panic: sx lock still held
cpuid = 0
time = 1560397707
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe001f6d6760
vpanic() at vpanic+0x1e0/frame 0xfffffe001f6d67c0
panic() at panic+0x43/frame 0xfffffe001f6d6820
sx_destroy() at sx_destroy+0x5e/frame 0xfffffe001f6d6840
solisten_proto() at solisten_proto+0xde/frame 0xfffffe001f6d68a0
tcp6_usr_listen() at tcp6_usr_listen+0x1cc/frame 0xfffffe001f6d6900
solisten() at solisten+0x7a/frame 0xfffffe001f6d6940
kern_listen() at kern_listen+0x132/frame 0xfffffe001f6d6980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe001f6d6ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe001f6d6ab0
--- syscall (198, FreeBSD ELF64, nosys), rip = 0x4131fa, rsp = 0x7fffdfffdf38, rbp = 0x2 ---
KDB: enter: panic
[ thread pid 848 tid 100139 ]
Stopped at      kdb_enter+0x6a: movq    $0,kdb_why