panic: knote_enqueue:LINE: kq=ADDR kn=ADDR knote !QUEUED

Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported
kqueue: knote !QUEUED	syz			8	1739d	1776d
panic: knote_enqueue:1276: kq=0xfffffd806e7c0d68 kn=0xfffffd806eb54380 knote !QUEUED
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 328176  50068      0           0          0    1  syz-executor.1
* 45585  50068      0           0  0x4000000    0K syz-executor.1
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff8220dc07) at panic+0x15c sys/kern/subr_prf.c:207
kqueue_do_check(fffffd806e7c0d68,ffffffff82251644,4fc) at kqueue_do_check+0x232 sys/kern/kern_event.c:596
knote_enqueue(fffffd806eb54380) at knote_enqueue+0x80 sys/kern/kern_event.c:1277
kqueue_register(fffffd806e7c0d68,ffff800021bbafa0,ffff800020ac8780) at kqueue_register+0x820 sys/kern/kern_event.c:769
sys_kevent(ffff800020ac8780,ffff800021bbb168,ffff800021bbb1b0) at sys_kevent+0x2b6 sys/kern/kern_event.c:552
syscall(ffff800021bbb230) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800021bbb230) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd4bcd63e900, count: 7
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