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	 02106f883c
			
		
	
	
		02106f883c
		
	
	
	
	
		
			
			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.andrea@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998813406.31052.8791425358974650922.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
	
			
		
			
				
	
	
		
			57 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			57 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * A generic implementation of binary search for the Linux kernel
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|  *
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|  * Copyright (C) 2008-2009 Ksplice, Inc.
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|  * Author: Tim Abbott <tabbott@ksplice.com>
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License as
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|  * published by the Free Software Foundation; version 2.
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|  */
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| 
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| #include <linux/export.h>
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| #include <linux/bsearch.h>
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| #include <linux/kprobes.h>
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| 
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| /*
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|  * bsearch - binary search an array of elements
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|  * @key: pointer to item being searched for
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|  * @base: pointer to first element to search
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|  * @num: number of elements
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|  * @size: size of each element
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|  * @cmp: pointer to comparison function
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|  *
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|  * This function does a binary search on the given array.  The
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|  * contents of the array should already be in ascending sorted order
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|  * under the provided comparison function.
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|  *
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|  * Note that the key need not have the same type as the elements in
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|  * the array, e.g. key could be a string and the comparison function
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|  * could compare the string with the struct's name field.  However, if
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|  * the key and elements in the array are of the same type, you can use
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|  * the same comparison function for both sort() and bsearch().
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|  */
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| void *bsearch(const void *key, const void *base, size_t num, size_t size,
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| 	      int (*cmp)(const void *key, const void *elt))
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| {
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| 	const char *pivot;
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| 	int result;
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| 
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| 	while (num > 0) {
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| 		pivot = base + (num >> 1) * size;
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| 		result = cmp(key, pivot);
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| 
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| 		if (result == 0)
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| 			return (void *)pivot;
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| 
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| 		if (result > 0) {
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| 			base = pivot + size;
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| 			num--;
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| 		}
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| 		num >>= 1;
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| 	}
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| 
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| 	return NULL;
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| }
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| EXPORT_SYMBOL(bsearch);
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| NOKPROBE_SYMBOL(bsearch);
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