panic: Most recently used by tty cpuid = 1 time = 1557320204 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe001fa7c690 vpanic() at vpanic+0x1e0/frame 0xfffffe001fa7c6f0 panic() at panic+0x43/frame 0xfffffe001fa7c750 mtrash_ctor() at mtrash_ctor+0xed/frame 0xfffffe001fa7c790 uma_zalloc_arg() at uma_zalloc_arg+0x1036/frame 0xfffffe001fa7c840 malloc() at malloc+0xe1/frame 0xfffffe001fa7c8b0 tty_alloc_mutex() at tty_alloc_mutex+0x22c/frame 0xfffffe001fa7c8e0 pts_alloc() at pts_alloc+0x179/frame 0xfffffe001fa7c930 sys_posix_openpt() at sys_posix_openpt+0x94/frame 0xfffffe001fa7c970 ia32_syscall() at ia32_syscall+0x452/frame 0xfffffe001fa7cab0 int0x80_syscall_common() at int0x80_syscall_common+0x9c/frame 0xa KDB: enter: panic [ thread pid 788 tid 100119 ] Stopped at kdb_enter+0x6a: movq $0,kdb_why