kernel: write to all registered consoles with printk()

kernel/console.c

@@ -29,11 +29,23 @@ kern_status_t console_unregister(struct console *con)
 	spin_lock_irqsave(&consoles_lock, &flags);
 
 	queue_delete(&consoles, &con->c_list);
-	
+
 	spin_unlock_irqrestore(&consoles_lock, flags);
 	return KERN_OK;
 }
 
+struct queue *get_consoles(unsigned long *flags)
+{
+	spin_lock_irqsave(&consoles_lock, flags);
+	return &consoles;
+}
+
+void put_consoles(struct queue *consoles, unsigned long flags)
+{
+	(void)consoles;
+	spin_unlock_irqrestore(&consoles_lock, flags);
+}
+
 void console_write(struct console *con, const char *s, unsigned int len)
 {
 	if (con->c_write) {

kernel/printk.c

@@ -21,11 +21,21 @@ static unsigned int log_buffer_writep = 0;
 
 static void flush_log_buffer(void)
 {
+	/*
 	if (!early_console) {
 		return;
 	}
-	
+
 	console_write(early_console, log_buffer + log_buffer_readp, log_buffer_writep - log_buffer_readp);
+	*/
+
+	unsigned long flags;
+	struct queue *consoles = get_consoles(&flags);
+	queue_foreach(struct console, con, consoles, c_list) {
+		console_write(con, log_buffer + log_buffer_readp, log_buffer_writep - log_buffer_readp);
+	}
+
+	put_consoles(consoles, flags);
 	log_buffer_readp = log_buffer_writep;
 }
 
@@ -41,7 +51,7 @@ static void save_log_message(const char *msg)
 		if (msg[i] == '\0') {
 			break;
 		}
-				   
+
 		log_buffer[log_buffer_writep++] = msg[i++];
 	}
 }
@@ -73,6 +83,6 @@ int printk(const char *format, ...)
 	spin_unlock_irqrestore(&log_buffer_lock, flags);
 
 	flush_log_buffer();
-	
+
         return 0;
 }