diff mbox series

[REVIEW,1/2] watchdog: extend the mutex-protected section in watchdog_cdev_unregister()

Message ID 20220818020624.2386475-1-aklimov@redhat.com
State New
Headers show
Series [REVIEW,1/2] watchdog: extend the mutex-protected section in watchdog_cdev_unregister() | expand

Commit Message

Alexey Klimov Aug. 18, 2022, 2:06 a.m. UTC
watchdog_stop() should be called with wd_data->lock mutex locked.
Updates to wdd->status also occur under this look throughout the
watchdog_dev.c as well as functions that deal with pretimeout hrtimer
like watchdog_hrtimer_pretimeout_stop() here.

Signed-off-by: Alexey Klimov <aklimov@redhat.com>
---
 drivers/watchdog/watchdog_dev.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 54903f3c851e..804236a094f6 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -1095,6 +1095,8 @@  static void watchdog_cdev_unregister(struct watchdog_device *wdd)
 		old_wd_data = NULL;
 	}
 
+	mutex_lock(&wd_data->lock);
+
 	if (watchdog_active(wdd) &&
 	    test_bit(WDOG_STOP_ON_UNREGISTER, &wdd->status)) {
 		watchdog_stop(wdd);
@@ -1102,7 +1104,6 @@  static void watchdog_cdev_unregister(struct watchdog_device *wdd)
 
 	watchdog_hrtimer_pretimeout_stop(wdd);
 
-	mutex_lock(&wd_data->lock);
 	wd_data->wdd = NULL;
 	wdd->wd_data = NULL;
 	mutex_unlock(&wd_data->lock);