kernel/drivers/rtc/interface.c, branch linux-4.1.y

rtc: interface: Validate alarm-time before handling rollover

2018-05-23T01:36:27Z

[ Upstream commit da96aea0ed177105cb13ee83b328f6c61e061d3f ] In function __rtc_read_alarm() its possible for an alarm time-stamp to be invalid even after replacing missing components with current time-stamp. The condition 'alarm->time.tm_year < 70' will trigger this case and will cause the call to 'rtc_tm_to_time64(&alarm->time)' return a negative value for variable t_alm. While handling alarm rollover this negative t_alm (assumed to seconds offset from '1970-01-01 00:00:00') is converted back to rtc_time via rtc_time64_to_tm() which results in this error log with seemingly garbage values: "rtc rtc0: invalid alarm value: -2-1--1041528741 2005511117:71582844:32" This error was generated when the rtc driver (rtc-opal in this case) returned an alarm time-stamp of '00-00-00 00:00:00' to indicate that the alarm is disabled. Though I have submitted a separate fix for the rtc-opal driver, this issue may potentially impact other existing/future rtc drivers. To fix this issue the patch validates the alarm time-stamp just after filling up the missing datetime components and if rtc_valid_tm() still reports it to be invalid then bails out of the function without handling the rollover. Reported-by: Steve Best Signed-off-by: Vaibhav Jain Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

rtc: set the alarm to the next expiring timer

2018-03-01T00:32:16Z

[ Upstream commit 74717b28cb32e1ad3c1042cafd76b264c8c0f68d ] If there is any non expired timer in the queue, the RTC alarm is never set. This is an issue when adding a timer that expires before the next non expired timer. Ensure the RTC alarm is set in that case. Fixes: 2b2f5ff00f63 ("rtc: interface: ignore expired timers when enqueuing new timers") Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

rtc: interface: ignore expired timers when enqueuing new timers

2018-01-17T17:24:37Z

[ Upstream commit 2b2f5ff00f63847d95adad6289bd8b05f5983dd5 ] This patch fixes a RTC wakealarm issue, namely, the event fires during hibernate and is not cleared from the list, causing hwclock to block. The current enqueuing does not trigger an alarm if any expired timers already exist on the timerqueue. This can occur when a RTC wake alarm is used to wake a machine out of hibernate and the resumed state has old expired timers that have not been removed from the timer queue. This fix skips over any expired timers and triggers an alarm if there are no pending timers on the timerqueue. Note that the skipped expired timer will get reaped later on, so there is no need to clean it up immediately. The issue can be reproduced by putting a machine into hibernate and waking it with the RTC wakealarm. Running the example RTC test program from tools/testing/selftests/timers/rtctest.c after the hibernate will block indefinitely. With the fix, it no longer blocks after the hibernate resume. BugLink: http://bugs.launchpad.net/bugs/1333569 Signed-off-by: Colin Ian King Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

drivers/rtc/interface.c: __rtc_read_time: reduce log level

2015-04-17T13:04:01Z

__rtc_read_time logs should be debug logs instead of error logs. For example, when the RTC clock is not set, it's not really useful to print a kernel error log every time someone tries to read the clock: ~ # hwclock -r [ 604.508263] rtc rtc0: read_time: fail to read hwclock: RTC_RD_TIME: Invalid argument If there's a real error, it's likely that lower level or higher level code will tell it anyway. Make these logs debug logs, and also print the error code for the read failure. Signed-off-by: Aaro Koskinen Acked-by: Alexandre Belloni Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/rtc: Provide y2038 safe rtc_class_ops.set_mmss() replacement

2015-04-03T06:18:24Z

Currently the rtc_class_op's set_mmss() function takes a 32-bit second value (on 32-bit systems), which is problematic for dates past y2038. This patch provides a safe version named set_mmss64() using y2038 safe time64_t. After this patch, set_mmss() is deprecated and all its users will be fixed to use set_mmss64(), it can be removed when having no users. Signed-off-by: Xunlei Pang [jstultz: Add whitespace fix for checkpatch] Signed-off-by: John Stultz Acked-by: Alessandro Zummo Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1427945681-29972-8-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar

rtc: Update interface.c to use y2038-safe time interfaces

2015-01-24T01:21:55Z

Currently, interface.c uses y2038 problematic rtc_tm_to_time() and rtc_time_to_tm(). So replace them with their corresponding y2038-safe versions: rtc_tm_to_time64() and rtc_time64_to_tm(). Cc: pang.xunlei Cc: Arnd Bergmann Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Xunlei Pang Signed-off-by: John Stultz

rtc: refine rtc_timer_do_work() to consider other set alarm failures

2014-12-11T01:41:16Z

rtc_timer_do_work() only judges -ETIME failure of__rtc_set_alarm(), but doesn't handle other failures like -EIO, -EBUSY, etc. If there is a failure other than -ETIME, the next rtc_timer will stay in the timerqueue. Then later rtc_timers will be enqueued directly because they have a later expires time, so the alarm irq will never be programmed. When such failures happen, this patch will retry __rtc_set_alarm(), if still can't program the alarm time, it will remove current rtc_timer from timerqueue and fetch next one, thus preventing it from affecting other rtc timers. Signed-off-by: Xunlei Pang Cc: Alessandro Zummo Cc: John Stultz Cc: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/rtc/interface.c: check the validation of rtc_time in __rtc_read_time

2014-12-11T01:41:13Z

Some rtc devices always return '0' when rtc_class_ops.read_time is called. So if rtc_time isn't verified in callback, rtc interface cannot know whether rtc_time is valid. Check rtc_time by using 'rtc_valid_tm' in '__rtc_read_time'. And add the message for debugging. Signed-off-by: Hyogi Gim Cc: Alessandro Zummo Cc: John Stultz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/rtc/interface.c: check the error after __rtc_read_time()

2014-08-08T22:57:19Z

In __rtc_set_alarm(), the error after __rtc_read_time() is not checked. If rtc device fail to read time, we cannot guarantee the following process. Add the verification code for returned __rtc_read_time() error. Signed-off-by: Hyogi Gim Acked-by: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/rtc/interface.c: fix infinite loop in initializing the alarm

2014-06-06T23:08:06Z

In __rtc_read_alarm(), if the alarm time retrieved by rtc_read_alarm_internal() from the device contains invalid values (e.g. month=2,mday=31) and the year not set (=-1), the initialization will loop infinitely because the year-fixing loop expects the time being invalid due to leap year. Fix reduces the loop to the leap years and adds final validity check. Signed-off-by: Ales Novak Acked-by: Alessandro Zummo Reported-by: Jiri Bohac Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds