4.4-stable review patch.  If anyone has any objections, please let me know.

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

From: John Stultz <[email protected]>

[ Upstream commit 1416270f4a1ae83ea84156ceba19a66a8f88be1f ]

In the past we've warned when ADJ_OFFSET was in progress, usually
caused by ntpd or some other time adjusting daemon running in non
steady sate, which can cause the skew calculations to be
incorrect.

Thus, this patch checks to see if the clock was being adjusted
when we fail so that we don't cause false negatives.

Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Miroslav Lichvar <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: Stephen Boyd <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: [email protected]
Suggested-by: Miroslav Lichvar <[email protected]>
Signed-off-by: John Stultz <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
v2: Widened the checks to look for other clock adjustments that
    could happen, as suggested by Miroslav
v3: Fixed up commit message
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 tools/testing/selftests/timers/raw_skew.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/tools/testing/selftests/timers/raw_skew.c
+++ b/tools/testing/selftests/timers/raw_skew.c
@@ -146,6 +146,11 @@ int main(int argv, char **argc)
        printf(" %lld.%i(act)", ppm/1000, abs((int)(ppm%1000)));
 
        if (llabs(eppm - ppm) > 1000) {
+               if (tx1.offset || tx2.offset ||
+                   tx1.freq != tx2.freq || tx1.tick != tx2.tick) {
+                       printf("        [SKIP]\n");
+                       return ksft_exit_skip("The clock was adjusted 
externally. Shutdown NTPd or other time sync daemons\n");
+               }
                printf("        [FAILED]\n");
                return ksft_exit_fail();
        }


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