witness: lock order reversal: 1st 0xffff8000013264a0 sbufsnd (&so->so_snd.sb_lock) 2nd 0xfffffd806a0042c0 inode (&ip->i_lock) lock order [1] sbufsnd (&so->so_snd.sb_lock) -> [2] inode (&ip->i_lock) lock order data 0xffffffff830be9a1 -> 0xffffffff8306b4aa is missing lock order [2] inode (&ip->i_lock) -> [3] sbufrcv (&so->so_rcv.sb_lock) #0 rw_enter+0x122 #1 sblock+0xb7 sys/kern/uipc_socket2.c:549 #2 soreceive+0x295 sys/kern/uipc_socket.c:945 #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+0xf6 sys/kern/vfs_vnops.c:525 #10 sys_ioctl+0x67c #11 syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:178 [inline] #11 syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 #12 Xsyscall+0x128 lock order [3] sbufrcv (&so->so_rcv.sb_lock) -> [1] sbufsnd (&so->so_snd.sb_lock) #0 rw_enter+0x122 #1 sblock+0xb7 sys/kern/uipc_socket2.c:549 #2 sosplice+0x3f4 sys/kern/uipc_socket.c:1454 #3 sys_setsockopt+0x2ba sys/kern/uipc_syscalls.c:1228 #4 syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:178 [inline] #4 syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 #5 Xsyscall+0x128 Stopped at db_enter+0x25: addq $0x8,%rsp ddb{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic the kernel did not panic ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:437 witness_checkorder(fffffd806a0042c0,9,0) at witness_checkorder+0x1047 rw_enter(fffffd806a0042b0,1) at rw_enter+0x122 rrw_enter(fffffd806a0042b0,1) at rrw_enter+0xbe sys/kern/kern_rwlock.c:464 VOP_LOCK(fffffd805f7dea20,2001) at VOP_LOCK+0xa6 sys/kern/vfs_vops.c:524 vn_lock(fffffd805f7dea20,2001) at vn_lock+0xa4 sys/kern/vfs_vnops.c:564 vfs_lookup(ffff8000339a4218) at vfs_lookup+0x109 sys/kern/vfs_lookup.c:418 namei(ffff8000339a4218) at namei+0x7aa sys/kern/vfs_lookup.c:250 unp_connect(ffff8000013262f8,fffffd806842c000,ffff8000ffff0cd0) at unp_connect+0x27d sys/kern/uipc_usrreq.c:868 uipc_dgram_send(ffff8000013262f8,fffffd806c57c500,fffffd806842c000,0) at uipc_dgram_send+0x131 sys/kern/uipc_usrreq.c:607 sosend(ffff8000013262f8,fffffd806842c000,ffff8000339a44a8,0,0,0) at sosend+0xa40 sendit(ffff8000ffff0cd0,6,ffff8000339a4620,0,ffff8000339a46e0) at sendit+0x721 sys/kern/uipc_syscalls.c:786 sys_sendmsg(ffff8000ffff0cd0,ffff8000339a4790,ffff8000339a46e0) at sys_sendmsg+0x246 sys/kern/uipc_syscalls.c:604 syscall(ffff8000339a4790) at syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:178 [inline] syscall(ffff8000339a4790) at syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2049f5d2ee0, count: -15 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff8000339a3e70 rbx 0xfffffd80042c2f10 rdx 0 rcx 0xffff8000ffff0cd0 rax 0xffffffff8349fff0 cpu_info_full_primary+0x1ff0 r8 0xffff8000339a3d50 r9 0x8080808080808080 r10 0xdb59fc38865739bf r11 0x75dcb75b00a402b3 r12 0 r13 0xfffffd8003adae00 r14 0x3 r15 0xffffffff rip 0xffffffff81610e15 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff8000339a3e60 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=431870 pid=46509 tcnt=4 stat=onproc flags process=10 proc=4000000 runpri=32, usrpri=83, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000fffe87d0,0xffff8000fffe9998 process=0xffff8000fffe4000 user=0xffff80003399f000, vmspace=0xfffffd806a02c3a8 estcpu=33, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 19158 248003 57031 0 2 0 syz-executor 73538 284591 5848 0 2 0 syz-executor 26498 440464 56847 60928 7 0x10 syz-executor 26498 336554 56847 60928 3 0x4000090 kqsel syz-executor 60967 484126 43044 0 2 0 syz-executor 46509 411554 33990 0 2 0x10 syz-executor 46509 283025 33990 0 3 0x4000090 rest syz-executor *46509 431870 33990 0 7 0x4000010 syz-executor 46509 513594 33990 0 3 0x4000090 fsleep syz-executor 70515 245909 25333 0 3 0x80 nanoslp syz-executor 70515 97911 25333 0 3 0x4000080 ttyout syz-executor 70515 191099 25333 0 3 0x4000080 fsleep syz-executor 70515 382928 25333 0 3 0x4000080 fsleep syz-executor 89379 370698 24074 0 3 0x80 nanoslp syz-executor 89379 175389 24074 0 3 0x4000080 kqsel syz-executor 89379 120592 24074 0 3 0x4000080 fsleep syz-executor 78269 376509 0 0 3 0x14200 acct acct 43044 106778 19592 0 3 0x82 nanoslp syz-executor 72439 8511 1 0 3 0x100083 ttyin getty 98102 92621 0 0 3 0x14280 nfsidl nfsio 83651 353615 0 0 3 0x14280 nfsidl nfsio 39792 89881 0 0 3 0x14280 nfsidl nfsio 18676 360056 0 0 3 0x14280 nfsidl nfsio 21053 206200 0 0 3 0x14280 nfsidl nfsio 33037 506474 0 0 3 0x14280 nfsidl nfsio 86101 218877 0 0 3 0x14280 nfsidl nfsio 81738 435813 0 0 3 0x14280 nfsidl nfsio 43661 434600 0 0 3 0x14280 nfsidl nfsio 21670 503550 0 0 3 0x14280 nfsidl nfsio 5046 133210 0 0 3 0x14280 nfsidl nfsio 24100 457384 0 0 3 0x14280 nfsidl nfsio 82637 465177 0 0 3 0x14280 nfsidl nfsio 65392 36696 0 0 3 0x14280 nfsidl nfsio 11271 359190 0 0 3 0x14280 nfsidl nfsio 20987 295210 0 0 3 0x14280 nfsidl nfsio 35558 179488 0 0 3 0x14280 nfsidl nfsio 28808 29237 0 0 3 0x14280 nfsidl nfsio 72034 276412 0 0 3 0x14280 nfsidl nfsio 95239 42828 0 0 3 0x14280 nfsidl nfsio 77045 81046 0 0 3 0x14200 bored sosplice 56847 178394 19592 0 3 0x82 nanoslp syz-executor 35745 417251 19592 0 2 0x2 syz-executor 24074 367257 19592 0 3 0x82 nanoslp syz-executor 57031 256914 19592 0 3 0x82 nanoslp syz-executor 33990 99507 19592 0 3 0x82 nanoslp syz-executor 25333 141537 19592 0 3 0x82 nanoslp syz-executor 5848 130190 19592 0 3 0x82 nanoslp syz-executor 19592 488085 23140 0 3 0x82 kqread syz-executor 23140 421453 20533 0 3 0x10008a sigsusp ksh 20533 149333 39232 0 3 0x98 kqread sshd-session 39232 492298 19004 0 3 0x92 kqread sshd-session 19004 387712 1 0 3 0x88 kqread sshd 51924 185979 51171 74 3 0x1100092 bpf pflogd 51171 374863 1 0 3 0x80 sbwait pflogd 70696 258805 11690 73 3 0x1100090 kqread syslogd 11690 194896 1 0 3 0x100082 sbwait syslogd 9592 383779 1 0 3 0x100080 kqread resolvd 99365 362574 28272 77 3 0x100092 kqread dhcpleased 44485 437578 28272 77 3 0x100092 kqread dhcpleased 28272 235639 1 0 3 0x80 kqread dhcpleased 15559 296635 0 0 3 0x14200 bored smr 57339 24101 0 0 2 0x14200 zerothread 61240 54766 0 0 3 0x14200 aiodoned aiodoned 29175 336426 0 0 3 0x14200 syncer update 1051 31958 0 0 3 0x14200 cleaner cleaner 63133 237948 0 0 3 0x14200 reaper reaper 26204 491455 0 0 3 0x14200 pgdaemon pagedaemon 51173 41088 0 0 3 0x14200 bored viomb 3478 67638 0 0 3 0x40014200 acpi0 acpi0 51344 401652 0 0 3 0x40014200 idle1 65220 462538 0 0 3 0x14200 bored softnet3 66011 27640 0 0 3 0x14200 bored softnet2 62745 459145 0 0 3 0x14200 bored softnet1 66595 105342 0 0 3 0x14200 bored softnet0 86399 355939 0 0 3 0x14200 bored systqmp 27271 491650 0 0 3 0x14200 bored systq 5373 106515 0 0 3 0x14200 tmoslp softclockmp 92034 301842 0 0 3 0x40014200 tmoslp softclock 58101 512549 0 0 3 0x40014200 idle0 1 319497 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 46509 (syz-executor) thread 0xffff8000ffff0cd0 (431870) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8359d538) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 unp_connect+0x26c sys/kern/uipc_usrreq.c:868 #2 uipc_dgram_send+0x131 sys/kern/uipc_usrreq.c:607 #3 sosend+0xa40 #4 sendit+0x721 sys/kern/uipc_syscalls.c:786 #5 sys_sendmsg+0x246 sys/kern/uipc_syscalls.c:604 #6 syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:178 [inline] #6 syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 #7 Xsyscall+0x128 exclusive rwlock sbufsnd r = 0 (0xffff8000013264a0) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 rw_enter+0x41b sys/kern/kern_rwlock.c:309 #2 sblock+0xb7 sys/kern/uipc_socket2.c:549 #3 sosend+0x2ff sys/kern/uipc_socket.c:681 #4 sendit+0x721 sys/kern/uipc_syscalls.c:786 #5 sys_sendmsg+0x246 sys/kern/uipc_syscalls.c:604 #6 syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:178 [inline] #6 syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 #7 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10238 11265K 11500K 166960K 12414 0 pcb 17 16K 18K 166960K 130 0 rtable 223 6K 7K 166960K 992 0 pf 37 18K 18K 166960K 63 0 ifaddr 44 7K 8K 166960K 66 0 ifgroup 60 2K 2K 166960K 81 0 sysctl 3 0K 0K 166960K 3 0 counters 66 36K 36K 166960K 80 0 ioctlops 0 0K 4K 166960K 1601 0 iov 0 0K 12K 166960K 49 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1423 89K 90K 166960K 2047 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 5K 9K 166960K 22 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 27 0 dirhash 12 2K 2K 166960K 24 0 ACPI 1690 195K 286K 166960K 12468 0 file desc 17 61K 97K 166960K 935 0 sigio 0 0K 0K 166960K 25 0 proc 72 91K 128K 166960K 646 0 subproc 104 6K 6K 166960K 117 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 1 0K 0K 166960K 103 0 in_multi 95 7K 7K 166960K 165 0 ether_multi 1 0K 0K 166960K 5 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 235 1049K 1049K 166960K 235 0 exec 0 0K 1K 166960K 559 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 228 72K 87K 166960K 10596 0 UVM aobj 28 2K 2K 166960K 30 0 pinsyscall 42 84K 106K 166960K 2104 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 34 0 NDP 13 0K 2K 166960K 42 0 temp 52 6821K 6942K 166960K 28994 0 kqueue 14 22K 28K 166960K 138 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 24 0 0 1 0 1 1 0 8 0 rtpcb 120 108 0 104 2 1 1 2 0 8 0 rtentry 112 345 0 242 4 0 4 4 0 8 0 unpcb 144 1052 0 1032 7 6 1 7 0 8 0 syncache 336 11 0 11 5 5 0 1 0 8 0 tcpqe 32 3 0 3 1 1 0 1 0 8 0 tcpcb 808 245 0 237 6 5 1 4 0 8 0 arp 120 92 0 72 1 0 1 1 0 8 0 inpcb 336 1117 0 1101 15 13 2 9 0 8 0 nd6 136 32 0 6 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 1 0 1 0 8 0 kcovpl 48 9 0 1 1 0 1 1 0 8 0 ppxss 1168 4 0 4 2 2 0 1 0 8 0 pffrag 232 5 0 0 1 0 1 1 0 482 0 pffrnode 88 5 0 0 1 0 1 1 0 8 0 pffrent 40 6 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 pfstitem 24 59 0 19 1 0 1 1 0 8 0 pfstkey 128 59 0 19 2 0 2 2 0 8 0 pfstate 376 59 0 19 5 0 5 5 0 8 0 pfrule 1344 21 0 15 2 0 2 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 852 0 406 31 2 29 31 0 8 0 art_table 32 853 0 406 4 0 4 4 0 8 0 art_node 16 343 0 254 1 0 1 1 0 8 0 sysvmsgpl 40 5 0 2 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 25 0 15 1 0 1 1 0 8 0 shmpl 112 27 0 2 1 0 1 1 0 8 0 dirhash 1024 25 0 8 3 0 3 3 0 8 0 dino2pl 256 3071 0 1567 95 0 95 95 0 8 0 ffsino 272 3071 0 1567 102 1 101 102 0 8 0 nchpl 144 4340 0 2651 64 0 64 64 0 8 0 uvmvnodes 80 3528 0 0 72 0 72 72 0 8 0 vnodes 216 3528 0 0 196 0 196 196 0 8 0 namei 1024 15192 0 15191 6 5 1 3 0 8 0 percpumem 16 54 0 7 1 0 1 1 0 8 0 kstatmem 264 40 0 14 2 0 2 2 0 8 0 scsiplug 72 3 0 3 3 3 0 1 0 8 0 scxspl 216 12769 0 12769 9 8 1 8 1 8 1 plimitpl 152 356 0 339 1 0 1 1 0 8 0 sigapl 424 1274 0 1202 9 0 9 9 0 8 0 futexpl 64 12131 0 12127 1 0 1 1 0 8 0 knotepl 120 553 0 0 17 0 17 17 0 8 0 kqueuepl 216 271 0 259 3 2 1 3 0 8 0 pipepl 320 230 0 203 6 3 3 6 0 8 0 fdescpl 496 1231 0 1200 6 1 5 6 0 8 0 filepl 152 8470 0 8215 21 10 11 18 0 8 1 lockfpl 104 249 0 247 1 0 1 1 0 8 0 lockfspl 48 113 0 111 1 0 1 1 0 8 0 sessionpl 144 32 0 23 1 0 1 1 0 8 0 pgrppl 48 182 0 165 1 0 1 1 0 8 0 ucredpl 104 1264 0 1248 1 0 1 1 0 8 0 zombiepl 144 1232 0 1231 3 2 1 1 0 8 0 processpl 1160 1274 0 1202 6 0 6 6 0 8 0 procpl 648 2664 0 2583 8 0 8 8 0 8 0 srpgc 96 4 0 4 2 2 0 1 0 8 0 sosppl 168 9 0 9 2 2 0 1 0 8 0 sockpl 664 2354 0 2316 29 24 5 17 0 8 0 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 154 0 0 20 0 20 20 0 8 0 mcl2k 2048 21 0 0 3 0 3 3 0 8 0 mtagpl 96 21 0 0 1 0 1 1 0 8 0 mbufpl 256 367 0 0 22 0 22 22 0 8 0 bufpl 280 3838 0 100 267 0 267 267 0 8 0 anonpl 24 238794 0 235431 71 38 33 70 0 185 0 amapchunkpl 152 34336 0 33873 30 8 22 28 0 158 0 amappl16 200 6133 0 6104 40 36 4 27 0 8 0 amappl15 192 11 0 11 1 1 0 1 0 8 0 amappl14 184 144 0 132 1 0 1 1 0 8 0 amappl13 176 32 0 32 1 1 0 1 0 8 0 amappl12 168 1911 0 1882 4 2 2 3 0 8 0 amappl11 160 72 0 58 1 0 1 1 0 8 0 amappl10 152 12 0 12 1 1 0 1 0 8 0 amappl9 144 134 0 134 1 1 0 1 0 8 0 amappl8 136 98 0 95 1 0 1 1 0 8 0 amappl7 128 121 0 109 1 0 1 1 0 8 0 amappl6 120 180 0 178 1 0 1 1 0 8 0 amappl5 112 159 0 147 1 0 1 1 0 8 0 amappl4 104 354 0 334 1 0 1 1 0 8 0 amappl3 96 6465 0 6376 3 0 3 3 0 8 0 amappl2 88 1588 0 1505 3 0 3 3 0 8 0 amappl1 80 12144 0 11585 16 2 14 16 0 8 0 amappl 88 10102 0 9938 5 0 5 5 0 92 0 dma32768 32768 1 0 1 1 1 0 1 0 8 0 dma16384 16384 1 0 1 1 1 0 1 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 dma512 512 1 0 1 1 1 0 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 29 0 2 1 0 1 1 0 8 0 uaddrrnd 24 1231 0 1200 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1231 0 1200 1 0 1 1 0 8 0 vmmpekpl 168 12143 0 12102 3 0 3 3 0 8 0 vmmpepl 168 85262 0 83418 104 15 89 102 0 357 0 vmsppl 448 1230 0 1200 6 2 4 5 0 8 0 rwobjpl 56 30862 0 26382 65 1 64 64 0 8 0 pdppl 4096 2469 0 2400 125 54 71 87 0 8 2 pvpl 32 18620 0 0 151 0 151 151 0 265 0 pmappl 248 1230 0 1200 3 0 3 3 0 8 0 extentpl 40 55 0 38 1 0 1 1 0 8 0 phpool 112 451 0 94 11 0 11 11 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:437 witness_checkorder(fffffd806a0042c0,9,0) at witness_checkorder+0x1047 rw_enter(fffffd806a0042b0,1) at rw_enter+0x122 rrw_enter(fffffd806a0042b0,1) at rrw_enter+0xbe sys/kern/kern_rwlock.c:464 VOP_LOCK(fffffd805f7dea20,2001) at VOP_LOCK+0xa6 sys/kern/vfs_vops.c:524 vn_lock(fffffd805f7dea20,2001) at vn_lock+0xa4 sys/kern/vfs_vnops.c:564 vfs_lookup(ffff8000339a4218) at vfs_lookup+0x109 sys/kern/vfs_lookup.c:418 namei(ffff8000339a4218) at namei+0x7aa sys/kern/vfs_lookup.c:250 unp_connect(ffff8000013262f8,fffffd806842c000,ffff8000ffff0cd0) at unp_connect+0x27d sys/kern/uipc_usrreq.c:868 uipc_dgram_send(ffff8000013262f8,fffffd806c57c500,fffffd806842c000,0) at uipc_dgram_send+0x131 sys/kern/uipc_usrreq.c:607 sosend(ffff8000013262f8,fffffd806842c000,ffff8000339a44a8,0,0,0) at sosend+0xa40 sendit(ffff8000ffff0cd0,6,ffff8000339a4620,0,ffff8000339a46e0) at sendit+0x721 sys/kern/uipc_syscalls.c:786 sys_sendmsg(ffff8000ffff0cd0,ffff8000339a4790,ffff8000339a46e0) at sys_sendmsg+0x246 sys/kern/uipc_syscalls.c:604 syscall(ffff8000339a4790) at syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:178 [inline] syscall(ffff8000339a4790) at syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2049f5d2ee0, count: -15 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp ddb{1}> trace x86_ipi_db(ffff800029b7bff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:393 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(ffffffff8359d330) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff8359d330) at __mp_lock+0x192 sys/kern/kern_lock.c:144 syscall(ffff8000371e6950) at syscall+0xad6 mi_syscall sys/sys/syscall_mi.h:178 [inline] syscall(ffff8000371e6950) at syscall+0xad6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x78e4781bc250, count: -6