The following commit has been merged into the timers/urgent branch of tip:

Commit-ID: e09784a8a751e539dffc94d43bc917b0ac1e934a Gitweb: https://git.kernel.org/tip/e09784a8a751e539dffc94d43bc917b0ac1e934a Author: Alexandre Belloni alexandre.belloni@bootlin.com AuthorDate: Tue, 11 May 2021 03:45:16 +02:00 Committer: Thomas Gleixner tglx@linutronix.de CommitterDate: Tue, 11 May 2021 21:28:04 +02:00

alarmtimer: Check RTC features instead of ops

RTC drivers used to leave .set_alarm() NULL in order to signal the RTC device doesn't support alarms. The drivers are now clearing the RTC_FEATURE_ALARM bit for that purpose in order to keep the rtc_class_ops structure const. So now, .set_alarm() is set unconditionally and this possibly causes the alarmtimer code to select an RTC device that doesn't support alarms.

Test RTC_FEATURE_ALARM instead of relying on ops->set_alarm to determine whether alarms are available.

Fixes: 7ae41220ef58 ("rtc: introduce features bitfield") Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210511014516.563031-1-alexandre.belloni@bootlin....

--- kernel/time/alarmtimer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index bea9d08..5897828 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -92,7 +92,7 @@ static int alarmtimer_rtc_add_device(struct device *dev, if (rtcdev) return -EBUSY;

- if (!rtc->ops->set_alarm) + if (!test_bit(RTC_FEATURE_ALARM, rtc->features)) return -1; if (!device_may_wakeup(rtc->dev.parent)) return -1;