Linux kernel源码中关闭内核log

1.kernel/kernel/printk/printk.c
static void call_console_drivers(const char *ext_text, size_t ext_len,
				 const char *text, size_t len)
{
	struct console *con;

	trace_console_rcuidle(text, len);

	if (!console_drivers)
		return;

	for_each_console(con) {
		if (exclusive_console && con != exclusive_console)
			continue;
		if (!(con->flags & CON_ENABLED))
			continue;
		if (!con->write)
			continue;
		if (!cpu_online(smp_processor_id()) &&
		    !(con->flags & CON_ANYTIME))
			continue;
		if (con->flags & CON_EXTENDED)
			con->write(con, ext_text, ext_len);
		else
			con->write(con, text, len);
	}
}

修改为：
static void call_console_drivers(const char *ext_text, size_t ext_len,
				 const char *text, size_t len){
+   return;   

	struct console *con;

	trace_console_rcuidle(text, len);

	if (!console_drivers)
		return;

	for_each_console(con) {
		if (exclusive_console && con != exclusive_console)
			continue;
		if (!(con->flags & CON_ENABLED))
			continue;
		if (!con->write)
			continue;
		if (!cpu_online(smp_processor_id()) &&
		    !(con->flags & CON_ANYTIME))
			continue;
		if (con->flags & CON_EXTENDED)
			con->write(con, ext_text, ext_len);
		else
			con->write(con, text, len);
	}
}