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