witness: lock order reversal: 1st 0xfffffd806bc58670 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd806dca6cc0 inode (&ip->i_lock) lock order [1] fdlock (&newfdp->fd_fd.fd_lock) -> [2] inode (&ip->i_lock) lock order data 0xffffffff83427432 -> 0xffffffff833a68ec is missing lock order [2] inode (&ip->i_lock) -> [3] sbufrcv (&so->so_rcv.sb_lock) #0 rw_do_enter_write+0xb7 sys/kern/kern_rwlock.c:233 #1 sblock+0xb7 sys/kern/uipc_socket2.c:536 #2 soreceive+0x28e sys/kern/uipc_socket.c:882 #3 fifo_read+0x11a sys/miscfs/fifofs/fifo_vnops.c:264 #4 VOP_READ+0x102 sys/kern/vfs_vops.c:227 #5 vn_rdwr+0x15b #6 vndsetcred+0xa1 sys/dev/vnd.c:684 #7 vndioctl+0xe6c sys/dev/vnd.c:485 #8 VOP_IOCTL+0xac sys/kern/vfs_vops.c:264 #9 vn_ioctl+0xf8 sys/kern/vfs_vnops.c:531 #10 sys_ioctl+0x5c3 #11 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #11 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #12 Xsyscall+0x128 lock order [3] sbufrcv (&so->so_rcv.sb_lock) -> [1] fdlock (&newfdp->fd_fd.fd_lock) #0 rw_do_enter_write+0xb7 sys/kern/kern_rwlock.c:233 #1 unp_externalize+0x3e4 sys/kern/uipc_usrreq.c:1070 #2 soreceive+0xc73 sys/kern/uipc_socket.c:1021 #3 recvit+0x40a sys/kern/uipc_syscalls.c:1072 #4 sys_recvmsg+0x1bf sys/kern/uipc_syscalls.c:872 #5 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #6 Xsyscall+0x128 Stopped at db_enter+0x25: addq $0x8,%rsp ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic the kernel did not panic ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 witness_checkorder(fffffd806dca6cc0,9,0) at witness_checkorder+0x1047 rw_do_enter_write(fffffd806dca6ca8,1) at rw_do_enter_write+0xb7 sys/kern/kern_rwlock.c:233 rrw_enter(fffffd806dca6ca8,1) at rrw_enter+0xc6 sys/kern/kern_rwlock.c:616 VOP_LOCK(fffffd806dca7b40,2001) at VOP_LOCK+0xa6 sys/kern/vfs_vops.c:524 vn_lock(fffffd806dca7b40,2001) at vn_lock+0xa4 sys/kern/vfs_vnops.c:570 vn_closefile(fffffd806be51738,ffff80003c0e2f90) at vn_closefile+0x111 vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806be51738,ffff80003c0e2f90) at vn_closefile+0x111 sys/kern/vfs_vnops.c:615 fdrop(fffffd806be51738,ffff80003c0e2f90) at fdrop+0x126 sys/kern/kern_descrip.c:1265 knote_drop(fffffd806a03a970,ffff80003c0e2f90) at knote_drop+0x1a1 sys/kern/kern_event.c:2142 knote_remove(ffff80003c0e2f90,fffffd806f0156c0,fffffd806f015748,4,0) at knote_remove+0x239 sys/kern/kern_event.c:2025 knote_fdclose(ffff80003c0e2f90,4) at knote_fdclose+0xf9 sys/kern/kern_event.c:2049 fdrelease(ffff80003c0e2f90,4) at fdrelease+0xf9 sys/kern/kern_descrip.c:749 syscall(ffff80003c5ea270) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c5ea270) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xd6b43fbeb0, count: -14 ddb{1}> show registers rdi 0 rsi 0x80000 acpi_pdirpa+0x6be71 rbp 0xffff80003c5e9d10 rbx 0xfffffd8004708938 rdx 0xffff80000144d640 rcx 0xffff80003c0e2f90 rax 0x7ffff acpi_pdirpa+0x6be70 r8 0xffff80003c5e9bf0 r9 0x8080808080808080 r10 0x5ce9f36d98d6151d r11 0xa7186588e7961e8 r12 0 r13 0xfffffd8003f20f00 r14 0x3 r15 0xffffffff rip 0xffffffff8136a795 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c5e9d00 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=470569 pid=82500 tcnt=2 stat=onproc flags process=10 proc=4000000 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000ffffc530,0xffffffff839933e8 process=0xffff8000ffff24e8 user=0xffff80003c5e5000, vmspace=0xfffffd806bca4908 estcpu=36, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 82500 42535 27981 0 2 0x10 syz-executor *82500 470569 27981 0 7 0x4000010 syz-executor 91077 149001 94093 0 2 0 syz-executor 91077 236365 94093 0 2 0x4000000 syz-executor 24482 366681 51334 0 3 0x3000 suspend syz-executor 24482 164139 51334 0 2 0x4081080 syz-executor 67150 48560 93793 0 2 0 syz-executor 67150 109794 93793 0 3 0x4000080 fifow syz-executor 67150 455522 93793 0 3 0x4000080 fsleep syz-executor 92332 308724 63391 0 3 0x80 nanoslp syz-executor 92332 132634 63391 0 3 0x4000080 fsleep syz-executor 92332 503015 63391 0 3 0x4000080 pipewr syz-executor 92332 200867 63391 0 3 0x4000080 fsleep syz-executor 71234 274530 0 0 3 0x14200 bored sosplice 59888 226684 0 0 3 0x14280 nfsidl nfsio 44744 324425 0 0 3 0x14280 nfsidl nfsio 75789 496389 0 0 3 0x14280 nfsidl nfsio 30794 347725 0 0 3 0x14280 nfsidl nfsio 48882 429979 0 0 3 0x14280 nfsidl nfsio 81142 269439 0 0 3 0x14280 nfsidl nfsio 41183 168252 0 0 3 0x14280 nfsidl nfsio 92148 295172 0 0 3 0x14280 nfsidl nfsio 35096 129205 0 0 3 0x14280 nfsidl nfsio 96797 490389 0 0 3 0x14280 nfsidl nfsio 53477 24046 0 0 3 0x14280 nfsidl nfsio 17382 497722 0 0 3 0x14280 nfsidl nfsio 79952 364735 0 0 3 0x14280 nfsidl nfsio 18696 107644 0 0 3 0x14280 nfsidl nfsio 9929 326135 0 0 3 0x14280 nfsidl nfsio 28346 5354 0 0 3 0x14280 nfsidl nfsio 92278 454414 0 0 3 0x14280 nfsidl nfsio 86631 232727 0 0 3 0x14280 nfsidl nfsio 26677 146160 0 0 3 0x14280 nfsidl nfsio 97845 21676 0 0 3 0x14280 nfsidl nfsio 86783 309433 57710 0 3 0x82 sbwait sshd-session 94093 46828 80333 0 3 0x82 nanoslp syz-executor 27981 138381 80333 0 3 0x82 nanoslp syz-executor 59626 179464 80333 0 3 0x82 nanoslp syz-executor 93793 419948 80333 0 2 0x482 syz-executor 63391 14116 80333 0 3 0x82 nanoslp syz-executor 51334 346594 80333 0 3 0x82 nanoslp syz-executor 18325 270147 80333 0 3 0x82 nanoslp syz-executor 95371 16216 80333 0 3 0x82 nanoslp syz-executor 80333 107877 76954 0 3 0x82 kqread syz-executor 76954 376590 81866 0 3 0x10008a sigsusp ksh 81866 79310 99568 0 3 0x98 kqread sshd-session 99568 95691 57710 0 3 0x92 kqread sshd-session 19280 333489 1 0 3 0x100083 ttyopn getty 57710 175797 1 0 3 0x88 kqread sshd 96278 403152 82783 74 3 0x1100092 bpf pflogd 82783 282573 1 0 3 0x80 sbwait pflogd 30284 145946 16019 73 3 0x1100090 kqread syslogd 16019 383640 1 0 3 0x100082 sbwait syslogd 66882 516497 1 0 3 0x100080 kqread resolvd 92504 193599 61704 77 3 0x100092 kqread dhcpleased 13321 374586 61704 77 3 0x100092 kqread dhcpleased 61704 414168 1 0 3 0x80 kqread dhcpleased 22287 94726 0 0 3 0x14200 bored smr 92988 69439 0 0 2 0x14200 zerothread 70917 235960 0 0 3 0x14200 aiodoned aiodoned 67999 174467 0 0 3 0x14200 syncer update 20030 34453 0 0 3 0x14200 cleaner cleaner 38143 437236 0 0 7 0x14200 reaper 38538 63443 0 0 3 0x14200 pgdaemon pagedaemon 91442 348528 0 0 3 0x14200 bored viomb 3539 464374 0 0 3 0x40014200 acpi0 acpi0 91455 123072 0 0 3 0x40014200 idle1 16886 43949 0 0 3 0x14200 bored softnet3 41474 500613 0 0 3 0x14200 bored softnet2 88810 380958 0 0 3 0x14200 bored softnet1 72984 171019 0 0 2 0x14200 softnet0 52865 152372 0 0 3 0x14200 bored systqmp 7024 301492 0 0 3 0x14200 bored systq 25617 169363 0 0 3 0x14200 tmoslp softclockmp 42916 501417 0 0 2 0x40014200 softclock 57535 421388 0 0 3 0x40014200 idle0 1 5503 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 82500 (syz-executor) thread 0xffff80003c0e2f90 (470569) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8398f708) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 vn_closefile+0x41 sys/kern/vfs_vnops.c:608 #2 fdrop+0x126 sys/kern/kern_descrip.c:1265 #3 knote_drop+0x1a1 sys/kern/kern_event.c:2142 #4 knote_remove+0x239 sys/kern/kern_event.c:2025 #5 knote_fdclose+0xf9 sys/kern/kern_event.c:2049 #6 fdrelease+0xf9 sys/kern/kern_descrip.c:749 #7 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #7 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #8 Xsyscall+0x128 exclusive rwlock fdlock r = 0 (0xfffffd806bc58670) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 rw_do_enter_write+0x3ea sys/kern/kern_rwlock.c:316 #2 sys_close+0xc4 sys/kern/kern_descrip.c:767 #3 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #3 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #4 Xsyscall+0x128 Process 91077 (syz-executor) thread 0xffff80003c0e27e0 (236365) exclusive rrwlock inode r = 0 (0xfffffd806bbf4dc0) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 rw_do_enter_write+0x3ea sys/kern/kern_rwlock.c:316 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:616 #3 VOP_LOCK+0xa6 sys/kern/vfs_vops.c:524 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x190 sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x23c sys/kern/sys_generic.c:380 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #9 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10205 11092K 11511K 166960K 12365 0 pcb 17 14K 15K 166960K 118 0 rtable 236 10K 10K 166960K 431 0 pf 39 18K 25K 166960K 119 0 ifaddr 41 7K 8K 166960K 74 0 ifgroup 55 2K 2K 166960K 115 0 sysctl 4 1K 1K 166960K 4 0 counters 64 36K 37K 166960K 254 0 ioctlops 0 0K 4K 166960K 1622 0 iov 0 0K 18K 166960K 42 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1406 88K 89K 166960K 1999 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 23 0 VM map 2 1K 1K 166960K 2 0 sem 20 5K 5K 166960K 52 0 dirhash 12 2K 2K 166960K 30 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 16 57K 240K 166960K 789 0 sigio 0 0K 0K 166960K 14 0 proc 73 91K 128K 166960K 593 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 229 0 in_multi 92 6K 7K 166960K 124 0 ether_multi 1 0K 0K 166960K 3 0 mrt 0 0K 0K 166960K 3 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 79 360K 360K 166960K 79 0 exec 0 0K 1K 166960K 582 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 240 73K 87K 166960K 8963 0 UVM aobj 30 2K 2K 166960K 31 0 pinsyscall 43 86K 106K 166960K 1902 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 26 0 NDP 12 0K 2K 166960K 50 0 temp 62 8640K 8893K 166960K 15962 0 kqueue 14 22K 30K 166960K 143 0 SYN cache 2 16K 16K 166960K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 24 0 0 1 0 1 1 0 8 0 rtpcb 120 83 0 80 1 0 1 1 0 8 0 rtentry 112 121 0 17 4 0 4 4 0 8 0 unpcb 144 455 0 436 3 1 2 2 0 8 1 syncache 336 7 0 7 2 1 1 1 0 8 1 tcpqe 32 2 0 2 1 0 1 1 0 8 1 tcpcb 808 174 0 166 5 3 2 4 0 8 1 arp 120 19 0 3 1 0 1 1 0 8 0 inpcb 376 656 0 644 9 3 6 6 0 8 4 nd6 136 26 0 3 1 0 1 1 0 8 0 pkpcb 40 3 0 3 1 1 0 1 0 8 0 kcovpl 48 8 0 0 1 0 1 1 0 8 0 mppekey 1024 2 0 2 1 1 0 1 0 8 0 ppxss 1168 89 0 89 2 1 1 1 0 8 1 pppxif 1472 3 0 3 2 2 0 1 0 8 0 pffrag 232 3 0 0 1 0 1 1 0 482 0 pffrnode 88 2 0 0 1 0 1 1 0 8 0 pffrent 40 4 0 1 1 0 1 1 0 8 0 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pftag 88 2 0 0 1 0 1 1 0 8 0 pfstitem 24 61 0 12 1 0 1 1 0 8 0 pfstkey 128 62 0 13 2 0 2 2 0 8 0 pfstate 376 62 0 13 6 0 6 6 0 8 0 pfrule 1344 29 0 23 2 1 1 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 482 0 64 29 1 28 29 0 8 0 art_table 32 484 0 64 4 0 4 4 0 8 0 art_node 16 120 0 26 1 0 1 1 0 8 0 sysvmsgpl 40 11 0 8 2 1 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 47 0 29 1 0 1 1 0 8 0 shmpl 112 28 0 1 1 0 1 1 0 8 0 dirhash 1024 29 0 12 3 0 3 3 0 8 0 dino2pl 256 2759 0 1249 95 0 95 95 0 8 0 ffsino 280 2759 0 1249 109 0 109 109 0 8 0 nchpl 144 3835 0 2141 63 0 63 63 0 8 0 rtmask 32 5 0 5 1 0 1 1 0 8 1 uvmvnodes 80 3257 0 0 67 0 67 67 0 8 0 vnodes 216 3257 0 0 181 0 181 181 0 8 0 namei 1024 13200 0 13200 2 1 1 1 0 8 1 percpumem 16 141 0 95 1 0 1 1 0 8 0 kstatmem 264 68 0 44 3 0 3 3 0 8 1 scsiplug 72 4 0 4 2 2 0 1 0 8 0 scxspl 216 12104 0 12104 10 2 8 8 1 8 8 plimitpl 152 133 0 115 1 0 1 1 0 8 0 sigapl 424 1109 0 1037 9 0 9 9 0 8 0 futexpl 64 10193 0 10189 1 0 1 1 0 8 0 knotepl 120 551 0 0 17 0 17 17 0 8 0 kqueuepl 216 259 0 247 3 0 3 3 0 8 2 pipepl 328 176 0 147 3 0 3 3 0 8 0 fdescpl 504 1069 0 1038 6 1 5 6 0 8 0 filepl 152 6141 0 5914 15 3 12 13 0 8 2 lockfpl 104 243 0 241 1 0 1 1 0 8 0 lockfspl 48 93 0 91 1 0 1 1 0 8 0 sessionpl 144 25 0 15 1 0 1 1 0 8 0 pgrppl 48 47 0 29 1 0 1 1 0 8 0 ucredpl 104 870 0 854 1 0 1 1 0 8 0 zombiepl 144 1040 0 1037 1 0 1 1 0 8 0 processpl 1176 1109 0 1037 6 0 6 6 0 8 0 procpl 656 2262 0 2181 9 1 8 8 0 8 0 srpgc 96 2 0 2 1 1 0 1 0 8 0 sosppl 168 2 0 2 1 0 1 1 0 8 1 sockpl 688 1204 0 1170 10 2 8 8 0 8 4 mcl64k 65536 2 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 130 0 0 17 0 17 17 0 8 0 mcl2k 2048 23 0 0 3 0 3 3 0 8 0 mtagpl 96 42 0 0 2 0 2 2 0 8 0 mbufpl 256 226 0 0 15 0 15 15 0 8 0 bufpl 280 3493 0 132 241 0 241 241 0 8 0 anonpl 24 152264 0 148199 54 4 50 50 0 184 22 amapchunkpl 152 29449 0 28921 38 3 35 36 0 158 12 amappl16 200 2666 0 2620 23 12 11 15 0 8 7 amappl15 192 4 0 4 1 1 0 1 0 8 0 amappl14 184 119 0 105 1 0 1 1 0 8 0 amappl13 176 2 0 2 2 2 0 1 0 8 0 amappl12 168 1728 0 1696 3 1 2 2 0 8 0 amappl11 160 50 0 34 1 0 1 1 0 8 0 amappl10 152 4 0 3 1 0 1 1 0 8 0 amappl9 144 278 0 278 1 1 0 1 0 8 0 amappl8 136 24 0 21 1 0 1 1 0 8 0 amappl7 128 113 0 100 1 0 1 1 0 8 0 amappl6 120 177 0 173 1 0 1 1 0 8 0 amappl5 112 144 0 134 1 0 1 1 0 8 0 amappl4 104 349 0 328 1 0 1 1 0 8 0 amappl3 96 5676 0 5556 4 0 4 4 0 8 0 amappl2 88 689 0 621 2 0 2 2 0 8 0 amappl1 80 10479 0 9821 17 1 16 16 0 8 0 amappl 88 8526 0 8347 5 0 5 5 0 92 0 dma4096 4096 2 0 2 2 1 1 1 0 8 1 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 254 0 254 2 2 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 19 0 18 1 0 1 1 0 8 0 aobjpl 72 30 0 1 1 0 1 1 0 8 0 uaddrrnd 24 1069 0 1037 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1069 0 1037 1 0 1 1 0 8 0 vmmpekpl 168 10488 0 10441 3 0 3 3 0 8 0 vmmpepl 168 70145 0 68114 101 3 98 100 0 357 6 vmsppl 456 1068 0 1037 5 0 5 5 0 8 0 rwobjpl 64 23951 0 19603 71 0 71 71 0 8 0 pdppl 4096 2146 0 2074 114 39 75 88 0 8 3 pvpl 32 15826 0 0 129 1 128 128 0 265 0 pmappl 248 1068 0 1037 3 0 3 3 0 8 0 extentpl 40 55 0 38 1 0 1 1 0 8 0 phpool 112 303 0 50 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff837e4ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_lock(ffffffff8398f500) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff8398f500) at __mp_lock+0x199 sys/kern/kern_lock.c:144 softintr_dispatch(0) at softintr_dispatch+0x5b sys/arch/amd64/amd64/softintr.c:88 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8398f500) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff8398f500) at __mp_lock+0x192 sys/kern/kern_lock.c:144 reaper(ffff80002a3091f8) at reaper+0x24b sys/kern/kern_exit.c:481 end trace frame: 0x0, count: -8 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x25: addq $0x8,%rsp ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 witness_checkorder(fffffd806dca6cc0,9,0) at witness_checkorder+0x1047 rw_do_enter_write(fffffd806dca6ca8,1) at rw_do_enter_write+0xb7 sys/kern/kern_rwlock.c:233 rrw_enter(fffffd806dca6ca8,1) at rrw_enter+0xc6 sys/kern/kern_rwlock.c:616 VOP_LOCK(fffffd806dca7b40,2001) at VOP_LOCK+0xa6 sys/kern/vfs_vops.c:524 vn_lock(fffffd806dca7b40,2001) at vn_lock+0xa4 sys/kern/vfs_vnops.c:570 vn_closefile(fffffd806be51738,ffff80003c0e2f90) at vn_closefile+0x111 vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806be51738,ffff80003c0e2f90) at vn_closefile+0x111 sys/kern/vfs_vnops.c:615 fdrop(fffffd806be51738,ffff80003c0e2f90) at fdrop+0x126 sys/kern/kern_descrip.c:1265 knote_drop(fffffd806a03a970,ffff80003c0e2f90) at knote_drop+0x1a1 sys/kern/kern_event.c:2142 knote_remove(ffff80003c0e2f90,fffffd806f0156c0,fffffd806f015748,4,0) at knote_remove+0x239 sys/kern/kern_event.c:2025 knote_fdclose(ffff80003c0e2f90,4) at knote_fdclose+0xf9 sys/kern/kern_event.c:2049 fdrelease(ffff80003c0e2f90,4) at fdrelease+0xf9 sys/kern/kern_descrip.c:749 syscall(ffff80003c5ea270) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c5ea270) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xd6b43fbeb0, count: -14