TITLE: pool: free list modified: knotepl

panic: pool_do_get: knotepl free list modified: page 0xffffff0016069000; item addr 0xffffff00160699b8; offset 0x10=0x15c9ef10
Stopped at      db_enter+0xa:   popq    %rbp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*261118  11352      0           0  0x4000000    0  syz-executor1
db_enter() at db_enter+0xa
panic() at panic+0x147
pool_do_get(1,ffffffff81e8e708,0) at pool_do_get+0x3e9
pool_get(ffff80000e31f730,d) at pool_get+0x77
kqueue_register(4,16,ffff80000e44f1f8) at kqueue_register+0x2ab
sys_kevent(ffff80000e44f280,ffff80000e31f730,ffff80000e2ace90) at sys_kevent+0x
207
syscall(0) at syscall+0x3e4
Xsyscall_untramp(6,0,0,0,0,0) at Xsyscall_untramp+0xe4
end of kernel
end trace frame: 0x171c1a028b50, count: 7
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