kernel: protection fault trap, code=0 Stopped at witness_checkorder+0x1ec: movl 0x8(%r14),%ebx ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic the kernel did not panic ddb{1}> trace witness_checkorder(fffffd806f125e68,9,0) at witness_checkorder+0x1ec sys/kern/subr_witness.c:794 mtx_enter(fffffd806f125e58) at mtx_enter+0x3e sys/kern/kern_lock.c:265 knote_remove(ffff800022d062b0,fffffd806f125e58,fffffd806f125ee0,3,0) at knote_remove+0x20d sys/kern/kern_event.c:1881 knote_fdclose(ffff800022d062b0,3) at knote_fdclose+0xae sys/kern/kern_event.c:1934 fdfree(ffff800022d062b0) at fdfree+0xdf sys/kern/kern_descrip.c:1196 exit1(ffff800022d062b0,0,0,1) at exit1+0x3e4 sys/kern/kern_exit.c:206 sys_exit(ffff800022d062b0,ffff80002615bab0,ffff80002615bb00) at sys_exit+0x1a sys/kern/kern_exit.c:89 syscall(ffff80002615bb80) at syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff80002615bb80) at syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6fe4b2c565d0, count: -9 ddb{1}> show registers rdi 0 rsi 0x20000 acpi_pdirpa+0xbe63 rbp 0xffff80002615b850 rbx 0xe rdx 0 rcx 0xffff800022d062b0 rax 0xffff800020d58ff0 r8 0x1 r9 0x1 r10 0x4fd76606c193eb34 r11 0xa518b5e505c61aa5 r12 0 r13 0xfffffd806f125e68 r14 0x3ff5555555555555 r15 0xffff800022d062b0 rip 0xffffffff8146926c witness_checkorder+0x1ec cs 0x8 rflags 0x10246 __ALIGN_SIZE+0xf246 rsp 0xffff80002615b7a0 ss 0x10 witness_checkorder+0x1ec: movl 0x8(%r14),%ebx ddb{1}> show proc PROC (syz-executor.1) pid=354034 stat=onproc flags process=1018 proc=2000 pri=0, usrpri=77, nice=20 forw=0xffffffffffffffff, list=0xffff8000212792b8,0xffff800022d06d60 process=0xffff8000ffff4018 user=0xffff800026156000, vmspace=0xfffffd8065426598 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 42235 284866 75434 32767 2 0x10 syz-executor.5 19837 28135 71022 32767 2 0x10 syz-executor.0 19837 239222 71022 32767 3 0x4000090 fsleep syz-executor.0 98625 518886 60982 32767 2 0x10 syz-executor.3 98625 377454 60982 32767 3 0x4000090 fsleep syz-executor.3 88535 355538 52742 32767 3 0x10 biowait syz-executor.2 52742 359919 68952 0 3 0x82 wait syz-executor.2 75228 374786 38996 32767 3 0x10 biowait syz-executor.6 38996 463312 68952 0 3 0x82 wait syz-executor.6 19096 18984 48699 32767 3 0x10 getblk syz-executor.7 48699 242990 68952 0 3 0x82 wait syz-executor.7 60982 247956 12162 32767 3 0x90 nanoslp syz-executor.3 12162 317804 68952 0 3 0x82 wait syz-executor.3 76628 54817 91318 32767 7 0x10 syz-executor.4 91318 503048 68952 0 3 0x82 wait syz-executor.4 88321 136694 0 0 3 0x14200 bored sosplice 75434 337792 31854 32767 3 0x90 nanoslp syz-executor.5 31854 370417 68952 0 3 0x82 wait syz-executor.5 33623 253829 46337 32767 3 0x90 nanoslp syz-executor.1 46337 262231 68952 0 3 0x82 wait syz-executor.1 71022 359094 6914 32767 3 0x90 nanoslp syz-executor.0 6914 283675 68952 0 3 0x82 wait syz-executor.0 68952 22912 87414 0 3 0x2000082 thrsleep syz-fuzzer 68952 108525 87414 0 3 0x6000082 thrsleep syz-fuzzer 68952 67642 87414 0 3 0x6000082 thrsleep syz-fuzzer 68952 424819 87414 0 3 0x6000082 wait syz-fuzzer 68952 183960 87414 0 3 0x6000082 thrsleep syz-fuzzer 68952 202451 87414 0 3 0x6000082 wait syz-fuzzer 68952 233436 87414 0 3 0x6000082 kqread syz-fuzzer 68952 116625 87414 0 3 0x6000082 wait syz-fuzzer 68952 270738 87414 0 3 0x6000082 wait syz-fuzzer 68952 57628 87414 0 3 0x6000082 thrsleep syz-fuzzer 68952 220961 87414 0 3 0x6000082 wait syz-fuzzer 68952 134700 87414 0 3 0x6000082 thrsleep syz-fuzzer 68952 63145 87414 0 3 0x6000082 wait syz-fuzzer 68952 425590 87414 0 3 0x6000082 wait syz-fuzzer 68952 113906 87414 0 3 0x6000082 thrsleep syz-fuzzer 68952 394805 87414 0 3 0x6000082 wait syz-fuzzer 87414 163441 33168 0 3 0x10008a sigsusp ksh 33168 169338 61962 0 3 0x9a kqread sshd 48026 198614 1 0 3 0x100083 ttyin getty 61962 125587 1 0 3 0x88 kqread sshd 40193 310687 58642 73 3 0x1100090 kqread syslogd 58642 212555 1 0 3 0x100082 netio syslogd 7882 520073 1 0 3 0x100080 kqread resolvd 14918 385921 58510 77 3 0x100092 kqread dhcpleased 88881 52946 58510 77 3 0x100092 kqread dhcpleased 58510 415833 1 0 3 0x80 kqread dhcpleased 78773 25931 0 0 3 0x14200 bored smr 59215 122347 0 0 2 0x14200 zerothread 55738 159774 0 0 3 0x14200 aiodoned aiodoned 97276 361705 0 0 3 0x14200 syncer update 61953 475352 0 0 3 0x14200 cleaner cleaner 79721 279198 0 0 2 0x14200 reaper 75838 350062 0 0 3 0x14200 pgdaemon pagedaemon 24418 59903 0 0 3 0x14200 bored viomb 72389 521350 0 0 3 0x40014200 acpi0 acpi0 66065 153614 0 0 3 0x40014200 idle1 88063 448874 0 0 3 0x14200 bored softnet3 8639 285587 0 0 3 0x14200 bored softnet2 63426 424542 0 0 3 0x14200 bored softnet1 18502 84466 0 0 3 0x14200 bored softnet0 60710 190896 0 0 3 0x14200 bored systqmp 90469 29968 0 0 3 0x14200 bored systq 19613 235897 0 0 3 0x40014200 bored softclock 40505 213525 0 0 3 0x40014200 idle0 1 464780 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 88535 (syz-executor.2) thread 0xffff8000212782c8 (355538) exclusive rrwlock inode r = 0 (0xfffffd80671dd1b0) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vget+0x200 sys/kern/vfs_subr.c:676 #6 ufs_ihashget+0x121 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x7c sys/ufs/ffs/ffs_vfsops.c:1314 #8 ufs_lookup+0x13ba sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5c sys/kern/vfs_vops.c:85 #10 vfs_lookup+0x6e2 sys/kern/vfs_lookup.c:566 #11 namei+0x55a sys/kern/vfs_lookup.c:250 #12 dounlinkat+0x9d sys/kern/vfs_syscalls.c:1847 #13 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #13 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806ceaf4e8) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vfs_lookup+0xd5 sys/kern/vfs_lookup.c:418 #6 namei+0x55a sys/kern/vfs_lookup.c:250 #7 dounlinkat+0x9d sys/kern/vfs_syscalls.c:1847 #8 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #8 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #9 Xsyscall+0x128 Process 75228 (syz-executor.6) thread 0xffff8000212dc550 (374786) exclusive rrwlock inode r = 0 (0xfffffd806ceaf5f8) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vget+0x200 sys/kern/vfs_subr.c:676 #6 ufs_ihashget+0x121 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x7c sys/ufs/ffs/ffs_vfsops.c:1314 #8 ufs_lookup+0x13ba sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5c sys/kern/vfs_vops.c:85 #10 vfs_lookup+0x6e2 sys/kern/vfs_lookup.c:566 #11 namei+0x55a sys/kern/vfs_lookup.c:250 #12 dounlinkat+0x9d sys/kern/vfs_syscalls.c:1847 #13 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #13 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd80671ddc50) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vfs_lookup+0xd5 sys/kern/vfs_lookup.c:418 #6 namei+0x55a sys/kern/vfs_lookup.c:250 #7 dounlinkat+0x9d sys/kern/vfs_syscalls.c:1847 #8 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #8 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #9 Xsyscall+0x128 Process 19096 (syz-executor.7) thread 0xffff800022d06800 (18984) exclusive rrwlock inode r = 0 (0xfffffd8060fe71a8) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 ufs_ihashins+0x46 sys/ufs/ufs/ufs_ihash.c:140 #5 ffs_vget+0x141 sys/ufs/ffs/ffs_vfsops.c:1343 #6 ffs_inode_alloc+0x1c2 sys/ufs/ffs/ffs_alloc.c:394 #7 ufs_mkdir+0xf8 sys/ufs/ufs/ufs_vnops.c:1149 #8 VOP_MKDIR+0xc3 sys/kern/vfs_vops.c:388 #9 domkdirat+0x125 sys/kern/vfs_syscalls.c:3073 #10 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #10 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #11 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd8060fe74d8) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vfs_lookup+0xd5 sys/kern/vfs_lookup.c:418 #6 namei+0x55a sys/kern/vfs_lookup.c:250 #7 domkdirat+0x79 sys/kern/vfs_syscalls.c:3058 #8 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #8 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #9 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10203 6411K 6420K 78643K 11309 0 pcb 13 16K 18K 78643K 19 0 rtable 236 6K 7K 78643K 712 0 pf 29 8K 8K 78643K 47 0 ifaddr 44 15K 15K 78643K 84 0 ifgroup 50 2K 2K 78643K 86 0 sysctl 2 0K 0K 78643K 2 0 counters 60 35K 35K 78643K 78 0 ioctlops 0 0K 2K 78643K 115 0 iov 0 0K 24K 78643K 404 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1278 80K 80K 78643K 1816 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 42 0 VM map 2 1K 1K 78643K 2 0 sem 10 1K 1K 78643K 10 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 22 81K 121K 78643K 2910 0 sigio 0 0K 0K 78643K 93 0 proc 56 78K 103K 78643K 905 0 subproc 104 6K 6K 78643K 221 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 360 0 in_multi 99 7K 7K 78643K 230 0 ether_multi 1 0K 0K 78643K 3 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 157 705K 705K 78643K 157 0 exec 0 0K 1K 78643K 707 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 8 62K 64K 78643K 10 0 UVM amap 357 89K 95K 78643K 30371 0 UVM aobj 131 4K 4K 78643K 143 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 133 0 NDP 11 0K 2K 78643K 54 0 temp 74 5920K 6000K 78643K 10949 0 kqueue 12 18K 26K 78643K 189 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 22 0 0 1 0 1 1 0 8 0 rtpcb 120 89 0 86 1 0 1 1 0 8 0 rtentry 112 214 0 103 4 0 4 4 0 8 0 unpcb 144 1777 0 1764 16 13 3 6 0 8 2 syncache 304 45 0 45 5 4 1 1 0 8 1 tcpqe 32 163 0 163 7 6 1 1 0 8 1 tcpcb 808 4748 0 4728 59 49 10 20 0 8 7 arp 120 36 0 18 1 0 1 1 0 8 0 ipq 40 2 0 2 1 1 0 1 0 8 0 ipqe 40 12 0 12 1 1 0 1 0 8 0 inpcb 368 7845 0 7818 85 76 9 20 0 8 3 nd6 136 55 0 30 1 0 1 1 0 8 0 kcovpl 48 17 0 9 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 863 0 405 29 0 29 29 0 8 0 art_table 32 864 0 405 4 0 4 4 0 8 0 art_node 16 213 0 112 1 0 1 1 0 8 0 sysvmsgpl 40 8 0 0 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 8 0 0 1 0 1 1 0 8 0 shmpl 112 140 0 12 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 5011 0 3567 91 0 91 91 0 8 0 ffsino 272 5011 0 3567 97 0 97 97 0 8 0 nchpl 144 8863 0 7223 63 0 63 63 0 8 0 uvmvnodes 80 5241 0 0 107 0 107 107 0 8 0 vnodes 216 5241 0 0 292 0 292 292 0 8 0 namei 1024 29448 0 29447 3 2 1 2 0 8 0 percpumem 16 52 0 9 1 0 1 1 0 8 0 kstatmem 264 40 0 18 2 0 2 2 0 8 0 scxspl 216 26563 0 26555 17 16 1 8 1 8 0 plimitpl 152 447 0 424 3 2 1 2 0 8 0 sigapl 424 3178 0 3127 7 0 7 7 0 8 0 futexpl 64 24669 0 24667 1 0 1 1 0 8 0 knotepl 120 335 0 0 11 0 11 11 0 8 0 kqueuepl 216 951 0 941 21 18 3 8 0 8 2 pipepl 320 392 0 364 6 3 3 6 0 8 0 fdescpl 496 3160 0 3127 7 2 5 6 0 8 0 filepl 152 22219 0 21978 27 13 14 22 0 8 4 lockfpl 104 365 0 363 1 0 1 1 0 8 0 lockfspl 48 125 0 123 1 0 1 1 0 8 0 sessionpl 144 32 0 16 1 0 1 1 0 8 0 pgrppl 48 418 0 402 1 0 1 1 0 8 0 ucredpl 104 2607 0 2589 1 0 1 1 0 8 0 zombiepl 144 3128 0 3127 1 0 1 1 0 8 0 processpl 1072 3178 0 3127 5 1 4 5 0 8 0 procpl 680 8222 0 8153 10 2 8 8 0 8 1 sosppl 168 39 0 38 1 0 1 1 0 8 0 sockpl 488 9755 0 9712 181 166 15 29 0 8 8 mcl64k 65536 17 0 0 3 0 3 3 0 8 0 mcl16k 16384 14 0 0 2 0 2 2 0 8 0 mcl12k 12288 9 0 0 1 0 1 1 0 8 0 mcl9k 9216 12 0 0 1 0 1 1 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 25 0 0 3 0 3 3 0 8 0 mcl2k2 2112 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 282 0 0 36 0 36 36 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 1280 0 0 76 0 76 76 0 8 0 bufpl 288 8276 0 1950 452 0 452 452 0 8 0 anonpl 24 468104 0 457380 114 42 72 94 0 186 0 amapchunkpl 152 96944 0 96099 50 11 39 45 0 158 2 amappl16 200 11384 0 11123 41 26 15 27 0 8 0 amappl15 192 16 0 16 1 1 0 1 0 8 0 amappl14 184 170 0 157 2 1 1 2 0 8 0 amappl13 176 13 0 13 1 1 0 1 0 8 0 amappl12 168 3922 0 3886 2 0 2 2 0 8 0 amappl11 160 58 0 46 1 0 1 1 0 8 0 amappl10 152 40 0 30 1 0 1 1 0 8 0 amappl9 144 283 0 283 1 0 1 1 0 8 1 amappl8 136 325 0 237 4 0 4 4 0 8 0 amappl7 128 74 0 60 2 0 2 2 0 8 0 amappl6 120 282 0 262 1 0 1 1 0 8 0 amappl5 112 265 0 256 1 0 1 1 0 8 0 amappl4 104 631 0 595 2 0 2 2 0 8 0 amappl3 96 18884 0 18800 3 0 3 3 0 8 0 amappl2 88 3510 0 3438 3 1 2 3 0 8 0 amappl1 80 20028 0 19501 22 10 12 22 0 8 0 amappl 88 29707 0 29472 7 0 7 7 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 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 128 253 0 253 1 1 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 18 0 17 1 0 1 1 0 8 0 aobjpl 72 142 0 12 3 0 3 3 0 8 0 uaddrrnd 24 3161 0 3128 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3161 0 3128 1 0 1 1 0 8 0 vmmpekpl 168 28188 0 28138 3 0 3 3 0 8 0 vmmpepl 168 206560 0 204320 132 23 109 115 0 357 1 vmsppl 464 3160 0 3128 7 2 5 6 0 8 0 rwobjpl 56 62820 0 56165 98 3 95 95 0 8 0 pdppl 4096 6330 0 6256 204 122 82 94 0 8 8 pvpl 32 1127282 0 1110700 332 88 244 332 0 265 99 pmappl 248 3160 0 3128 4 1 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1160 0 253 27 0 27 27 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1e: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff82c1fff0) at x86_ipi_db+0x1e sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_lock(ffffffff82c97058) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82c97058) at __mp_lock+0x122 sys/kern/kern_lock.c:147 intr_handler(ffff8000293b1780,ffff80000027b500) at intr_handler+0x62 sys/arch/amd64/amd64/intr.c:532 Xintr_ioapic_edge25_untramp() at Xintr_ioapic_edge25_untramp+0x18f __mp_lock(ffffffff82c97058) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82c97058) at __mp_lock+0x122 sys/kern/kern_lock.c:147 syscall(ffff8000293b1950) at syscall+0x5cd mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff8000293b1950) at syscall+0x5cd sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7c5e161d72a0, count: -9 ddb{0}> machine ddbcpu 1 Stopped at witness_checkorder+0x1ec: movl 0x8(%r14),%ebx ddb{1}> trace witness_checkorder(fffffd806f125e68,9,0) at witness_checkorder+0x1ec sys/kern/subr_witness.c:794 mtx_enter(fffffd806f125e58) at mtx_enter+0x3e sys/kern/kern_lock.c:265 knote_remove(ffff800022d062b0,fffffd806f125e58,fffffd806f125ee0,3,0) at knote_remove+0x20d sys/kern/kern_event.c:1881 knote_fdclose(ffff800022d062b0,3) at knote_fdclose+0xae sys/kern/kern_event.c:1934 fdfree(ffff800022d062b0) at fdfree+0xdf sys/kern/kern_descrip.c:1196 exit1(ffff800022d062b0,0,0,1) at exit1+0x3e4 sys/kern/kern_exit.c:206 sys_exit(ffff800022d062b0,ffff80002615bab0,ffff80002615bb00) at sys_exit+0x1a sys/kern/kern_exit.c:89 syscall(ffff80002615bb80) at syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff80002615bb80) at syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6fe4b2c565d0, count: -9