panic: trap type 4, code=0, pc=ffffffff81d6af7b
Starting stack trace...
panic(ffffffff83046b64) at panic+0x1d0 sys/kern/subr_prf.c:229
kerntrap(ffff800030d62260) at kerntrap+0x29b sys/arch/amd64/amd64/trap.c:327
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
sys_semop(ffff80003c59fc10,ffff800030d62510,ffff800030d62460) at sys_semop+0x45b sys/kern/sysv_sem.c:615