[PATCH -tip v3 02/10] x86/kprobes: Move trampoline code into RODATA

Masami Hiramatsu
2019-02-12T16:12:13Z

Move optprobe trampoline code into RODATA since it is
not executed, but copied and modified to be used on
a trampoline buffer.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
arch/x86/kernel/kprobes/opt.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 544bd41a514c..f14262952015 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -97,6 +97,7 @@ static void synthesize_set_arg1(kprobe_opcode_t *addr, unsigned long val)
}

asm (
+ ".pushsection .rodata\n"
"optprobe_template_func:\n"
".global optprobe_template_entry\n"
"optprobe_template_entry:\n"
@@ -136,16 +137,10 @@ asm (
#endif
".global optprobe_template_end\n"
"optprobe_template_end:\n"
- ".type optprobe_template_func, @function\n"
- ".size optprobe_template_func, .-optprobe_template_func\n");
+ ".popsection\n");

void optprobe_template_func(void);
STACK_FRAME_NON_STANDARD(optprobe_template_func);
-NOKPROBE_SYMBOL(optprobe_template_func);
-NOKPROBE_SYMBOL(optprobe_template_entry);
-NOKPROBE_SYMBOL(optprobe_template_val);
-NOKPROBE_SYMBOL(optprobe_template_call);
-NOKPROBE_SYMBOL(optprobe_template_end);

#define TMPL_MOVE_IDX \
((long)optprobe_template_val - (long)optprobe_template_entry)