panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 953
Stopped at      db_enter+37:    addq    $8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
  15468  66023      0         0x2          0    0  syz-executor
db_enter() at db_enter+37
panic(ffffffff833956d0) at panic+485
__assert(ffffffff833d22f8,ffffffff833dddd1,3b9,ffffffff83407984) at __assert+41
refcnt_finalize(ffff80002abeaf20,ffffffff8338dd6f) at refcnt_finalize+475
pppx_if_destroy(285b9a,ffff80002abeaf18) at pppx_if_destroy+61
pppxclose(285b9a,41,2000,ffff80002a270d10) at pppxclose+160
spec_close(ffff80002a36ea90) at spec_close+1047
VOP_CLOSE(fffffd8069cbfd80,41,fffffd80097fb4e0,ffff80002a270d10) at VOP_CLOSE+306
vn_closefile(fffffd8068302810,ffff80002a270d10) at vn_closefile+299
fdrop(fffffd8068302810,ffff80002a270d10) at fdrop+289
closef(fffffd8068302810,ffff80002a270d10) at closef+402
fdfree(ffff80002a270d10) at fdfree+278
exit1(ffff80002a270d10,0,0,1) at exit1+1398
sys_exit(ffff80002a270d10,ffff80002a36ee00,ffff80002a36ed50) at sys_exit+26
end trace frame: 0xffff80002a36edf0, count: 0
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