[PATCH] xen/xenbus: fix W=1 build warning in xenbus_va_dev_error function

From: jiang.peng9
Date: Tue Jun 17 2025 - 22:02:22 EST


From: Peng Jiang <jiang.peng9@xxxxxxxxxx>


This patch fixes a W=1 format-string warning reported by GCC 12.3.0

by annotating xenbus_switch_fatal() and xenbus_va_dev_error()

with the __printf attribute. The attribute enables compile-time

validation of printf-style format strings in these functions.


The original warning trace:

drivers/xen/xenbus/xenbus_client.c:304:9: warning: function 'xenbus_va_dev_error' might be

a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]


Signed-off-by: Peng Jiang <jiang.peng9@xxxxxxxxxx>

---

 drivers/xen/xenbus/xenbus_client.c | 2 ++

 1 file changed, 2 insertions(+)


diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c

index 51b3124b0d56..e73ec225d4a6 100644

--- a/drivers/xen/xenbus/xenbus_client.c

+++ b/drivers/xen/xenbus/xenbus_client.c

@@ -202,6 +202,7 @@ int xenbus_watch_pathfmt(struct xenbus_device *dev,

 }

 EXPORT_SYMBOL_GPL(xenbus_watch_pathfmt);

 

+__printf(4, 5)

 static void xenbus_switch_fatal(struct xenbus_device *, int, int,

                                const char *, ...);

 

@@ -287,6 +288,7 @@ int xenbus_frontend_closed(struct xenbus_device *dev)

 }

 EXPORT_SYMBOL_GPL(xenbus_frontend_closed);

 

+__printf(3, 0)

 static void xenbus_va_dev_error(struct xenbus_device *dev, int err,

                                const char *fmt, va_list ap)

 {

-- 

2.25.1