witness: userret: returning with the following locks held: exclusive rwlock vmmaplk r = 0 (0xfffffd806c048c68) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x367 sys/kern/kern_rwlock.c:311 #2 vm_map_lock_ln+0x12e sys/uvm/uvm_map.c:5227 #3 uvm_map_pageable_wire+0x588 sys/uvm/uvm_map.c:2128 #4 sys_mlockall+0x85 sys/uvm/uvm_mmap.c:914 #5 syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 #6 Xsyscall+0x128 panic: witness_warn Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 278338 90326 32767 0x10 0x4000000 1 syz-executor * 52887 89095 32767 0x10 0x4000000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83382f2f) at panic+0x1e5 sys/kern/subr_prf.c:198 witness_warn(2,0,ffffffff8333d8ad) at witness_warn+0x850 witness_debugger sys/kern/subr_witness.c:2576 [inline] witness_warn(2,0,ffffffff8333d8ad) at witness_warn+0x850 sys/kern/subr_witness.c:1485 userret(ffff8000ffff0f80) at userret+0x3a4 sys/kern/kern_sig.c:2227 syscall(ffff8000327e4b70) at syscall+0x9c0 mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff8000327e4b70) at syscall+0x9c0 sys/arch/amd64/amd64/trap.c:600 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf94b3e00700, count: 9 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: witness_warn ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83382f2f) at panic+0x1e5 sys/kern/subr_prf.c:198 witness_warn(2,0,ffffffff8333d8ad) at witness_warn+0x850 witness_debugger sys/kern/subr_witness.c:2576 [inline] witness_warn(2,0,ffffffff8333d8ad) at witness_warn+0x850 sys/kern/subr_witness.c:1485 userret(ffff8000ffff0f80) at userret+0x3a4 sys/kern/kern_sig.c:2227 syscall(ffff8000327e4b70) at syscall+0x9c0 mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff8000327e4b70) at syscall+0x9c0 sys/arch/amd64/amd64/trap.c:600 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf94b3e00700, count: -6 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff8000327e48a0 rbx 0xffffffff8386cdd7 cpu_info_full_primary+0x2dd7 rdx 0xffff800001471600 rcx 0xffff8000ffff0f80 rax 0xffffffff8386bff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xf787ae12b9dab394 r11 0x4ff8db271db77a70 r12 0xffffffff8386cbd8 cpu_info_full_primary+0x2bd8 r13 0 r14 0 r15 0x1 rip 0xffffffff82336e45 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff8000327e4890 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=52887 pid=89095 tcnt=3 stat=onproc flags process=10 proc=4000000 runpri=32, usrpri=77, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a2aaf78,0xffff8000ffff14b0 process=0xffff80003c412128 user=0xffff8000327df000, vmspace=0xfffffd806c048b68 estcpu=27, cpticks=50, pctcpu=0.0, user=0, sys=50, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 90326 62880 806 32767 2 0x10 syz-executor 90326 278338 806 32767 7 0x4000010 syz-executor 85970 450874 86744 0 3 0x2 biowait syz-executor 60546 409579 8777 32767 2 0x10 syz-executor 60546 196591 8777 32767 3 0x4000090 fsleep syz-executor 60546 455590 8777 32767 3 0x4000090 fsleep syz-executor 7067 284233 28068 32767 2 0x10 syz-executor 7067 93907 28068 32767 3 0x4000090 fsleep syz-executor 78757 165212 86744 0 2 0x2 syz-executor 92069 329256 4958 32767 3 0x3010 suspend syz-executor 92069 257966 4958 32767 2 0x4081090 syz-executor 89095 214567 56402 32767 2 0x10 syz-executor 89095 356182 56402 32767 3 0x4000090 kqread syz-executor *89095 52887 56402 32767 7 0x4000010 syz-executor 66509 150550 0 0 3 0x14200 bored sosplice 4958 441117 29113 32767 2 0xc90 syz-executor 80115 190490 9944 32767 2 0x10 syz-executor 56402 471844 51080 32767 2 0x10 syz-executor 806 512772 89226 32767 3 0x90 nanoslp syz-executor 28068 298582 14327 32767 3 0x90 nanoslp syz-executor 8777 524024 15957 32767 2 0xc90 syz-executor 89226 409148 86744 0 3 0x82 wait syz-executor 29113 278603 86744 0 3 0x82 wait syz-executor 15957 417585 86744 0 3 0x82 wait syz-executor 51080 302662 86744 0 3 0x82 wait syz-executor 14327 421068 86744 0 3 0x82 wait syz-executor 9944 238622 86744 0 3 0x82 wait syz-executor 86744 323506 61982 0 3 0x82 kqread syz-executor 61982 265796 21114 0 3 0x10008a sigsusp ksh 21114 63494 86101 0 3 0x98 kqread sshd-session 86101 115102 92442 0 3 0x92 kqread sshd-session 6810 206366 1 0 3 0x100083 ttyin getty 92442 358711 1 0 3 0x88 kqread sshd 75637 194113 32956 73 2 0x1100010 syslogd 32956 337215 1 0 3 0x100082 sbwait syslogd 60923 361186 1 0 3 0x100080 kqread resolvd 87466 320426 78507 77 3 0x100092 kqread dhcpleased 53253 382468 78507 77 3 0x100092 kqread dhcpleased 78507 99553 1 0 3 0x80 kqread dhcpleased 84796 191299 0 0 3 0x14200 bored smr 67010 43887 0 0 2 0x14200 zerothread 90788 465912 0 0 3 0x14200 aiodoned aiodoned 48494 521629 0 0 3 0x14200 syncer update 57521 184188 0 0 3 0x14200 cleaner cleaner 17373 519991 0 0 3 0x14200 reaper reaper 7906 55428 0 0 3 0x14200 pgdaemon pagedaemon 54066 189955 0 0 3 0x14200 bored viomb 12478 61437 0 0 3 0x40014200 acpi0 acpi0 39204 184381 0 0 3 0x40014200 idle1 1994 10052 0 0 3 0x14200 bored softnet3 25189 292858 0 0 3 0x14200 bored softnet2 89910 25398 0 0 3 0x14200 bored softnet1 16364 265521 0 0 3 0x14200 bored softnet0 57701 377929 0 0 2 0x14200 systqmp 51980 138708 0 0 3 0x14200 bored systq 44191 441851 0 0 2 0x14200 softclockmp 85835 524111 0 0 3 0x40014200 tmoslp softclock 52021 130886 0 0 3 0x40014200 idle0 1 295802 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 90326 (syz-executor) thread 0xffff8000ffff0020 (62880) exclusive rwlock uobjlk r = 0 (0xfffffd806e0eb180) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x367 sys/kern/kern_rwlock.c:311 #2 uvm_fault_lower_lookup+0x53 sys/uvm/uvm_fault.c:1236 #3 uvm_fault_lower+0x89 sys/uvm/uvm_fault.c:1370 #4 uvm_fault+0x278 sys/uvm/uvm_fault.c:-1 #5 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 #6 usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 #7 recall_trap+0x8 shared rwlock vmmaplk r = 0 (0xfffffd806c18b6c0) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x36e sys/kern/kern_rwlock.c:398 #2 uvmfault_lookup+0x122 sys/uvm/uvm_fault.c:1924 #3 uvm_fault_check+0x4a sys/uvm/uvm_fault.c:741 #4 uvm_fault+0x106 sys/uvm/uvm_fault.c:677 #5 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 #6 usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 #7 recall_trap+0x8 Process 85970 (syz-executor) thread 0xffff8000ffff14a0 (450874) exclusive rrwlock inode r = 0 (0xfffffd8066f01e20) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x367 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:606 #3 VOP_LOCK+0xa6 sys/kern/vfs_vops.c:527 #4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline] #4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:159 #5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1230 #6 ffs_inode_alloc+0x283 sys/ufs/ffs/ffs_alloc.c:393 #7 ufs_mkdir+0x113 sys/ufs/ufs/ufs_vnops.c:1112 #8 VOP_MKDIR+0x102 sys/kern/vfs_vops.c:394 #9 domkdirat+0x179 sys/kern/vfs_syscalls.c:3109 #10 syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] #10 syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 #11 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd807e28f670) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x367 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:606 #3 VOP_LOCK+0xa6 sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vfs_lookup+0x109 sys/kern/vfs_lookup.c:418 #6 namei+0x7aa sys/kern/vfs_lookup.c:250 #7 domkdirat+0x8b sys/kern/vfs_syscalls.c:3094 #8 syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 #9 Xsyscall+0x128 Process 89095 (syz-executor) thread 0xffff8000ffff0f80 (52887) exclusive rwlock vmmaplk r = 0 (0xfffffd806c048c68) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x367 sys/kern/kern_rwlock.c:311 #2 vm_map_lock_ln+0x12e sys/uvm/uvm_map.c:5227 #3 uvm_map_pageable_wire+0x588 sys/uvm/uvm_map.c:2128 #4 sys_mlockall+0x85 sys/uvm/uvm_mmap.c:914 #5 syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 #6 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10185 10950K 10966K 166960K 11268 0 pcb 17 12K 12K 166960K 17 0 rtable 192 5K 7K 166960K 363 0 pf 27 16K 16K 166960K 31 0 ifaddr 34 6K 7K 166960K 44 0 ifgroup 42 1K 2K 166960K 50 0 sysctl 4 1K 9K 166960K 8 0 counters 62 36K 36K 166960K 66 0 ioctlops 0 0K 2K 166960K 29 0 iov 0 0K 12K 166960K 6 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1334 84K 84K 166960K 1382 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 5 0 VM map 2 1K 1K 166960K 2 0 sem 9 0K 0K 166960K 11 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 21 74K 125K 166960K 323 0 sigio 0 0K 0K 166960K 136 0 proc 58 79K 127K 166960K 497 0 subproc 57 3K 4K 166960K 93 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 71 0 in_multi 77 5K 7K 166960K 106 0 ether_multi 1 0K 0K 166960K 2 0 mrt 1 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 73 334K 334K 166960K 73 0 exec 0 0K 1K 166960K 428 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 229 177K 206K 166960K 4532 0 UVM aobj 7 2K 2K 166960K 7 0 pinsyscall 42 84K 112K 166960K 1362 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 14 0 NDP 9 0K 2K 166960K 27 0 temp 36 8671K 8738K 166960K 4853 0 kqueue 15 24K 30K 166960K 72 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 26 0 0 1 0 1 1 0 8 0 rtpcb 120 54 0 51 1 0 1 1 0 8 0 rtentry 176 114 0 25 6 0 6 6 0 8 0 unpcb 144 168 0 151 2 0 2 2 0 8 1 syncache 336 7 0 7 1 0 1 1 0 8 1 tcpcb 808 141 0 136 7 0 7 7 0 8 6 arp 128 18 0 4 1 0 1 1 0 8 0 ipq 40 1 0 0 1 0 1 1 0 8 0 ipqe 40 1 0 0 1 0 1 1 0 8 0 inpcb 384 310 0 300 8 0 8 8 0 8 6 nd6 144 27 0 8 1 0 1 1 0 8 0 kcovpl 48 10 0 4 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 472 0 105 30 0 30 30 0 8 2 art_table 32 473 0 105 4 0 4 4 0 8 0 art_node 16 113 0 32 1 0 1 1 0 8 0 sysvmsgpl 40 5 0 1 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 9 0 2 1 0 1 1 0 8 0 shmpl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 19 0 2 3 0 3 3 0 8 0 dino2pl 256 1811 0 299 95 0 95 95 0 8 0 ffsino 288 1811 0 299 109 0 109 109 0 8 0 nchpl 144 2236 0 556 63 0 63 63 0 8 0 uvmvnodes 80 1913 0 0 40 0 40 40 0 8 0 vnodes 216 1913 0 0 107 0 107 107 0 8 0 namei 1024 7149 0 7148 2 0 2 2 0 8 1 percpumem 16 48 0 2 1 0 1 1 0 8 0 kstatmem 264 24 0 4 2 0 2 2 0 8 0 scxspl 216 7595 0 7594 5 1 4 4 1 8 3 plimitpl 152 128 0 105 2 0 2 2 0 8 0 sigapl 424 600 0 548 8 0 8 8 0 8 0 knotepl 120 730 0 0 23 0 23 23 0 8 0 kqueuepl 224 90 0 77 1 0 1 1 0 8 0 pipepl 336 158 0 131 5 0 5 5 0 8 2 fdescpl 520 581 0 548 4 0 4 4 0 8 0 filepl 160 2725 0 2530 13 0 13 13 0 8 3 lockfpl 104 77 0 74 1 0 1 1 0 8 0 lockfspl 48 25 0 22 1 0 1 1 0 8 0 sessionpl 144 26 0 12 1 0 1 1 0 8 0 pgrppl 48 41 0 19 1 0 1 1 0 8 0 ucredpl 104 294 0 277 1 0 1 1 0 8 0 zombiepl 144 548 0 548 1 0 1 1 0 8 1 processpl 1208 600 0 548 5 0 5 5 0 8 0 procpl 656 892 0 833 7 0 7 7 0 8 1 sockpl 728 535 0 505 9 0 9 9 0 8 6 mcl64k 65536 3 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 109 0 0 14 0 14 14 0 8 0 mcl2k 2048 18 0 0 3 0 3 3 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 242 0 0 16 0 16 16 0 8 0 bufpl 280 5284 0 116 370 0 370 370 0 8 0 anonpl 32 9427 0 0 76 0 76 76 0 246 0 amapchunkpl 152 13982 0 13255 31 0 31 31 0 158 1 amappl16 200 2558 0 2535 15 4 11 14 0 8 8 amappl15 192 5 0 5 1 1 0 1 0 8 0 amappl14 184 115 0 104 1 0 1 1 0 8 0 amappl13 176 4 0 4 1 1 0 1 0 8 0 amappl12 168 1187 0 1155 2 0 2 2 0 8 0 amappl11 160 45 0 35 1 0 1 1 0 8 0 amappl10 152 5 0 5 1 1 0 1 0 8 0 amappl9 144 248 0 248 1 1 0 1 0 8 0 amappl8 136 22 0 20 1 0 1 1 0 8 0 amappl7 128 113 0 103 1 0 1 1 0 8 0 amappl6 120 177 0 174 1 0 1 1 0 8 0 amappl5 112 123 0 117 1 0 1 1 0 8 0 amappl4 104 296 0 280 1 0 1 1 0 8 0 amappl3 96 2384 0 2273 4 0 4 4 0 8 0 amappl2 88 628 0 572 2 0 2 2 0 8 0 amappl1 80 9268 0 8718 14 0 14 14 0 8 0 amappl 88 3831 0 3669 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 6 0 0 1 0 1 1 0 8 0 uaddrrnd 24 581 0 548 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 581 0 548 1 0 1 1 0 8 0 vmmpekpl 168 6700 0 6645 3 0 3 3 0 8 0 vmmpepl 168 44066 0 42175 100 0 100 100 0 357 6 vmsppl 480 580 0 548 7 1 6 6 0 8 1 rwobjpl 72 16953 0 14228 54 0 54 54 0 8 1 pdppl 4096 1169 0 1096 111 32 79 97 0 8 6 pvpl 32 28042 0 0 227 0 227 227 0 265 0 pmappl 256 580 0 548 4 1 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 407 0 35 12 0 12 12 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83382f2f) at panic+0x1e5 sys/kern/subr_prf.c:198 witness_warn(2,0,ffffffff8333d8ad) at witness_warn+0x850 witness_debugger sys/kern/subr_witness.c:2576 [inline] witness_warn(2,0,ffffffff8333d8ad) at witness_warn+0x850 sys/kern/subr_witness.c:1485 userret(ffff8000ffff0f80) at userret+0x3a4 sys/kern/kern_sig.c:2227 syscall(ffff8000327e4b70) at syscall+0x9c0 mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff8000327e4b70) at syscall+0x9c0 sys/arch/amd64/amd64/trap.c:600 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf94b3e00700, count: -6 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff8000299ddff0) 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(ffffffff839d6b00) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff839d6b00) at __mp_lock+0x192 sys/kern/kern_lock.c:144 vn_write(fffffd806c05b5e0,ffff8000327d2028,0) at vn_write+0x4e sys/kern/vfs_vnops.c:393 dofilewritev(ffff8000ffff1c50,c8,ffff8000327d2028,0,ffff8000327d20e0) at dofilewritev+0x23c sys/kern/sys_generic.c:380 sys_write(ffff8000ffff1c50,ffff8000327d2190,ffff8000327d20e0) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff8000327d2190) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff8000327d2190) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:579 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6a3141a70, count: 6 ddb{1}> trace x86_ipi_db(ffff8000299ddff0) 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(ffffffff839d6b00) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff839d6b00) at __mp_lock+0x192 sys/kern/kern_lock.c:144 vn_write(fffffd806c05b5e0,ffff8000327d2028,0) at vn_write+0x4e sys/kern/vfs_vnops.c:393 dofilewritev(ffff8000ffff1c50,c8,ffff8000327d2028,0,ffff8000327d20e0) at dofilewritev+0x23c sys/kern/sys_generic.c:380 sys_write(ffff8000ffff1c50,ffff8000327d2190,ffff8000327d20e0) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff8000327d2190) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff8000327d2190) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:579 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6a3141a70, count: -9