[PATCH] watchdog: Differentiate scenarios when watchdog is closed

From: Charles Haithcock

Date: Tue Sep 01 2026 - 17:43:39 EST


Presently, when a watchdog device is closed, we print "watchdog did not
stop" in a few different scenarios;

1. When nowayout is set
2. When the watchdog is able to close, has received the magic character
to stop, but fails to close in device-specific code paths
3. When userspace deliberately closes it without stopping it

For 1, we explicitly print we can not close because of nowayout. Nothing
differentiates the other two however.

This change adds a print to indicate the watchdog was closed while still
running.

Suggested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Charles Haithcock <chaithco@xxxxxxxxxx>
---

v1. Introduce change and modify logic to differentiate
v2. Simplify but still differentiate

drivers/watchdog/watchdog_dev.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index d7895009a2..937bdd4c92 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -305,6 +305,10 @@ static int watchdog_stop(struct watchdog_device *wdd)
if (wdd->ops->stop) {
clear_bit(WDOG_HW_RUNNING, &wdd->status);
err = wdd->ops->stop(wdd);
+ if (err < 0) {
+ pr_err("watchdog%d: Failed to stop watchdog: %pe\n", wdd->id,
+ ERR_PTR(err));
+ }
trace_watchdog_stop(wdd, err);
} else {
set_bit(WDOG_HW_RUNNING, &wdd->status);
--
2.55.0