panic: Bad entry start/end for new stack entry cpuid = 0 time = 1561512892 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe0016ae3370 vpanic() at vpanic+0x1e0/frame 0xfffffe0016ae33d0 panic() at panic+0x43/frame 0xfffffe0016ae3430 vm_map_stack_locked() at vm_map_stack_locked+0x364/frame 0xfffffe0016ae34a0 vm_map_stack() at vm_map_stack+0x11f/frame 0xfffffe0016ae3500 exec_new_vmspace() at exec_new_vmspace+0x4bd/frame 0xfffffe0016ae3570 exec_elf64_imgact() at exec_elf64_imgact+0x1262/frame 0xfffffe0016ae3670 kern_execve() at kern_execve+0x7d8/frame 0xfffffe0016ae39c0 start_init() at start_init+0x249/frame 0xfffffe0016ae3a60 fork_exit() at fork_exit+0xb0/frame 0xfffffe0016ae3ab0 fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0016ae3ab0 --- trap 0, rip = 0, rsp = 0, rbp = 0 --- KDB: enter: panic [ thread pid 1 tid 100002 ] Stopped at kdb_enter+0x6a: movq $0,kdb_why db> serialport: Connected to syzkaller.us-central1-c.ci-freebsd-main-test-1 port 1 (session ID: 6e2b3e8c2bbda2f2d75170c7973e1a4f10c1df267a5e84ade99eef10eccdc281, active connections: 1).