panic: kernel diagnostic assertion "ps->ps_uvncount == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_unveil.c", line 188
Stopped at      db_enter+0x1c:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
  74600  93076      0           0          0    0  syz-executor.4
db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff827a340e) at panic+0x17b sys/kern/subr_prf.c:198
__assert(ffffffff8281e70b,ffffffff82820902,bc,ffffffff827b65e4) at __assert+0x29 sys/kern/subr_prf.c:157
unveil_destroy(ffff80002130a5c8) at unveil_destroy+0x1a4 sys/kern/kern_unveil.c:188
exit1(ffff8000212bf5f0,0,0,3) at exit1+0x3d5 sys/kern/kern_exit.c:220
single_thread_check_locked(ffff8000212bf5f0,0,0) at single_thread_check_locked+0x237 sys/kern/kern_sig.c:2015
userret(ffff8000212bf5f0) at userret+0x7c single_thread_check sys/kern/kern_sig.c:2054 [inline]
userret(ffff8000212bf5f0) at userret+0x7c sys/kern/kern_sig.c:1970
intr_user_exit() at intr_user_exit+0x3c
end of kernel
end trace frame: 0x76f602a27660, count: 7
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