diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 6cc0db1bf522..3f129b45451a 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -684,7 +684,7 @@ again:
 
 	err = xenbus_switch_state(dev, XenbusStateConnected);
 	if (err)
-		xenbus_dev_fatal(dev, err, "switching to Connected state",
+		xenbus_dev_fatal(dev, err, "%s: switching to Connected state",
 				 dev->nodename);
 
 	return;
diff --git a/include/xen/hvc-console.h b/include/xen/hvc-console.h
index c3adde32669b..901724dc528d 100644
--- a/include/xen/hvc-console.h
+++ b/include/xen/hvc-console.h
@@ -6,11 +6,13 @@ extern struct console xenboot_console;
 #ifdef CONFIG_HVC_XEN
 void xen_console_resume(void);
 void xen_raw_console_write(const char *str);
+__attribute__((format(printf, 1, 2)))
 void xen_raw_printk(const char *fmt, ...);
 #else
 static inline void xen_console_resume(void) { }
 static inline void xen_raw_console_write(const char *str) { }
-static inline void xen_raw_printk(const char *fmt, ...) { }
+static inline __attribute__((format(printf, 1, 2)))
+void xen_raw_printk(const char *fmt, ...) { }
 #endif
 
 #endif	/* XEN_HVC_CONSOLE_H */
diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
index 5467369e0889..aceeca799fd7 100644
--- a/include/xen/xenbus.h
+++ b/include/xen/xenbus.h
@@ -223,7 +223,9 @@ int xenbus_free_evtchn(struct xenbus_device *dev, int port);
 
 enum xenbus_state xenbus_read_driver_state(const char *path);
 
+__attribute__((format(printf, 3, 4)))
 void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
+__attribute__((format(printf, 3, 4)))
 void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
 
 const char *xenbus_strstate(enum xenbus_state state);