witness: lock order reversal: 1st 0xffff800001c016d8 vmmaplk (&map->lock) 2nd 0xffff800001c9d6c0 inode (&ip->i_lock) lock order [1] vmmaplk (&map->lock) -> [2] inode (&ip->i_lock) #0 rw_do_enter_write+0xc4 sys/kern/kern_rwlock.c:234 #1 rrw_enter+0xf0 sys/kern/kern_rwlock.c:621 #2 VOP_LOCK+0x17e sys/kern/vfs_vops.c:527 #3 vn_lock+0xca sys/kern/vfs_vnops.c:576 #4 vn_rdwr+0x138 sys/kern/vfs_vnops.c:326 #5 vndstrategy+0x8e4 sys/dev/vnd.c:342 #6 physio+0x581 sys/kern/kern_physio.c:162 #7 spec_write+0x24b sys/kern/spec_vnops.c:302 #8 VOP_WRITE+0x1a8 sys/kern/vfs_vops.c:245 #9 vn_write+0x295 sys/kern/vfs_vnops.c:414 #10 dofilewritev+0x3ef sys/kern/sys_generic.c:384 #11 sys_write+0x141 sys/kern/sys_generic.c:300 #12 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline] #12 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791 #13 Xsyscall+0x128 lock order [2] inode (&ip->i_lock) -> [1] vmmaplk (&map->lock) #0 rw_do_enter_read+0x8b sys/kern/kern_rwlock.c:355 #1 uvmfault_lookup+0x1a2 sys/uvm/uvm_fault.c:-1 #2 uvm_fault_check+0x43 sys/uvm/uvm_fault.c:693 #3 uvm_fault+0x1e7 sys/uvm/uvm_fault.c:627 #4 kpageflttrap+0x41e sys/arch/amd64/amd64/trap.c:285 #5 kerntrap+0x1b6 sys/arch/amd64/amd64/trap.c:532 #6 alltraps_kern_meltdown+0x7b #7 copyout+0x59 #8 ffs_read+0x701 sys/ufs/ffs/ffs_vnops.c:254 #9 VOP_READ+0x1a8 sys/kern/vfs_vops.c:227 #10 vn_rdwr+0x1bc sys/kern/vfs_vnops.c:-1 #11 vmcmd_map_readvn+0x20a sys/kern/exec_subr.c:250 #12 exec_process_vmcmds+0x164 sys/kern/exec_subr.c:139 #13 sys_execve+0x1354 sys/kern/kern_exec.c:535 #14 start_init+0x5fb sys/kern/init_main.c:732 #15 proc_trampoline+0x10 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(ffff800001c9d6c0,9,0) at witness_checkorder+0x19db sys/kern/subr_witness.c:-1 rw_do_enter_write(ffff800001c9d6a8,1) at rw_do_enter_write+0xc4 sys/kern/kern_rwlock.c:234 rrw_enter(ffff800001c9d6a8,1) at rrw_enter+0xf0 sys/kern/kern_rwlock.c:621 VOP_LOCK(ffff800001c92638,2001) at VOP_LOCK+0x17e sys/kern/vfs_vops.c:527 vn_lock(ffff800001c92638,2001) at vn_lock+0xca sys/kern/vfs_vnops.c:576 vn_rdwr(1,ffff800001c92638,ffff800011b06980,28,0,1,ffff800000d9c5b8,ffff800001b7abb0,ffff800001b7ac20,ffff800028fd3ff0) at vn_rdwr+0x138 sys/kern/vfs_vnops.c:326 vndstrategy(ffff800001b7abb0) at vndstrategy+0x8e4 sys/dev/vnd.c:342 physio(ffffffff810ffa90,2902,0,ffffffff827d0ef0,ffff800039f60660) at physio+0x581 sys/kern/kern_physio.c:162 spec_write(ffff800039f60420) at spec_write+0x24b sys/kern/spec_vnops.c:302 VOP_WRITE(ffff8000019745f0,ffff800039f60660,1,ffff8000001191a0) at VOP_WRITE+0x1a8 sys/kern/vfs_vops.c:245 vn_write(ffff800001bbc2b8,ffff800039f60660,0) at vn_write+0x295 sys/kern/vfs_vnops.c:414 dofilewritev(ffff800045ff7cb0,3,ffff800039f60660,0,ffff800039f60820) at dofilewritev+0x3ef sys/kern/sys_generic.c:384 sys_write(ffff800045ff7cb0,ffff800039f608c0,ffff800039f60820) at sys_write+0x141 sys/kern/sys_generic.c:300 syscall(ffff800039f608c0) at syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800039f608c0) at syscall+0x1089 sys/arch/amd64/amd64/trap.c:791 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x196a6a79570, count: -16 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff800039f5fb80 rbx 0xffffffff84e61480 .str.41 rdx 0 rcx 0xffff800028fd3ff0 rax 0 r8 0xffff800039f5f960 r9 0xffff800039f5f900 r10 0x28 r11 0xffffffff8154eec0 x86_bus_space_io_read_1 r12 0xffffffff84b94bc0 ffs_vget.__lock_type r13 0xffff800001c016d8 r14 0x3 r15 0xffffffff84b94c00 .str.13 rip 0xffffffff8200ee67 db_enter+0x17 cs 0x8 rflags 0x246 rsp 0xffff800039f5fb80 ss 0x10 db_enter+0x17: popq %rbp ddb{1}> show proc PROC (syz-executor) tid=425398 pid=89687 tcnt=4 stat=onproc flags process=0 proc=4000000 runpri=80, usrpri=80, slppri=16, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff800045ff6fb8,0xffffffff85547b20 process=0xffff800029a0d868 user=0xffff800039f55000, vmspace=0xffff800001c015d8 estcpu=30, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND 61003 386996 98139 0 2 0 0 syz-executor 61003 44962 98139 0 2 0 0x4000000 syz-executor 61003 26145 98139 0 2 0 0x4000000 syz-executor 89687 106129 6001 0 2 0 0 syz-executor 89687 5176 6001 0 3 0 0x4000080 fsleep syz-executor 89687 78257 6001 0 3 0 0x4000080 fsleep syz-executor *89687 425398 6001 0 7 0 0x4000000 syz-executor 15359 280620 70778 0 2 0x2 0 syz-executor 70580 437636 70778 0 3 0x2 0x80 piperd syz-executor 6001 332835 70778 0 3 0x2 0x80 nanoslp syz-executor 47244 174283 0 0 3 0x14000 0x200 acct acct 78384 364746 0 0 3 0x14000 0x280 nfsidl nfsio 20532 78214 0 0 3 0x14000 0x280 nfsidl nfsio 30144 122577 0 0 3 0x14000 0x280 nfsidl nfsio 3665 499793 0 0 3 0x14000 0x280 nfsidl nfsio 78032 146694 0 0 3 0x14000 0x280 nfsidl nfsio 59593 89973 0 0 3 0x14000 0x280 nfsidl nfsio 86861 186278 0 0 3 0x14000 0x280 nfsidl nfsio 72636 345108 0 0 3 0x14000 0x280 nfsidl nfsio 21670 137082 0 0 3 0x14000 0x280 nfsidl nfsio 92529 100934 0 0 3 0x14000 0x280 nfsidl nfsio 29454 46780 0 0 3 0x14000 0x280 nfsidl nfsio 94408 195969 0 0 3 0x14000 0x280 nfsidl nfsio 68125 347606 0 0 3 0x14000 0x280 nfsidl nfsio 34012 210653 0 0 3 0x14000 0x280 nfsidl nfsio 56669 354008 0 0 3 0x14000 0x280 nfsidl nfsio 40155 2813 0 0 3 0x14000 0x280 nfsidl nfsio 62350 55208 0 0 3 0x14000 0x280 nfsidl nfsio 40670 414894 0 0 3 0x14000 0x280 nfsidl nfsio 37209 338020 0 0 3 0x14000 0x280 nfsidl nfsio 33916 355053 0 0 3 0x14000 0x280 nfsidl nfsio 49565 318713 70778 0 3 0x2 0x80 nanoslp syz-executor 98139 405142 70778 0 3 0x2 0x80 nanoslp syz-executor 70778 510954 7752 0 3 0x2 0x80 wait syz-executor 7752 371338 93850 0 3 0x100002 0x88 sigsusp ksh 93850 174090 23903 0 3 0x10 0x88 kqread sshd-session 23903 402634 27603 0 3 0x12 0x80 kqread sshd-session 29613 308455 1 0 3 0x100003 0x80 ttyin getty 27603 447438 1 0 3 0 0x88 kqread sshd 50970 284865 64187 74 3 0x1100012 0x80 bpf pflogd 64187 297684 1 0 3 0 0x80 sbwait pflogd 94071 319733 13461 73 3 0x1100010 0x80 kqread syslogd 13461 377154 1 0 3 0x100002 0x80 sbwait syslogd 28166 235755 1 0 3 0x100000 0x80 kqread resolvd 41054 168318 72421 77 3 0x100012 0x80 kqread dhcpleased 90077 135453 72421 77 3 0x100012 0x80 kqread dhcpleased 72421 299001 1 0 3 0 0x80 kqread dhcpleased 36340 404107 0 0 3 0x14000 0x200 bored smr 39702 195610 0 0 2 0x14000 0x200 zerothread 84748 485259 0 0 3 0x14000 0x200 aiodoned aiodoned 77196 62134 0 0 3 0x14000 0x200 syncer update 93198 482822 0 0 3 0x14000 0x200 cleaner cleaner 91859 319304 0 0 3 0x14000 0x200 reaper reaper 45480 343418 0 0 3 0x14000 0x200 pgdaemon pagedaemon 47312 20537 0 0 3 0x14000 0x200 bored viomb 87047 499794 0 0 3 0x14000 0x40000200 acpi0 acpi0 4144 444268 0 0 3 0x14000 0x40000200 idle1 73081 81416 0 0 3 0x14000 0x200 bored softnet1 97869 242170 0 0 2 0x14000 0x200 softnet0 52192 326570 0 0 3 0x14000 0x200 bored systqmp 65594 381888 0 0 3 0x14000 0x200 bored systq 47069 53398 0 0 3 0x14000 0x200 tmoslp softclockmp 768 126950 0 0 3 0x14000 0x40000200 tmoslp softclock 52791 369917 0 0 3 0x14000 0x40000200 idle0 1 472707 0 0 3 0x2 0x80 wait init 0 0 -1 0 3 0x10010000 0x200 scheduler swapper ddb{1}> show all locks Process 89687 (syz-executor) thread 0xffff800045ff7cb0 (425398) shared rwlock vmmaplk r = 0 (0xffff800001c016d8) #0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x632 sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x55d sys/kern/kern_rwlock.c:413 #2 uvm_vslock_device+0x1bc sys/uvm/uvm_glue.c:173 #3 physio+0x4a7 sys/kern/kern_physio.c:139 #4 spec_write+0x24b sys/kern/spec_vnops.c:302 #5 VOP_WRITE+0x1a8 sys/kern/vfs_vops.c:245 #6 vn_write+0x295 sys/kern/vfs_vnops.c:414 #7 dofilewritev+0x3ef sys/kern/sys_generic.c:384 #8 sys_write+0x141 sys/kern/sys_generic.c:300 #9 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline] #9 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791 #10 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8558dbc0) #0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x632 sys/kern/subr_witness.c:1160 #1 vn_write+0x65 sys/kern/vfs_vnops.c:402 #2 dofilewritev+0x3ef sys/kern/sys_generic.c:384 #3 sys_write+0x141 sys/kern/sys_generic.c:300 #4 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline] #4 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791 #5 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11062 12261K 12422K 166960K 12537 0 pcb 17 24K 24K 166960K 54 0 rtable 236 21K 31K 166960K 2430 0 pf 32 21K 49K 166960K 212 0 ifaddr 39 13K 17K 166960K 332 0 ifgroup 51 2K 2K 166960K 343 0 sysctl 4 1K 13K 166960K 12 0 counters 68 42K 44K 166960K 222 0 ioctlops 3 1K 185K 166960K 1682 0 iov 1 0K 16K 166960K 16 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1398 90K 95K 166960K 2463 0 UFS quota 1 36K 36K 166960K 1 0 UFS mount 5 44K 44K 166960K 5 0 shm 2 2K 6K 166960K 8 0 VM map 2 1K 1K 166960K 2 0 sem 60 2K 2K 166960K 90 0 dirhash 15 2K 2K 166960K 15 0 ACPI 1734 201K 413K 166960K 11964 0 file desc 18 50K 121K 166960K 1510 0 sigio 0 0K 0K 166960K 1 0 proc 127 131K 195K 166960K 2538 0 subproc 72 9K 14K 166960K 702 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 20K 20K 166960K 1 0 ip_moptions 0 0K 0K 166960K 10 0 in_multi 88 6K 8K 166960K 858 0 ether_multi 1 0K 0K 166960K 1 0 mrt 5 0K 0K 166960K 37 0 ISOFS mount 1 36K 36K 166960K 1 0 MSDOSFS mount 1 20K 20K 166960K 1 0 ttys 91 627K 627K 166960K 91 0 exec 32 8K 17K 166960K 1307 0 fusefs mount 1 36K 36K 166960K 1 0 pfkey data 0 0K 0K 166960K 3 0 tdb 3 1K 1K 166960K 3 0 VM swap 14 124K 124K 166960K 15 0 UVM amap 469 327K 375K 166960K 11826 0 UVM aobj 13 8K 8K 166960K 14 0 pinsyscall 147 255K 385K 166960K 4503 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 12 0 NDP 21 1K 2K 166960K 240 0 temp 467 9354K 9462K 166960K 18142 0 kqueue 14 44K 84K 166960K 74 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 28 0 0 1 0 1 1 0 8 0 rtpcb 120 176 0 173 1 0 1 1 0 8 0 rtentry 176 874 0 775 6 1 5 6 0 8 0 unpcb 144 630 0 613 5 1 4 4 0 8 3 syncache 336 4 0 4 1 1 0 1 0 8 0 tcpcb 736 35 0 31 1 0 1 1 0 8 0 arp 136 157 0 141 1 0 1 1 0 8 0 inpcb 328 737 0 730 11 5 6 6 0 8 5 nd6 152 234 0 213 2 1 1 2 0 8 0 pkpcb 40 8 0 8 2 2 0 1 0 8 0 kcovpl 48 78 0 70 1 0 1 1 0 8 0 ppxss 1192 6 0 6 3 3 0 1 0 8 0 pffrag 232 1 0 0 1 0 1 1 0 482 0 pffrnode 88 1 0 0 1 0 1 1 0 8 0 pffrent 40 2 0 1 2 1 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 pfanchor 1288 4 0 0 1 0 1 1 0 8 0 pfstitem 24 64 0 25 1 0 1 1 0 8 0 pfstkey 128 64 0 25 2 0 2 2 0 8 0 pfstate 448 64 0 25 6 0 6 6 0 8 0 pfrule 1360 23 0 18 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 3517 0 3100 34 5 29 29 0 8 2 art_table 40 3518 0 3100 5 0 5 5 0 8 0 art_node 32 874 0 784 1 0 1 1 0 8 0 sysvmsgpl 40 3 0 3 2 1 1 1 0 8 1 semupl 112 2 0 2 2 2 0 1 0 8 0 semapl 72 87 0 62 1 0 1 1 0 8 0 shmpl 120 11 0 1 1 0 1 1 0 8 0 dirhash 1024 19 0 0 3 0 3 3 0 8 0 dino2pl 256 2403 0 777 102 0 102 102 0 8 0 ffsino 296 2403 0 777 126 0 126 126 0 8 0 nchpl 144 3072 0 1141 72 0 72 72 0 8 0 rtmask 32 2 0 2 1 1 0 1 0 8 0 vnodes 216 3298 0 0 184 0 184 184 0 8 0 namei 1024 19101 0 19101 3 2 1 2 0 8 1 percpumem 16 127 0 77 1 0 1 1 0 8 0 kstatmem 264 175 0 150 2 0 2 2 0 8 0 scxspl 216 10151 0 10151 12 10 2 8 1 8 2 plimitpl 152 116 0 98 1 0 1 1 0 8 0 sigapl 424 1722 0 1658 10 2 8 8 0 8 0 knotepl 120 146 0 0 5 0 5 5 0 8 0 kqueuepl 224 432 0 423 8 5 3 5 0 8 2 pipepl 344 403 0 376 4 1 3 4 0 8 0 fdescpl 528 1684 0 1658 3 0 3 3 0 8 0 filepl 160 7319 0 7048 22 7 15 18 0 8 3 lockfpl 104 100 0 98 1 0 1 1 0 8 0 lockfspl 48 42 0 40 1 0 1 1 0 8 0 sessionpl 144 104 0 95 1 0 1 1 0 8 0 pgrppl 48 186 0 169 1 0 1 1 0 8 0 ucredpl 104 1398 0 1384 1 0 1 1 0 8 0 zombiepl 144 1662 0 1658 1 0 1 1 0 8 0 processpl 1240 1722 0 1658 7 1 6 6 0 8 0 procpl 664 2416 0 2347 8 1 7 7 0 8 0 sockpl 752 1562 0 1535 15 5 10 10 0 8 7 mcl64k 65536 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k128 9344 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 121 0 0 16 0 16 16 0 8 0 mcl2k 2048 26 0 0 4 0 4 4 0 8 0 mextrefs 64 27 0 0 1 0 1 1 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 284 0 0 18 0 18 18 0 8 0 bufpl 272 3001 0 107 193 0 193 193 0 8 0 anonpl 32 5517 0 0 45 0 45 45 0 222 0 amapchunkpl 152 32548 0 32197 27 6 21 25 0 158 5 amappl16 200 2281 0 2267 5 3 2 5 0 8 0 amappl15 192 7 0 7 3 3 0 1 0 8 0 amappl14 184 1290 0 1289 1 0 1 1 0 8 0 amappl13 176 272 0 259 1 0 1 1 0 8 0 amappl12 168 2233 0 2208 2 0 2 2 0 8 0 amappl11 160 5 0 4 1 0 1 1 0 8 0 amappl10 152 65 0 51 1 0 1 1 0 8 0 amappl9 144 268 0 268 1 1 0 1 0 8 0 amappl8 136 405 0 402 1 0 1 1 0 8 0 amappl7 128 319 0 306 1 0 1 1 0 8 0 amappl6 120 846 0 845 1 0 1 1 0 8 0 amappl5 112 119 0 108 1 0 1 1 0 8 0 amappl4 104 519 0 498 1 0 1 1 0 8 0 amappl3 96 6190 0 6119 3 0 3 3 0 8 0 amappl2 88 1547 0 1473 2 0 2 2 0 8 0 amappl1 80 21063 0 20483 18 5 13 15 0 8 0 amappl 88 9850 0 9729 5 1 4 5 0 92 0 uvmvnodes 80 109 0 0 3 0 3 3 0 8 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 13 0 1 1 0 1 1 0 8 0 uaddrrnd 24 1684 0 1658 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1684 0 1658 1 0 1 1 0 8 0 vmmpekpl 168 15365 0 15323 3 0 3 3 0 8 0 vmmpepl 168 115841 0 114209 91 8 83 87 0 357 1 vmsppl 488 1683 0 1657 5 0 5 5 0 8 0 rwobjpl 80 33810 0 32822 25 1 24 24 0 8 0 pdppl 4096 3377 0 3314 181 110 71 87 0 8 8 pvpl 32 12330 0 0 100 0 100 100 0 265 0 pmappl 256 1683 0 1657 3 0 3 3 0 8 0 extentpl 40 47 0 29 1 0 1 1 0 8 0 phpool 120 573 0 121 14 0 14 14 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x19: leave ddb{0}> trace x86_ipi_db(ffffffff85093ff0) at x86_ipi_db+0x19 sys/arch/amd64/amd64/db_interface.c:412 x86_ipi_handler() at x86_ipi_handler+0x112 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_lock(ffffffff8558d3c0) at __mp_lock+0x270 __mp_lock_spin sys/kern/kern_lock.c:143 [inline] __mp_lock(ffffffff8558d3c0) at __mp_lock+0x270 sys/kern/kern_lock.c:173 intr_handler(ffff800029a27680,ffff800000162480) at intr_handler+0x113 sys/arch/amd64/amd64/intr.c:560 Xintr_ioapic_edge16_untramp() at Xintr_ioapic_edge16_untramp+0x18f __asan_load4_noabort(ffffffff8558dbb8) at __asan_load4_noabort+0x5c kasan_shadow_check sys/kern/subr_kasan.c:1001 [inline] __asan_load4_noabort(ffffffff8558dbb8) at __asan_load4_noabort+0x5c sys/kern/subr_kasan.c:1098 __mp_lock(ffffffff8558d3c0) at __mp_lock+0x27a __mp_lock_spin sys/kern/kern_lock.c:142 [inline] __mp_lock(ffffffff8558d3c0) at __mp_lock+0x27a sys/kern/kern_lock.c:173 softintr_dispatch(0) at softintr_dispatch+0x215 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x7b sys/arch/amd64/amd64/intr.c:862 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8558d3c0) at __mp_lock+0x272 __mp_lock_spin sys/kern/kern_lock.c:142 [inline] __mp_lock(ffffffff8558d3c0) at __mp_lock+0x272 sys/kern/kern_lock.c:173 exit1(ffff800045ff5cb8,0,0,1) at exit1+0xa5d sys/kern/kern_exit.c:262 sys_exit(ffff800045ff5cb8,ffff800029a27bc0,ffff800029a27b20) at sys_exit+0x4a syscall(ffff800029a27bc0) at syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800029a27bc0) at syscall+0x1089 sys/arch/amd64/amd64/trap.c:791 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x732842d384b0, count: -16 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x17: popq %rbp ddb{1}> trace db_enter() at db_enter+0x17 sys/arch/amd64/amd64/db_interface.c:457 witness_checkorder(ffff800001c9d6c0,9,0) at witness_checkorder+0x19db sys/kern/subr_witness.c:-1 rw_do_enter_write(ffff800001c9d6a8,1) at rw_do_enter_write+0xc4 sys/kern/kern_rwlock.c:234 rrw_enter(ffff800001c9d6a8,1) at rrw_enter+0xf0 sys/kern/kern_rwlock.c:621 VOP_LOCK(ffff800001c92638,2001) at VOP_LOCK+0x17e sys/kern/vfs_vops.c:527 vn_lock(ffff800001c92638,2001) at vn_lock+0xca sys/kern/vfs_vnops.c:576 vn_rdwr(1,ffff800001c92638,ffff800011b06980,28,0,1,ffff800000d9c5b8,ffff800001b7abb0,ffff800001b7ac20,ffff800028fd3ff0) at vn_rdwr+0x138 sys/kern/vfs_vnops.c:326 vndstrategy(ffff800001b7abb0) at vndstrategy+0x8e4 sys/dev/vnd.c:342 physio(ffffffff810ffa90,2902,0,ffffffff827d0ef0,ffff800039f60660) at physio+0x581 sys/kern/kern_physio.c:162 spec_write(ffff800039f60420) at spec_write+0x24b sys/kern/spec_vnops.c:302 VOP_WRITE(ffff8000019745f0,ffff800039f60660,1,ffff8000001191a0) at VOP_WRITE+0x1a8 sys/kern/vfs_vops.c:245 vn_write(ffff800001bbc2b8,ffff800039f60660,0) at vn_write+0x295 sys/kern/vfs_vnops.c:414 dofilewritev(ffff800045ff7cb0,3,ffff800039f60660,0,ffff800039f60820) at dofilewritev+0x3ef sys/kern/sys_generic.c:384 sys_write(ffff800045ff7cb0,ffff800039f608c0,ffff800039f60820) at sys_write+0x141 sys/kern/sys_generic.c:300 syscall(ffff800039f608c0) at syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800039f608c0) at syscall+0x1089 sys/arch/amd64/amd64/trap.c:791 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x196a6a79570, count: -16