[PATCH 0/3] [QUANTAL] (pre-upstream) Potential fix for leapsecond caused futex issue

[Tim Gardner]

On 07/05/2012 10:08 AM, Brad Figg wrote:
> BugLink: http://bugs.launchpad.net/bugs/1020285
> 
> These patches are not yet in Linus' tree. Given that there will not be
> an additional leap-second added for some time to come, it may be better
> to just wait for these patches to reach Linus' tree.
> 
> John Stultz <john.stultz at linaro.org> has put together a 3 patch set to
> address the leapsecond bug that was encountered this past weekend by
> some sites.
> 
> This set has had some testing by a few people. This patch set in in
> the process of being reviewed upstream on lkml. I have been running
> a Quantal kernel with these patches applied. I am able to detect the
> issue with an unpatched kernel. I ran the leap-second test app and
> stress on a server system for 24+ hours without detecting the leap-second
> issue. The patchset has also received an ack by an upstream tester
> that had found issues with previous versions of this patcheset.
> 
> The following mailing list thread covers this patch set and the discussions
> around them:
>     https://lkml.org/lkml/2012/7/4/78
> 
> John Stultz (3):
>   hrtimer: Fix clock_was_set so it is safe to call from irq context
>   time: Fix leapsecond triggered hrtimer/futex load spike issue
>   hrtimer: Update hrtimer base offsets each hrtimer_interrupt
> 
>  include/linux/hrtimer.h   |    3 +++
>  kernel/hrtimer.c          |   31 +++++++++++++++++++++++++++----
>  kernel/time/timekeeping.c |   38 ++++++++++++++++++++++++++++++++++++++
>  3 files changed, 68 insertions(+), 4 deletions(-)
> 

When accepted upstream we should definitely backport them to the
affected LTS kernels since leap seconds happen approximately twice per year.

rtg
-- 
Tim Gardner tim.gardner at canonical.com