witness: lock order reversal:
 1st 0xffff8000110bcac0 sbufsnd (&so->so_snd.sb_lock)
 2nd 0xffff800001d16ee8 inode (&ip->i_lock)
lock order [1] sbufsnd (&so->so_snd.sb_lock) -> [2] inode (&ip->i_lock)
lock order data 0xffffffff84a56a20 -> 0xffffffff8469cc40 is missing
lock order [2] inode (&ip->i_lock) -> [3] sbufrcv (&so->so_rcv.sb_lock)
#0  rw_do_enter_write+0xc4 sys/kern/kern_rwlock.c:234
#1  sblock+0xbf sys/kern/uipc_socket2.c:536
#2  soreceive+0x3b1 sys/kern/uipc_socket.c:890
#3  fifo_read+0x1d9 sys/miscfs/fifofs/fifo_vnops.c:264
#4  VOP_READ+0x1a8 sys/kern/vfs_vops.c:227
#5  vn_rdwr+0x1bc sys/kern/vfs_vnops.c:-1
#6  vndsetcred+0xbf sys/dev/vnd.c:685
#7  vndioctl+0x12ef sys/dev/vnd.c:486
#8  VOP_IOCTL+0x131 sys/kern/vfs_vops.c:264
#9  vn_ioctl+0x18c sys/kern/vfs_vnops.c:537
#10 sys_ioctl+0x868 sys/kern/sys_generic.c:510
#11 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#11 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
#12 Xsyscall+0x128
lock order [3] sbufrcv (&so->so_rcv.sb_lock) -> [1] sbufsnd (&so->so_snd.sb_lock)
#0  rw_do_enter_write+0xc4 sys/kern/kern_rwlock.c:234
#1  sblock+0xbf sys/kern/uipc_socket2.c:536
#2  sosplice+0x4a5 sys/kern/uipc_socket.c:1352
#3  sosetopt+0xdac sys/kern/uipc_socket.c:-1
#4  sys_setsockopt+0x466 sys/kern/uipc_syscalls.c:1234
#5  syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#5  syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
#6  Xsyscall+0x128
Stopped at      db_enter+0x17:  popq    %rbp
ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
the kernel did not panic
ddb{1}> show kasan
kasan: no report recorded this boot
ddb{1}> trace
db_enter() at db_enter+0x17 sys/arch/amd64/amd64/db_interface.c:457
witness_checkorder(ffff800001d16ee8,9,0) at witness_checkorder+0x19db sys/kern/subr_witness.c:-1
rw_do_enter_write(ffff800001d16ed0,1) at rw_do_enter_write+0xc4 sys/kern/kern_rwlock.c:234
rrw_enter(ffff800001d16ed0,1) at rrw_enter+0xf0 sys/kern/kern_rwlock.c:621
VOP_LOCK(ffff800001bdf6c8,2001) at VOP_LOCK+0x17e sys/kern/vfs_vops.c:527
vn_lock(ffff800001bdf6c8,2001) at vn_lock+0xca sys/kern/vfs_vnops.c:576
vfs_lookup(ffff8000299ea760) at vfs_lookup+0x1f7 sys/kern/vfs_lookup.c:431
namei(ffff8000299ea760) at namei+0xe19 sys/kern/vfs_lookup.c:250
unp_connect(ffff8000110bc8d8,fffffd8011b34100,ffff800039b1e558) at unp_connect+0x2b9 sys/kern/uipc_usrreq.c:875
uipc_dgram_send(ffff8000110bc8d8,fffffd805d55a500,fffffd8011b34100,0) at uipc_dgram_send+0x1f8 sys/kern/uipc_usrreq.c:609
sosend(ffff8000110bc8d8,fffffd8011b34100,ffff8000299eab00,0,0,400) at sosend+0xb96 sys/kern/uipc_socket.c:-1
sendit(ffff800039b1e558,3,ffff8000299eac10,400,ffff8000299eade0) at sendit+0x83b sys/kern/uipc_syscalls.c:785
sys_sendto(ffff800039b1e558,ffff8000299eae80,ffff8000299eade0) at sys_sendto+0x15c sys/kern/uipc_syscalls.c:563
syscall(ffff8000299eae80) at syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff8000299eae80) at syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xce26ffe3150, count: -15
ddb{1}> show registers
rdi                                0
rsi                                0
rbp               0xffff8000299ea0c0
rbx               0xffffffff84a56a60    .str.9
rdx                                0
rcx               0xffff800028fe3ff0
rax                                0
r8                0xffff8000299e9ea0
r9                0xffff8000299e9e40
r10                                0
r11               0xffffffff81598630