-
Bug
-
Resolution: Unresolved
-
Normal
-
4.21
-
None
-
None
-
False
-
-
None
-
Important
-
None
-
x86_64
-
2026-01-05: Solved in firmware 4.91; How do we track and/or release-note this?
-
None
-
None
-
CNF RAN Sprint 281, CNF RAN Sprint 282
-
2
-
None
-
None
-
None
-
None
-
None
-
None
-
None
Description of problem:
After simulating loss of GNSS sync then simulating recovery of GNSS sync, the DPLL flips between locked and holdover for ~15 minutes before everything reaches a stable state of locked. This was encountered using a machine with a GM profile with the ntpfailover plugin and an additional OC profile without phc2sys running.
Version-Release number of selected component (if applicable):
linuxptp-daemon 202512011821.p2.g3008622.assembly.stream.el9
How reproducible:
seems pretty consistent, but not 100%
Steps to Reproduce:
1. Simulate GNSS loss using ubxtool -P 29.20 -w 1 -v 3 -z CFG-NAVSPG-INFIL_NCNOTHRS,50,1
2. A few minutes later, simulate GNSS recovery using ubxtool -P 29.20 -w 1 -v 3 -z CFG-NAVSPG-INFIL_NCNOTHRS,0,1
3. Observe linuxptp-daemon logs showing alternating between DPLL locked and holdover for 15+ minutes
Actual results:
DPLL flips between holdover and locked for 15 minutes
Expected results:
DPLL locks and system quickly reaches stable state
Additional info:
