panic: sbfree: m 0xfffff80004993600 !M_NOTREADY cpuid = 0 time = 1554031880 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe00212774c0 vpanic() at vpanic+0x1e0/frame 0xfffffe0021277520 panic() at panic+0x43/frame 0xfffffe0021277580 sbfree() at sbfree+0x1f4/frame 0xfffffe00212775c0 sbcut_internal() at sbcut_internal+0xf0/frame 0xfffffe0021277610 sbrelease_internal() at sbrelease_internal+0x9c/frame 0xfffffe0021277650 sofree() at sofree+0x492/frame 0xfffffe00212776b0 soclose() at soclose+0x5b3/frame 0xfffffe0021277730 _fdrop() at _fdrop+0x3a/frame 0xfffffe0021277760 closef() at closef+0x27d/frame 0xfffffe00212777f0 fdescfree_fds() at fdescfree_fds+0xbd/frame 0xfffffe0021277840 fdescfree() at fdescfree+0x58a/frame 0xfffffe0021277900 exit1() at exit1+0x780/frame 0xfffffe0021277970 sys_sys_exit() at sys_sys_exit+0xd/frame 0xfffffe0021277980 amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe0021277ab0 fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0021277ab0 --- syscall (1, FreeBSD ELF64, sys_sys_exit), rip = 0x44f32a, rsp = 0x7fffffffec58, rbp = 0x1 --- KDB: enter: panic [ thread pid 928 tid 100405 ] Stopped at kdb_enter+0x6a: movq $0,kdb_why