witness: thread 0xffff800020b5eee8 exiting with the following locks held:
exclusive rrwlock inode r = 0 (0xfffffd806635dc58)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  rw_enter+0x46d sys/kern/kern_rwlock.c:306
#2  rrw_enter+0x4f sys/kern/kern_rwlock.c:435
#3  VOP_LOCK+0x4b sys/kern/vfs_vops.c:602
#4  vn_rdwr+0x109 vn_lock sys/kern/vfs_vnops.c:561 [inline]
#4  vn_rdwr+0x109 sys/kern/vfs_vnops.c:317
#5  acct_process+0x5db sys/kern/kern_acct.c:221
#6  exit1+0x361 sys/kern/kern_exit.c:208
#7  sys_exit+0x17 sys/kern/kern_exit.c:94
#8  syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#8  syscall+0x552 sys/arch/amd64/amd64/trap.c:555
#9  Xsyscall+0x128
panic: thread 0xffff800020b5eee8 cannot exit while holding sleeplocks
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 464457  38288     73    0x100010          0    0  syslogd
*218288  50823      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:207
witness_thread_exit(ffff800020b5eee8) at witness_thread_exit+0x213 sys/kern/subr_witness.c:1364
reaper(ffff800020aff640) at reaper+0x14c sys/kern/kern_exit.c:423
end trace frame: 0x0, count: 11
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