The stress test scenario is: "umount -f" of an active FS: 20190211 12:26:07 all (1/1): pfl3.sh panic: handle_written_inodeblock: live inodedep 0xfffff80261dbc400 cpuid = 45 time = 1549884371 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe010ac22000 vpanic() at vpanic+0x1b4/frame 0xfffffe010ac22060 panic() at panic+0x43/frame 0xfffffe010ac220c0 handle_written_inodeblock() at handle_written_inodeblock+0x669/frame 0xfffffe010ac22110 softdep_disk_write_complete() at softdep_disk_write_complete+0x462/frame 0xfffffe010ac22170 bufdone() at bufdone+0x3bb/frame 0xfffffe010ac221f0 g_io_deliver() at g_io_deliver+0x298/frame 0xfffffe010ac22240 g_io_deliver() at g_io_deliver+0x298/frame 0xfffffe010ac22290 md_kthread() at md_kthread+0x258/frame 0xfffffe010ac222f0 fork_exit() at fork_exit+0x84/frame 0xfffffe010ac22330 fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe010ac22330 --- trap 0, rip = 0, rsp = 0, rbp = 0 --- KDB: enter: panic [ thread pid 35083 tid 101903 ] Stopped at kdb_enter+0x3b: movq $0,kdb_why db> x/s version version: FreeBSD 13.0-CURRENT #0 r343968: Sun Feb 10 20:35:52 CET 2019\012 pho@flix1a.netperf.freebsd.org:/usr/src/sys/amd64/compile/PHO\012 db> https://people.freebsd.org/~pho/stress/log/pfl3.txt