(console lines preceding the watchdog flood, captured from the serial
 console during the same run:)

login: DF67: entering REAL cam_periph_ioctl(CAMGETPASSTHRU) on fabricated periph with EMPTY device periph list -- expect non-terminating loop (CAM_GDEVLIST_ERROR forever)
(then, every 5 seconds for the whole observation window:)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)
DF67: spin still running (thread df67spin); SIM-lock NOWAIT probe rc=16 (LOCK STILL HELD by spinner)