Commit:     746976a301ac9c9aa10d7d42454f8d6cdad8ff2b
Parent:     872aad45d6174570dd2e1defc3efee50f2cfcc72
Author:     Thomas Gleixner <[EMAIL PROTECTED]>
AuthorDate: Tue Jul 3 20:05:20 2007 +0200
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Tue Jul 3 13:54:27 2007 -0700

    NTP: remove clock_was_set() call to prevent deadlock
    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
    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: Thomas Gleixner <[EMAIL PROTECTED]>
    Acked-by: Ingo Molnar <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
 kernel/time/ntp.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 87aa5ff..cf53bb5 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -122,7 +122,6 @@ void second_overflow(void)
                        time_state = TIME_OOP;
-                       clock_was_set();
                        printk(KERN_NOTICE "Clock: inserting leap second "
                                        "23:59:60 UTC\n");
@@ -137,7 +136,6 @@ void second_overflow(void)
                        time_state = TIME_WAIT;
-                       clock_was_set();
                        printk(KERN_NOTICE "Clock: deleting leap second "
                                        "23:59:59 UTC\n");
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