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SubjectRe: [PATCH] NTP: remove clock_was_set() call to prevent deadlock
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On Tue, 2007-07-03 at 20:05 +0200, Thomas Gleixner wrote:
> The clock_was_set() call in seconds_overflow() which happens only when
> leap seconds are inserted / deleted is wrong in two aspects:
>
> 1. it results in a call to on_each_cpu() with interrupts disabled
> 2. it is potential deadlock source vs. call_lock in smp_call_function()
>
> The only possible side effect of the removal might be, that an absolute
> CLOCK_REALTIME timer fires 1 second too late, in the rare case of leap
> second deletion and an absolute CLOCK_REALTIME timer which expires in
> the affected time frame. It will never fire too early.
>
> This was probably observed by the reporter of a June 30th -> July 1st
> hang: http://lkml.org/lkml/2007/7/3/

Ooops, missed the full reference:

http://lkml.org/lkml/2007/7/3/103

tglx


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