fe7b33c 100644
--- a/lib/bsearch.c
+++ b/lib/bsearch.c
@@ -11,6 +11,7 @@
 
 #include <linux/export.h>
 #include <linux/bsearch.h>
+#include <linux/kprobes.h>
 
 /*
  * bsearch - binary search an array of elements
@@ -53,3 +54,4 @@ void *bsearch(const void *key, const void *base, size_t num, 
size_t size,
        return NULL;
 }
 EXPORT_SYMBOL(bsearch);
+NOKPROBE_SYMBOL(bsearch);
-- 
2.19.1

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