Re: [PATCH 0/5 v2] Fixes for leapsecond expiring early ABS_TIME CLOCK_REALTIME timers

[Dave Jones <davej@codemonkey.org.uk>]

On Fri, Jun 12, 2015 at 10:55:57AM -0400, Prarit Bhargava wrote:
 
 > >  > This series has only had limited testing, so I wanted to send
 > >  > it out for initial review and comment. Folks can grab this tree
 > >  > via git for testing here:
 > >  > https://git.linaro.org/people/john.stultz/linux.git dev/early-leap-timer
 > > 
 > > Any idea how far back this reaches ? Ie, which longterm stable releases
 > > might be affected by this ?
 > 
 > Likely occurs in any kernel after NOHZ was introduced.

At least on 3.14, it seems to happen even if NOHZ is disabled.

# ./leap -i 5 -s
Setting time to speed up testing
Running for 5 iterations. Press ctrl-c to stop

Setting time to Sat Jun 13 23:59:50 2015
Scheduling leap second for Sun Jun 14 00:00:00 2015
Setting timer for Sun Jun 14 00:00:00 2015
Sat Jun 13 23:59:57 2015 +     55 us (1)	TIME_INS
Sat Jun 13 23:59:57 2015 + 500127 us (1)	TIME_INS
Sat Jun 13 23:59:58 2015 +    189 us (1)	TIME_INS
Sat Jun 13 23:59:58 2015 + 500250 us (1)	TIME_INS
Sat Jun 13 23:59:59 2015 +    312 us (1)	TIME_INS
Sat Jun 13 23:59:59 2015 + 500372 us (1)	TIME_INS
Sun Jun 14 00:00:00 2015 +      3 us (1)	TIME_INS - TIMER FIRED
Error: Incorrect NTP state?
Sun Jun 14 00:00:00 2015 +     12 us (1)	TIME_INS
Sat Jun 13 23:59:59 2015 + 500068 us (2)	TIME_OOP
Sun Jun 14 00:00:00 2015 +    130 us (2)	TIME_OOP
Sun Jun 14 00:00:00 2015 + 500190 us (2)	TIME_WAIT
Sun Jun 14 00:00:01 2015 +    256 us (2)	TIME_WAIT
Sun Jun 14 00:00:01 2015 + 500315 us (2)	TIME_WAIT
Sun Jun 14 00:00:02 2015 +    376 us (2)	TIME_WAIT
Leap complete
Errors observed



	Dave