[*] DF-0725 race: 12 children x 5000 rounds on gif666
[*] Expect: kernel panic (KKASSERT 'bit is already cleared'
     at if_clone_free_unit, or UAF/free-memory access)
[*] round 500/5000
[*] round 1000/5000
[*] round 1500/5000
[*] round 2000/5000
[*] round 2500/5000
[*] round 3000/5000
[*] round 3500/5000
[*] round 4000/5000
[*] round 4500/5000
[*] round 5000/5000
[+] completed 5000 rounds with no panic.
RACE_EXIT=0