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[PATCH] kernel/extable.c: mark core_kernel_text notrace

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core_kernel_text is used by MIPS in its function graph trace processing,
so having this method traced leads to an infinite set of recursive calls
such as:

[    2.972075] Call Trace:
[    2.972111]
[    2.976731] [<80506584>] ftrace_return_to_handler+0x50/0x128
[    2.983379] [<8045478c>] core_kernel_text+0x10/0x1b8
[    2.989146] [<804119b8>] prepare_ftrace_return+0x6c/0x114
[    2.995402] [<80411b2c>] ftrace_graph_caller+0x20/0x44
[    3.001362] [<80411b60>] return_to_handler+0x10/0x30
[    3.007159] [<80411b50>] return_to_handler+0x0/0x30
[    3.012827] [<80411b50>] return_to_handler+0x0/0x30
[    3.018621] [<804e589c>] ftrace_ops_no_ops+0x114/0x1bc
[    3.024602] [<8045478c>] core_kernel_text+0x10/0x1b8
[    3.030377] [<8045478c>] core_kernel_text+0x10/0x1b8
[    3.036140] [<8045478c>] core_kernel_text+0x10/0x1b8
[    3.041915] [<804e589c>] ftrace_ops_no_ops+0x114/0x1bc
[    3.047923] [<8045478c>] core_kernel_text+0x10/0x1b8
[    3.053682] [<804119b8>] prepare_ftrace_return+0x6c/0x114
[    3.059938] [<80411b2c>] ftrace_graph_caller+0x20/0x44
(...)

Mark the function notrace to avoid it being traced.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
---
 kernel/extable.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/extable.c b/kernel/extable.c
index 2676d7f..4efaf26 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -70,7 +70,7 @@ static inline int init_kernel_text(unsigned long addr)
 	return 0;
 }
 
-int core_kernel_text(unsigned long addr)
+int notrace core_kernel_text(unsigned long addr)
 {
 	if (addr >= (unsigned long)_stext &&
 	    addr < (unsigned long)_etext)
-- 
2.7.4

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[PATCH] kernel/extable.c: mark core_kernel_text notrace Marcin Nowakowski <marcin.nowakowski@imgtec.com> - 2017-06-21 09:10 +0200
  Re: [PATCH] kernel/extable.c: mark core_kernel_text notrace Masami Hiramatsu <mhiramat@kernel.org> - 2017-06-22 12:30 +0200
  Re: [PATCH] kernel/extable.c: mark core_kernel_text notrace Thomas Gleixner <tglx@linutronix.de> - 2017-06-23 00:20 +0200
  Re: [PATCH] kernel/extable.c: mark core_kernel_text notrace Steven Rostedt <rostedt@goodmis.org> - 2017-06-23 00:20 +0200

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