Re: [PATCH -stable] ntp: Correct TAI offset during leap second

[John Stultz <johnstul@us.ibm.com>]

On 06/15/2012 11:56 AM, John Stultz wrote:
> Hey Greg,
>     Forgot to cc stable on this one. Thanks to Dave Jones for noticing!
> -john

Gah. Thunderbird's preformat wrecked that one. Sorry.
Here it is again.
-john

------------------

From: Richard Cochran<richardcochran@gmail.com>

commit dd48d708ff3e917f6d6b6c2b696c3f18c019feed upstream.

When repeating a UTC time value during a leap second (when the UTC
time should be 23:59:60), the TAI timescale should not stop. The kernel
NTP code increments the TAI offset one second too late. This patch fixes
the issue by incrementing the offset during the leap second itself.

Signed-off-by: Richard Cochran<richardcochran@gmail.com>
Signed-off-by: John Stultz<john.stultz@linaro.org>
---
  kernel/time/ntp.c |    2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index f03fd83..e8c8671 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -412,6 +412,7 @@ int second_overflow(unsigned long secs)
  		if (secs % 86400 == 0) {
  			leap = -1;
  			time_state = TIME_OOP;
+			time_tai++;
  			printk(KERN_NOTICE
  				"Clock: inserting leap second 23:59:60 UTC\n");
  		}
@@ -426,7 +427,6 @@ int second_overflow(unsigned long secs)
  		}
  		break;
  	case TIME_OOP:
-		time_tai++;
  		time_state = TIME_WAIT;
  		break;

-- 
1.7.9.5