1. 04 7月, 2007 1 次提交
    • T
      NTP: remove clock_was_set() call to prevent deadlock · 746976a3
      Thomas Gleixner 提交于
      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/2007/7/3/103
      
      A similar problem was observed by Dave Jones, who provided a screen shot
      with a lockdep back trace, which allowed to analyse the problem.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      746976a3
  2. 03 7月, 2007 17 次提交
  3. 02 7月, 2007 22 次提交