This is a note to let you know that I've just added the patch titled
timekeeping: Fix cross-timestamp interpolation on counter wrap
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
timekeeping-fix-cross-timestamp-interpolation-on-cou.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 810b340e3948befbdf5d6fa3577b57fcb5a50fa8
Author: Peter Hilber <peter.hilber@xxxxxxxxxxxxxxx>
Date: Mon Dec 18 08:38:39 2023 +0100
timekeeping: Fix cross-timestamp interpolation on counter wrap
[ Upstream commit 84dccadd3e2a3f1a373826ad71e5ced5e76b0c00 ]
cycle_between() decides whether get_device_system_crosststamp() will
interpolate for older counter readings.
cycle_between() yields wrong results for a counter wrap-around where after
< before < test, and for the case after < test < before.
Fix the comparison logic.
Fixes: 2c756feb18d9 ("time: Add history to cross timestamp interface supporting slower devices")
Signed-off-by: Peter Hilber <peter.hilber@xxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: John Stultz <jstultz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231218073849.35294-2-peter.hilber@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index d921c1b256cf5..985aa75eedb24 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1169,7 +1169,7 @@ static bool cycle_between(u64 before, u64 test, u64 after)
{
if (test > before && test < after)
return true;
- if (test < before && before > after)
+ if (before > after && (test > before || test < after))
return true;
return false;
}
