uvm_fault(0xfffffd806ba62598, 0x8, 0, 1) -> e kernel: page fault trap, code=0 Stopped at witness_checkorder+0x1ec: movl 0x8(%r14),%ebx TID PID UID PRFLAGS PFLAGS CPU COMMAND 512608 82628 0 0x14000 0x200 0 reaper witness_checkorder(fffffd806f2bd1c0,9,0) at witness_checkorder+0x1ec sys/kern/subr_witness.c:794 mtx_enter(fffffd806f2bd1b0) at mtx_enter+0x3e sys/kern/kern_lock.c:265 knote_remove(ffff80002129d7f0,fffffd806f2bd1b0,fffffd806f2bd238,3,0) at knote_remove+0x20d sys/kern/kern_event.c:1881 knote_fdclose(ffff80002129d7f0,3) at knote_fdclose+0xae sys/kern/kern_event.c:1934 fdfree(ffff80002129d7f0) at fdfree+0xdf sys/kern/kern_descrip.c:1196 exit1(ffff80002129d7f0,0,0,1) at exit1+0x3ff sys/kern/kern_exit.c:206 sys_exit(ffff80002129d7f0,ffff80002139da30,ffff80002139da80) at sys_exit+0x1a sys/kern/kern_exit.c:89 syscall(ffff80002139db00) at syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff80002139db00) at syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee42173c4a0, count: 6 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: uvm_fault(0xfffffd806ba62598, 0x8, 0, 1) -> e ddb{1}> trace witness_checkorder(fffffd806f2bd1c0,9,0) at witness_checkorder+0x1ec sys/kern/subr_witness.c:794 mtx_enter(fffffd806f2bd1b0) at mtx_enter+0x3e sys/kern/kern_lock.c:265 knote_remove(ffff80002129d7f0,fffffd806f2bd1b0,fffffd806f2bd238,3,0) at knote_remove+0x20d sys/kern/kern_event.c:1881 knote_fdclose(ffff80002129d7f0,3) at knote_fdclose+0xae sys/kern/kern_event.c:1934 fdfree(ffff80002129d7f0) at fdfree+0xdf sys/kern/kern_descrip.c:1196 exit1(ffff80002129d7f0,0,0,1) at exit1+0x3ff sys/kern/kern_exit.c:206 sys_exit(ffff80002129d7f0,ffff80002139da30,ffff80002139da80) at sys_exit+0x1a sys/kern/kern_exit.c:89 syscall(ffff80002139db00) at syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff80002139db00) at syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee42173c4a0, count: -9 ddb{1}> show registers rdi 0 rsi 0x20000 acpi_pdirpa+0xbe63 rbp 0xffff80002139d7d0 rbx 0xe rdx 0 rcx 0xfffffd80037e3460 rax 0xffff800020d58ff0 r8 0x1 r9 0x1 r10 0x59f70afdcfd35571 r11 0xd0b4d0d8661ebebe r12 0 r13 0xfffffd806f2bd1c0 r14 0 r15 0xffff80002129d7f0 rip 0xffffffff81b8d00c witness_checkorder+0x1ec cs 0x8 rflags 0x10246 __ALIGN_SIZE+0xf246 rsp 0xffff80002139d720 ss 0x10 witness_checkorder+0x1ec: movl 0x8(%r14),%ebx ddb{1}> show proc PROC (syz-executor.6) pid=348779 stat=onproc flags process=1018 proc=2000 pri=0, usrpri=71, nice=20 forw=0xffffffffffffffff, list=0xffff80002129cd50,0xffff80002129d008 process=0xffff80002141d0e0 user=0xffff800021398000, vmspace=0xfffffd806ba62598 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 72874 461874 16500 32767 2 0x10 syz-executor.0 72874 315294 16500 32767 2 0x4000010 syz-executor.0 18316 487713 74545 32767 2 0x10 syz-executor.2 31069 417735 70411 32767 2 0x10 syz-executor.3 31069 83214 70411 32767 3 0x4000090 fsleep syz-executor.3 24164 485120 50422 32767 2 0x10 syz-executor.4 24164 249597 50422 32767 2 0x4000010 syz-executor.4 36281 256623 4086 32767 2 0x10 syz-executor.5 36281 166578 4086 32767 3 0x4000090 fsleep syz-executor.5 79793 189596 0 0 3 0x14200 bored sosplice 50422 299654 34497 32767 3 0x90 nanoslp syz-executor.4 12612 372484 93373 32767 3 0x90 nanoslp syz-executor.6 16500 217720 60296 32767 3 0x90 nanoslp syz-executor.0 29984 336917 70131 32767 2 0x10 syz-executor.7 34497 47351 27897 0 3 0x82 wait syz-executor.4 93373 37212 27897 0 3 0x82 wait syz-executor.6 70131 131079 27897 0 3 0x82 wait syz-executor.7 4086 162340 96493 32767 3 0x90 nanoslp syz-executor.5 74545 184776 6625 32767 3 0x90 nanoslp syz-executor.2 60296 436220 27897 0 3 0x82 wait syz-executor.0 96493 147195 27897 0 3 0x82 wait syz-executor.5 70411 71368 14637 32767 3 0x90 nanoslp syz-executor.3 6625 488022 27897 0 3 0x82 wait syz-executor.2 99314 196886 23967 32767 3 0x10 biowait syz-executor.1 23967 268680 27897 0 3 0x82 wait syz-executor.1 14637 365795 27897 0 3 0x82 wait syz-executor.3 27897 512241 36848 0 3 0x2000082 wait syz-execprog 27897 68766 36848 0 3 0x6000082 nanoslp syz-execprog 27897 289846 36848 0 3 0x6000082 wait syz-execprog 27897 318747 36848 0 3 0x6000082 wait syz-execprog 27897 109790 36848 0 3 0x6000082 wait syz-execprog 27897 157901 36848 0 3 0x6000082 thrsleep syz-execprog 27897 207551 36848 0 3 0x6000082 thrsleep syz-execprog 27897 373851 36848 0 3 0x6000082 wait syz-execprog 27897 384142 36848 0 3 0x6000082 wait syz-execprog 27897 79290 36848 0 3 0x6000082 thrsleep syz-execprog 27897 42338 36848 0 3 0x6000082 wait syz-execprog 27897 76885 36848 0 3 0x6000082 wait syz-execprog 27897 191280 36848 0 3 0x6000082 kqread syz-execprog 27897 370325 36848 0 3 0x6000082 thrsleep syz-execprog 27897 25985 36848 0 3 0x6000082 thrsleep syz-execprog 36848 338651 61369 0 3 0x10008a sigsusp ksh 61369 201455 85351 0 3 0x9a kqread sshd 64969 88192 1 0 3 0x100083 ttyin getty 85351 306604 1 0 3 0x88 kqread sshd 99767 367367 50831 73 3 0x1100090 kqread syslogd 50831 111464 1 0 3 0x100082 netio syslogd 15599 444964 1 0 3 0x100080 kqread resolvd 12287 334116 39006 77 3 0x100092 kqread dhcpleased 58999 453508 39006 77 3 0x100092 kqread dhcpleased 39006 242801 1 0 3 0x80 kqread dhcpleased 60505 412926 0 0 3 0x14200 bored smr 15967 21193 0 0 2 0x14200 zerothread 55729 250950 0 0 3 0x14200 aiodoned aiodoned 97208 144273 0 0 3 0x14200 syncer update 11347 321472 0 0 3 0x14200 cleaner cleaner 82628 512608 0 0 7 0x14200 reaper 79269 445247 0 0 3 0x14200 pgdaemon pagedaemon 51961 317653 0 0 3 0x14200 bored viomb 68889 110268 0 0 3 0x40014200 acpi0 acpi0 582 426662 0 0 3 0x40014200 idle1 70265 118708 0 0 3 0x14200 bored softnet3 39473 33574 0 0 3 0x14200 bored softnet2 71037 226557 0 0 3 0x14200 bored softnet1 38828 275399 0 0 3 0x14200 bored softnet0 60731 382310 0 0 3 0x14200 bored systqmp 36608 504161 0 0 3 0x14200 bored systq 78350 132174 0 0 3 0x40014200 bored softclock 36612 355906 0 0 3 0x40014200 idle0 1 513411 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 0: exclusive sched_lock &sched_lock r = 0 (0xffffffff82cdefb0) #0 witness_lock+0x447 #1 wakeup_n+0x37 sys/kern/kern_synch.c:541 #2 uvm_pmr_getpages+0xeef sys/uvm/uvm_pmemrange.c:1207 #3 uvm_pagealloc+0x1a8 sys/uvm/uvm_page.c:910 #4 pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1209 #5 pmap_enter+0x2be sys/arch/amd64/amd64/pmap.c:2716 #6 uvm_fault_lower+0x768 sys/uvm/uvm_fault.c:1505 #7 uvm_fault+0x238 #8 upageflttrap+0x86 sys/arch/amd64/amd64/trap.c:188 #9 usertrap+0x226 sys/arch/amd64/amd64/trap.c:436 #10 recall_trap+0x8 exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff82d26320) #0 witness_lock+0x447 #1 mtx_enter_try+0x104 #2 mtx_enter+0x4f sys/kern/kern_lock.c:266 #3 uvm_pmr_getpages+0xeac sys/uvm/uvm_pmemrange.c:1205 #4 uvm_pagealloc+0x1a8 sys/uvm/uvm_page.c:910 #5 pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1209 #6 pmap_enter+0x2be sys/arch/amd64/amd64/pmap.c:2716 #7 uvm_fault_lower+0x768 sys/uvm/uvm_fault.c:1505 #8 uvm_fault+0x238 #9 upageflttrap+0x86 sys/arch/amd64/amd64/trap.c:188 #10 usertrap+0x226 sys/arch/amd64/amd64/trap.c:436 #11 recall_trap+0x8 exclusive mutex &pmap->pm_mtx r = 0 (0xfffffd806c4753f0) #0 witness_lock+0x447 #1 mtx_enter_try+0x104 #2 mtx_enter+0x4f sys/kern/kern_lock.c:266 #3 pmap_enter+0x1c3 pmap_map_ptes sys/arch/amd64/amd64/pmap.c:423 [inline] #3 pmap_enter+0x1c3 sys/arch/amd64/amd64/pmap.c:2710 #4 uvm_fault_lower+0x768 sys/uvm/uvm_fault.c:1505 #5 uvm_fault+0x238 #6 upageflttrap+0x86 sys/arch/amd64/amd64/trap.c:188 #7 usertrap+0x226 sys/arch/amd64/amd64/trap.c:436 #8 recall_trap+0x8 Process 24164 (syz-executor.4) thread 0xffff800021275298 (249597) exclusive rwlock amaplk r = 0 (0xfffffd806bb78390) #0 witness_lock+0x447 #1 uvm_fault_check+0x41a sys/uvm/uvm_fault.c:782 #2 uvm_fault+0xf2 sys/uvm/uvm_fault.c:600 #3 upageflttrap+0x86 sys/arch/amd64/amd64/trap.c:188 #4 usertrap+0x226 sys/arch/amd64/amd64/trap.c:436 #5 recall_trap+0x8 shared rwlock vmmaplk r = 0 (0xfffffd806ba62860) #0 witness_lock+0x447 #1 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1772 #2 uvm_fault_check+0x3e sys/uvm/uvm_fault.c:672 #3 uvm_fault+0xf2 sys/uvm/uvm_fault.c:600 #4 upageflttrap+0x86 sys/arch/amd64/amd64/trap.c:188 #5 usertrap+0x226 sys/arch/amd64/amd64/trap.c:436 #6 recall_trap+0x8 Process 99314 (syz-executor.1) thread 0xffff800021200810 (196886) exclusive rrwlock inode r = 0 (0xfffffd806b6602c8) #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 (0xfffffd806bd66e70) #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 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10181 6407K 6420K 78643K 11259 0 pcb 13 8K 8K 78643K 13 0 rtable 234 6K 6K 78643K 344 0 pf 29 8K 8K 78643K 29 0 ifaddr 44 15K 15K 78643K 46 0 ifgroup 50 2K 2K 78643K 50 0 counters 60 35K 35K 78643K 60 0 ioctlops 0 0K 2K 78643K 29 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1174 73K 74K 78643K 1187 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 1K 1K 78643K 2 0 sem 2 0K 0K 78643K 2 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 24 89K 125K 78643K 405 0 proc 56 78K 103K 78643K 471 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 99 7K 7K 78643K 99 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 25 122K 122K 78643K 25 0 exec 0 0K 1K 78643K 356 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 281 77K 77K 78643K 5412 0 UVM aobj 3 2K 2K 78643K 3 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 11 0K 2K 78643K 27 0 temp 1 5904K 5968K 78643K 4421 0 kqueue 12 18K 26K 78643K 282 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 33 0 30 1 0 1 1 0 8 0 rtentry 112 111 0 1 4 0 4 4 0 8 0 unpcb 144 33 0 20 1 0 1 1 0 8 0 syncache 304 5 0 5 2 1 1 1 0 8 1 tcpqe 32 166 0 166 1 1 0 1 0 8 0 tcpcb 808 8 0 5 1 0 1 1 0 8 0 arp 120 18 0 0 1 0 1 1 0 8 0 inpcb 368 319 0 310 2 0 2 2 0 8 1 nd6 136 24 0 0 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 452 0 0 29 0 29 29 0 8 0 art_table 32 453 0 0 4 0 4 4 0 8 0 art_node 16 110 0 10 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1747 0 308 90 0 90 90 0 8 0 ffsino 272 1747 0 308 96 0 96 96 0 8 0 nchpl 144 2261 0 585 63 0 63 63 0 8 0 uvmvnodes 80 1756 0 0 36 0 36 36 0 8 0 vnodes 216 1756 0 0 98 0 98 98 0 8 0 namei 1024 7027 0 7027 4 1 3 3 0 8 3 percpumem 16 43 0 0 1 0 1 1 0 8 0 kstatmem 264 22 0 0 2 0 2 2 0 8 0 scxspl 216 8163 0 8162 10 9 1 8 1 8 0 plimitpl 152 42 0 19 1 0 1 1 0 8 0 sigapl 424 695 0 642 7 0 7 7 0 8 0 futexpl 64 1191 0 1189 1 0 1 1 0 8 0 knotepl 120 114 0 0 4 0 4 4 0 8 0 kqueuepl 216 280 0 272 1 0 1 1 0 8 0 pipepl 320 136 0 108 4 1 3 3 0 8 0 fdescpl 496 677 0 642 7 1 6 6 0 8 1 filepl 152 2080 0 1949 6 0 6 6 0 8 0 lockfpl 104 6 0 4 1 0 1 1 0 8 0 lockfspl 48 4 0 2 1 0 1 1 0 8 0 sessionpl 144 25 0 9 1 0 1 1 0 8 0 pgrppl 48 25 0 9 1 0 1 1 0 8 0 ucredpl 104 90 0 72 1 0 1 1 0 8 0 zombiepl 144 643 0 642 2 1 1 1 0 8 0 processpl 1072 695 0 642 5 0 5 5 0 8 0 procpl 680 977 0 906 7 0 7 7 0 8 0 sosppl 168 255 0 253 1 0 1 1 0 8 0 sockpl 488 385 0 360 4 0 4 4 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 255 0 0 32 2 30 32 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 359 0 0 18 1 17 18 0 8 0 bufpl 288 4368 0 141 302 0 302 302 0 8 0 anonpl 24 214644 0 209982 68 13 55 55 0 186 26 amapchunkpl 152 17959 0 17264 30 1 29 29 0 158 2 amappl16 200 5951 0 5877 10 5 5 5 0 8 0 amappl15 192 10 0 10 1 1 0 1 0 8 0 amappl14 184 175 0 162 2 0 2 2 0 8 1 amappl13 176 15 0 14 2 1 1 1 0 8 0 amappl12 168 1310 0 1274 3 0 3 3 0 8 0 amappl11 160 54 0 44 1 0 1 1 0 8 0 amappl10 152 26 0 18 2 1 1 1 0 8 0 amappl9 144 185 0 185 2 1 1 1 0 8 1 amappl8 136 154 0 126 2 0 2 2 0 8 0 amappl7 128 75 0 61 2 0 2 2 0 8 0 amappl6 120 222 0 205 2 0 2 2 0 8 1 amappl5 112 164 0 156 1 0 1 1 0 8 0 amappl4 104 542 0 506 2 0 2 2 0 8 0 amappl3 96 4026 0 3935 3 0 3 3 0 8 0 amappl2 88 916 0 846 4 1 3 3 0 8 1 amappl1 80 11596 0 11063 27 6 21 22 0 8 8 amappl 88 4948 0 4742 5 0 5 5 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 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 677 0 642 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 677 0 642 1 0 1 1 0 8 0 vmmpekpl 168 11130 0 11096 2 0 2 2 0 8 0 vmmpepl 168 57894 0 56035 120 9 111 111 0 357 28 vmsppl 464 676 0 642 7 1 6 6 0 8 1 rwobjpl 56 24575 0 21841 46 1 45 45 0 8 6 pdppl 4096 1362 0 1284 120 38 82 96 0 8 4 pvpl 32 452571 0 442217 366 30 336 345 0 265 248 pmappl 248 676 0 642 4 1 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 710 0 44 20 0 20 20 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1e: addq $0x8,%rsp x86_ipi_db(ffffffff82bffff0) 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(ffffffff82cd6528) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82cd6528) at __mp_lock+0x129 sys/kern/kern_lock.c:147 intr_handler(ffff8000211b8e40,ffff80000006bc00) at intr_handler+0x62 sys/arch/amd64/amd64/intr.c:532 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f mtx_leave(ffffffff82c98a58) at mtx_leave+0xf6 sys/kern/kern_lock.c:374 reaper(ffff8000211b2ff8) at reaper+0xdb sys/kern/kern_exit.c:435 end trace frame: 0x0, count: 7 ddb{0}> trace x86_ipi_db(ffffffff82bffff0) 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(ffffffff82cd6528) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82cd6528) at __mp_lock+0x129 sys/kern/kern_lock.c:147 intr_handler(ffff8000211b8e40,ffff80000006bc00) at intr_handler+0x62 sys/arch/amd64/amd64/intr.c:532 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f mtx_leave(ffffffff82c98a58) at mtx_leave+0xf6 sys/kern/kern_lock.c:374 reaper(ffff8000211b2ff8) at reaper+0xdb sys/kern/kern_exit.c:435 end trace frame: 0x0, count: -8 ddb{0}> machine ddbcpu 1 Stopped at witness_checkorder+0x1ec: movl 0x8(%r14),%ebx witness_checkorder(fffffd806f2bd1c0,9,0) at witness_checkorder+0x1ec sys/kern/subr_witness.c:794 mtx_enter(fffffd806f2bd1b0) at mtx_enter+0x3e sys/kern/kern_lock.c:265 knote_remove(ffff80002129d7f0,fffffd806f2bd1b0,fffffd806f2bd238,3,0) at knote_remove+0x20d sys/kern/kern_event.c:1881 knote_fdclose(ffff80002129d7f0,3) at knote_fdclose+0xae sys/kern/kern_event.c:1934 fdfree(ffff80002129d7f0) at fdfree+0xdf sys/kern/kern_descrip.c:1196 exit1(ffff80002129d7f0,0,0,1) at exit1+0x3ff sys/kern/kern_exit.c:206 sys_exit(ffff80002129d7f0,ffff80002139da30,ffff80002139da80) at sys_exit+0x1a sys/kern/kern_exit.c:89 syscall(ffff80002139db00) at syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff80002139db00) at syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee42173c4a0, count: 6 ddb{1}> trace witness_checkorder(fffffd806f2bd1c0,9,0) at witness_checkorder+0x1ec sys/kern/subr_witness.c:794 mtx_enter(fffffd806f2bd1b0) at mtx_enter+0x3e sys/kern/kern_lock.c:265 knote_remove(ffff80002129d7f0,fffffd806f2bd1b0,fffffd806f2bd238,3,0) at knote_remove+0x20d sys/kern/kern_event.c:1881 knote_fdclose(ffff80002129d7f0,3) at knote_fdclose+0xae sys/kern/kern_event.c:1934 fdfree(ffff80002129d7f0) at fdfree+0xdf sys/kern/kern_descrip.c:1196 exit1(ffff80002129d7f0,0,0,1) at exit1+0x3ff sys/kern/kern_exit.c:206 sys_exit(ffff80002129d7f0,ffff80002139da30,ffff80002139da80) at sys_exit+0x1a sys/kern/kern_exit.c:89 syscall(ffff80002139db00) at syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff80002139db00) at syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee42173c4a0, count: -9