]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
timekeeping: Fix cross-timestamp interpolation on counter wrap
authorPeter Hilber <peter.hilber@opensynergy.com>
Mon, 18 Dec 2023 07:38:39 +0000 (08:38 +0100)
committerSasha Levin <sashal@kernel.org>
Tue, 26 Mar 2024 22:19:19 +0000 (18:19 -0400)
commitc56317c7ed4655f462d4af09e40e56e5b7a5329e
tree6d89599f455d319a4dc8fd8ced4a31fa76314a9a
parent835ae8a07a2a3da13ca3c60a5c873fac0362e89e
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@opensynergy.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/r/20231218073849.35294-2-peter.hilber@opensynergy.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
kernel/time/timekeeping.c