On 8/1/21 12:56 AM, Jan Kiszka wrote:
From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> We must not pet a running watchdog when handle_boot_enabled is off because this will kick off automatic triggering before userland is running, defeating the purpose of the handle_boot_enabled control. Furthermore, don't ping in case watchdog_set_last_hw_keepalive was called incorrectly when the hardware watchdog is actually not running. Fixed: cef9572e9af3 ("watchdog: add support for adjusting last known HW keepalive time") Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
--- Changes to v1 ("watchdog: Respect handle_boot_enabled when setting last last_hw_keepalive"): - add watchdog_hw_running test - improve commit log drivers/watchdog/watchdog_dev.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 3bab32485273..6c73160386b9 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -1172,7 +1172,10 @@ int watchdog_set_last_hw_keepalive(struct watchdog_device *wdd, wd_data->last_hw_keepalive = ktime_sub(now, ms_to_ktime(last_ping_ms)); - return __watchdog_ping(wdd); + if (watchdog_hw_running(wdd) && handle_boot_enabled) + return __watchdog_ping(wdd); + + return 0; } EXPORT_SYMBOL_GPL(watchdog_set_last_hw_keepalive); -- 2.31.1