Commit c5138675 authored by Steven Rostedt's avatar Steven Rostedt Committed by Ingo Molnar
Browse files

ftrace: do not enclose logic in WARN_ON 



In ftrace, logic is defined in the WARN_ON_ONCE, which can become a
nop with some configs. This patch fixes it.

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 3e10e879

arch/x86/kernel/ftrace.c

+4 −2
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code, 
		   unsigned char *new_code)

{

	unsigned char replaced[MCOUNT_INSN_SIZE];

	int ret;



	/*

	 * Note: Due to modules and __init, code can
@@ -77,8 +78,9 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code, 
	if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0)

		return 2;



	WARN_ON_ONCE(__copy_to_user_inatomic((char __user *)ip, new_code,

				    MCOUNT_INSN_SIZE));

	ret = __copy_to_user_inatomic((char __user *)ip, new_code,

					MCOUNT_INSN_SIZE);

	WARN_ON_ONCE(ret);



	sync_core();