panic: Assertion vm_object_busied((m->object)) failed at /usr/local-src/sys/vm/vm_page.c:5027
cpuid = 27
time = 1571148940
KDB: stack backtrace:
0xe0000000004278d0: at kdb_backtrace+0x60               (panic frame)
0xe0000000004279e0: at vpanic+0x1d8                     (panic frame)
0xe000000000427a90: at panic+0x40                       (panic frame)
0xe000000000427ac0: at vm_page_object_busy_assert+0x70  (vm_page_object_busy_assert)
0xe000000000427b30: at moea64_enter+0x7c                (moea64_enter)
0xe000000000427c00: at moea64_enter_object+0xc0         (moea64_enter_object)
0xe000000000427c60: at pmap_enter_object+0xac           (pmap_enter_object)
0xe000000000427cc0: at vm_map_try_merge_entries+0x6a0   (vm_map_pmap_enter)
0xe000000000427d70: at vm_map_insert+0x538              (vm_map_insert)
0xe000000000427e60: at vm_map_fixed+0x180               (vm_map_fixed) 
0xe000000000427f20: at elf64_stackgap+0x3ab8            (elf64_map_insert)
0xe000000000427ff0: at elf64_stackgap+0x3300            (elf64_load_sections)
0xe0000000004280f0: at elf64_stackgap+0x27fc            (exec_elf64_imgact)
0xe0000000004282a0: at kern_execve+0x614                (kern_execve)
0xe0000000004286e0: at mi_startup+0x1824                (start_init)
0xe000000000428820: at fork_exit+0xc4                   (fork_exit)
0xe0000000004288c0: at fork_trampoline+0x18             (fork_trampoline)
0xe0000000004288f0: at -0x4                             (stack frame 0)
KDB: enter: panic
[ thread pid 1 tid 100002 ]
Stopped at      kdb_enter+0x78: ori     r0, r0, 0x0
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