mlpanic: kernel diagnostic assertion "ps->ps_uvncount == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_unveil.c", line 202
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 502144  44512      0     0x14000      0x200    1  reaper
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:212
__assert(ffffffff81faed3a,ffffffff81fb002c,ca,ffffffff81f6e7b1) at __assert+0x2e sys/kern/subr_prf.c:159
unveil_destroy(ffff800020b7c380) at unveil_destroy+0x1a9 sys/kern/kern_unveil.c:202
exit1(ffff800020b28c70,0,1) at exit1+0x38f sys/kern/kern_exit.c:218
sys_exit(ffff800020b28c70,ffff800021c15c90,ffff800021c15d00) at sys_exit+0x17 sys/kern/kern_exit.c:94
syscall(ffff800021c15d70) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800021c15d70) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,1,0,1,0,7f7ffffc3984) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffc3950, count: 7
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