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SubjectRe: [RFC][PATCH 3/5] timekeeping: Avoid possible deadlock from clock_was_set_delayed
On 12/11/2013 02:11 PM, John Stultz wrote:
> As part of normal operaions, the hrtimer subsystem frequently calls
> into the timekeeping code, creating a locking order of
> hrtimer locks -> timekeeping locks
> clock_was_set_delayed() was suppoed to allow us to avoid deadlocks
> between the timekeeping the hrtimer subsystem, so that we could
> notify the hrtimer subsytem the time had changed while holding
> the timekeeping locks. This was done by scheduling delayed work
> that would run later once we were out of the timekeeing code.
> But unfortunately the lock chains are complex enoguh that in
> scheduling delayed work, we end up eventually trying to grab
> an hrtimer lock.
> Sasha Levin noticed this in testing when the new seqlock lockdep
> enablement triggered the following (somewhat abrieviated) message:


This seems to work for me, I don't see the lockdep spew anymore.

Tested-by: Sasha Levin <>


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