From 0fa37512eb747e4ffdcf367274f9e72845f1bca4 Mon Sep 17 00:00:00 2001 From: David Arcari Date: Thu, 3 Sep 2026 14:20:29 -0400 Subject: [PATCH] watchdog: fix hrtimer start when pretimeout is zero Per the watchdog API, a pretimeout value of 0 disables the feature. However, watchdog_hrtimer_pretimeout_start() fails to verify if the pretimeout is non-zero before arming the timer. This omission inadvertently starts the software pretimeout timer, which could result in the pretimeout handler executing incorrectly when the watchdog timeout is reached. Fix this by adding a check for wdd->pretimeout before calling hrtimer_start(), ensuring the disabled state is respected. Fixes: 7b7d2fdc8c3e ("watchdog: Add hrtimer-based pretimeout feature") Signed-off-by: David Arcari Link: https://patch.msgid.link/20260903182029.936030-1-darcari@redhat.com Signed-off-by: Guenter Roeck --- drivers/watchdog/watchdog_hrtimer_pretimeout.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/watchdog/watchdog_hrtimer_pretimeout.c b/drivers/watchdog/watchdog_hrtimer_pretimeout.c index fbc7eecd8b20..49a05ea60c97 100644 --- a/drivers/watchdog/watchdog_hrtimer_pretimeout.c +++ b/drivers/watchdog/watchdog_hrtimer_pretimeout.c @@ -30,6 +30,7 @@ void watchdog_hrtimer_pretimeout_init(struct watchdog_device *wdd) void watchdog_hrtimer_pretimeout_start(struct watchdog_device *wdd) { if (!(wdd->info->options & WDIOF_PRETIMEOUT) && + wdd->pretimeout && !watchdog_pretimeout_invalid(wdd, wdd->pretimeout)) hrtimer_start(&wdd->wd_data->pretimeout_timer, ktime_set(wdd->timeout - wdd->pretimeout, 0),