commit fbc1963d2c1c4eb4651132a2c5c9d6111ada17d3
author Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Thu Apr 17 17:18:00 2014 +0900
committer Ingo Molnar <mingo@kernel.org> Thu Apr 24 10:03:02 2014 +0200
tree f1fe435182c467a7fe42ffdaca1da7ce7e9a85b5
parent 55479f64756fc508182a05e35e52f01395a50d4d

kprobes, ftrace: Allow probing on some functions

There is no need to prohibit probing on the functions
used for preparation and uprobe only fetch functions.
Those are safely probed because those are not invoked
from kprobe's breakpoint/fault/debug handlers. So there
is no chance to cause recursive exceptions.

Following functions are now removed from the kprobes blacklist:

	update_bitfield_fetch_param
	free_bitfield_fetch_param
	kprobe_register
	FETCH_FUNC_NAME(stack, type) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, type) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, string) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, string_size) in trace_uprobe.c
	FETCH_FUNC_NAME(file_offset, type) in trace_uprobe.c

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140417081800.26341.56504.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/trace/trace_uprobe.c

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index c082a74..991e3b7 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -108,8 +108,8 @@
  * Uprobes-specific fetch functions
  */
 #define DEFINE_FETCH_stack(type)					\
-static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
-					  void *offset, void *dest)	\
+static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,		\
+					 void *offset, void *dest)	\
 {									\
 	*(type *)dest = (type)get_user_stack_nth(regs,			\
 					      ((unsigned long)offset)); \
@@ -120,8 +120,8 @@
 #define fetch_stack_string_size	NULL
 
 #define DEFINE_FETCH_memory(type)					\
-static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
-						void *addr, void *dest) \
+static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,		\
+					  void *addr, void *dest)	\
 {									\
 	type retval;							\
 	void __user *vaddr = (void __force __user *) addr;		\
@@ -136,8 +136,8 @@
  * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
  * length and relative data location.
  */
-static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
-						      void *addr, void *dest)
+static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
+					    void *addr, void *dest)
 {
 	long ret;
 	u32 rloc = *(u32 *)dest;
@@ -158,8 +158,8 @@
 	}
 }
 
-static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
-						      void *addr, void *dest)
+static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
+						 void *addr, void *dest)
 {
 	int len;
 	void __user *vaddr = (void __force __user *) addr;
@@ -184,8 +184,8 @@
 }
 
 #define DEFINE_FETCH_file_offset(type)					\
-static __kprobes void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,\
-					void *offset, void *dest) 	\
+static void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,	\
+					       void *offset, void *dest)\
 {									\
 	void *vaddr = (void *)translate_user_vaddr(offset);		\
 									\