starfive_wdt_pm_start() takes a runtime PM reference with
pm_runtime_get_sync(), which increments the usage counter even when it
fails, and returns the error without dropping it again.  The watchdog
core does not invoke the stop callback when start fails, so the
reference taken on the error path is leaked.

Use pm_runtime_resume_and_get() instead, which keeps the usage counter
balanced when the resume fails.

Fixes: db728ea9c7be ("drivers: watchdog: Add StarFive Watchdog driver")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/watchdog/starfive-wdt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/starfive-wdt.c b/drivers/watchdog/starfive-wdt.c
index af55adc4a3c6..5a3254c83d3b 100644
--- a/drivers/watchdog/starfive-wdt.c
+++ b/drivers/watchdog/starfive-wdt.c
@@ -371,7 +371,7 @@ static void starfive_wdt_stop(struct starfive_wdt *wdt)
 static int starfive_wdt_pm_start(struct watchdog_device *wdd)
 {
 	struct starfive_wdt *wdt = watchdog_get_drvdata(wdd);
-	int ret = pm_runtime_get_sync(wdd->parent);
+	int ret = pm_runtime_resume_and_get(wdd->parent);
 
 	if (ret < 0)
 		return ret;
-- 
2.34.1

On Wed, Sep 16, 2026 at 05:07:04PM +0000, Wentao Liang wrote:
> starfive_wdt_pm_start() takes a runtime PM reference with
> pm_runtime_get_sync(), which increments the usage counter even when it
> fails, and returns the error without dropping it again.  The watchdog
> core does not invoke the stop callback when start fails, so the
> reference taken on the error path is leaked.
> 
> Use pm_runtime_resume_and_get() instead, which keeps the usage counter
> balanced when the resume fails.
> 
> Fixes: db728ea9c7be ("drivers: watchdog: Add StarFive Watchdog driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>

Applied.

Thanks,
Guenter