ftrace: do not enclose logic in WARN_ON (c5138675) · Commits · 戴 / test

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:

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();