uvm_fault(0xfffffd8062d175e8, 0x0, 0, 1) -> e fatal page fault in supervisor mode trap type 6 code 0 rip ffffffff81997a38 cs 8 rflags 10207 cr2 0 cpl 0 rsp ffff80003c031530 gsbase 0xffff8000299edff0 kgsbase 0x0 panic: trap type 6, code=0, pc=ffffffff81997a38 Starting stack trace... panic(ffffffff833a3685) at panic+0x1d0 sys/kern/subr_prf.c:229 kerntrap(ffff80003c031480) at kerntrap+0x30b alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff800001488000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:586 dtclose(11e5f,81,2000,ffff80003c458558) at dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(11e5f,81,2000,ffff80003c458558) at dtclose+0x109 sys/dev/dt/dt_dev.c:232 spec_close(ffff80003c031630) at spec_close+0x466 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805d06e648,81,fffffd80097fb548,ffff80003c458558) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806bb6f7b0,ffff80003c458558) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806bb6f7b0,ffff80003c458558) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806bb6f7b0,ffff80003c458558) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806bb6f7b0,ffff80003c458558) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003c458558) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003c458558,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003c458558,ffff80003c0319a0,ffff80003c0318f0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c0319a0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c0319a0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7dd224cc2250, count: 242 End of stack trace. WAR NING: SPL NOT LOWERED ON SYSCALL 83 -1659265728 EXIT 0 4 Stopped at savectx+0xae: movl $0,%gs:0x688 TID PID UID PRFLAGS PFLAGS CPU COMMAND *144850 52274 0 0 0 1 syz-executor 181615 59866 0 0x2 0x1 0 syz-executor savectx() at savectx+0xae end of kernel end trace frame: 0x7b21645a6b90, count: 14 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}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: uvm_fault(0xfffffd8062d175e8, 0x0, 0, 1) -> e ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7b21645a6b90, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80003c45f510 rbx 0 rdx 0 rcx 0xffff80003c458a88 rax 0x3c r8 0xffff80003c45f440 r9 0x1 r10 0x1ae9aff8705a6642 r11 0x1da043bfd1d19610 r12 0 r13 0 r14 0xffff80003c458a88 r15 0 rip 0xffffffff820ef3ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80003c45f490 ss 0x10 savectx+0xae: movl $0,%gs:0x688 ddb{1}> show proc PROC (syz-executor) tid=144850 pid=52274 tcnt=2 stat=onproc flags process=0 proc=0 runpri=86, usrpri=86, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c044fc8,0xffff80003c459a28 process=0xffff80003580d830 user=0xffff80003c45a000, vmspace=0xfffffd8062d177d0 estcpu=36, cpticks=3, pctcpu=0.0, user=1, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 58283 519604 12761 0 2 0 syz-executor 58283 214979 12761 0 2 0x4000000 syz-executor 86897 31042 59866 0 2 0 syz-executor 86897 443351 59866 0 3 0x4000080 fsleep syz-executor 38990 281887 85925 0 2 0 syz-executor 38990 286141 85925 0 3 0x4000080 fsleep syz-executor *52274 144850 96372 0 7 0 syz-executor 52274 296377 96372 0 2 0x4000000 syz-executor 83072 488294 89155 0 2 0xc80 syz-executor 83072 407741 89155 0 3 0x4000080 kqsel syz-executor 83072 440818 89155 0 3 0x4000000 smrbar syz-executor 83072 222736 89155 0 3 0x4000080 fsleep syz-executor 72856 49076 6251 0 3 0x3000 suspend syz-executor 72856 344389 6251 0 2 0x4081000 syz-executor 68683 294789 26622 0 3 0x3000 suspend syz-executor 68683 439171 26622 0 2 0x4081000 syz-executor 26622 401359 10441 0 3 0x82 wait syz-executor 96372 150283 10441 0 2 0xc82 syz-executor 4517 282313 0 0 3 0x14200 bored sosplice 89155 209980 10441 0 2 0xc82 syz-executor 12761 330948 10441 0 2 0xc82 syz-executor 85925 345551 10441 0 2 0xc82 syz-executor 59866 181615 10441 0 7 0x3 syz-executor 6251 505241 10441 0 2 0xc82 syz-executor 2570 308998 10441 0 2 0xc82 syz-executor 10441 494039 8240 0 3 0x82 kqread syz-executor 8240 157144 18204 0 3 0x10008a sigsusp ksh 18204 79567 39519 0 3 0x98 kqread sshd-session 39519 7983 84282 0 3 0x92 kqread sshd-session 19298 113360 1 0 2 0x100083 getty 84282 484380 1 0 3 0x88 kqread sshd 54825 147538 76126 74 3 0x1100092 bpf pflogd 76126 150898 1 0 3 0x80 sbwait pflogd 73100 15856 53460 73 3 0x1100090 kqread syslogd 53460 4253 1 0 3 0x100082 sbwait syslogd 59735 376282 1 0 3 0x100080 kqread resolvd 81592 73182 55981 77 3 0x100092 kqread dhcpleased 41742 284599 55981 77 3 0x100092 kqread dhcpleased 55981 33881 1 0 3 0x80 kqread dhcpleased 61087 394441 0 0 2 0x14200 smr 64959 98615 0 0 3 0x14200 pgzero zerothread 17611 368131 0 0 3 0x14200 aiodoned aiodoned 91533 226700 0 0 3 0x14200 syncer update 33239 230699 0 0 3 0x14200 cleaner cleaner 4166 50462 0 0 3 0x14200 reaper reaper 22039 108947 0 0 3 0x14200 pgdaemon pagedaemon 85132 481857 0 0 3 0x14200 bored viomb 64233 275820 0 0 3 0x40014200 acpi0 acpi0 3149 427660 0 0 3 0x40014200 idle1 63855 23536 0 0 3 0x14200 bored softnet7 45613 396295 0 0 3 0x14200 bored softnet6 11700 88550 0 0 3 0x14200 bored softnet5 88009 180109 0 0 3 0x14200 bored softnet4 86631 316611 0 0 3 0x14200 bored softnet3 5748 123591 0 0 3 0x14200 bored softnet2 26350 333279 0 0 3 0x14200 bored softnet1 69949 479666 0 0 3 0x14200 netlock softnet0 4461 353380 0 0 3 0x14200 smrbar systqmp 54549 101351 0 0 3 0x14200 bored systq 1273 70387 0 0 2 0x14200 softclockmp 82992 65088 0 0 3 0x40014200 netlock softclock 45878 283434 0 0 3 0x40014200 idle0 1 130686 0 0 3 0x80082 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 58283 (syz-executor) thread 0xffff8000ffff2a70 (214979) exclusive rrwlock inode r = 0 (0xfffffd806e20b598) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xa3 sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x18f sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x242 sys/kern/sys_generic.c:380 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 #9 Xsyscall+0x128 Process 83072 (syz-executor) thread 0xffff80003c458028 (440818) exclusive rwlock clonelk r = 0 (0xffffffff837cf078) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 if_clone_destroy+0x67 sys/net/if.c:-1 #3 ifioctl+0x59d sys/net/if.c:2066 #4 sys_ioctl+0x674 sys/kern/sys_generic.c:-1 #5 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 #6 Xsyscall+0x128 Process 72856 (syz-executor) thread 0xffff80003c459cb0 (344389) exclusive rrwlock inode r = 0 (0xfffffd806e0caca8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xa3 sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x18f sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x242 sys/kern/sys_generic.c:380 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 #9 Xsyscall+0x128 Process 68683 (syz-executor) thread 0xffff80003c459780 (439171) exclusive rrwlock inode r = 0 (0xfffffd806e0dddb8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xa3 sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x18f sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x242 sys/kern/sys_generic.c:380 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 #9 Xsyscall+0x128 Process 4461 (systqmp) thread 0xffff8000ffffe530 (353380) shared rwlock systqmp r = 0 (0xffffffff837c2268) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 taskq_thread+0x12a sys/kern/kern_task.c:442 #2 proc_trampoline+0x10 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10245 11075K 11286K 166960K 12367 0 pcb 17 15K 16K 166960K 294 0 rtable 177 10K 10K 166960K 748 0 pf 34 17K 131089K 166960K 251 0 ifaddr 34 6K 7K 166960K 130 0 ifgroup 51 2K 2K 166960K 244 0 sysctl 4 1K 9K 166960K 16 0 counters 66 36K 38K 166960K 302 0 ioctlops 0 0K 8K 166960K 1750 0 iov 0 0K 24K 166960K 140 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1397 88K 89K 166960K 2396 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 20 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 59 0 dirhash 12 2K 2K 166960K 45 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 240K 166960K 1394 0 sigio 0 0K 0K 166960K 18 0 proc 73 115K 164K 166960K 756 0 subproc 72 4K 4K 166960K 90 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 234 0 in_multi 74 5K 7K 166960K 184 0 ether_multi 1 0K 0K 166960K 29 0 mrt 2 0K 0K 166960K 8 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 229 1023K 1023K 166960K 229 0 exec 0 0K 1K 166960K 651 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 2 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 248 160K 173K 166960K 14300 0 UVM aobj 23 2K 2K 166960K 23 0 pinsyscall 43 86K 104K 166960K 2478 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 80 0 NDP 11 0K 2K 166960K 93 0 temp 79 8650K 8742K 166960K 64755 0 kqueue 14 22K 30K 166960K 277 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 26 0 0 1 0 1 1 0 8 0 rtpcb 120 138 0 135 1 0 1 1 0 8 0 rtentry 176 158 0 93 5 0 5 5 0 8 1 unpcb 144 1493 0 1475 17 15 2 8 0 8 1 syncache 336 3 0 3 1 1 0 1 0 8 0 tcpcb 736 539 0 534 7 6 1 7 0 8 0 arp 128 18 0 10 1 0 1 1 0 8 0 inpcb 328 1769 0 1761 19 12 7 12 0 8 5 nd6 144 23 0 10 1 0 1 1 0 8 0 pkpcb 40 13 0 13 3 2 1 1 0 8 1 kcovpl 48 10 0 2 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 1 0 1 0 8 0 ppxss 1192 92 0 92 2 1 1 1 0 8 1 pppxif 1504 9 0 9 3 3 0 1 0 8 0 pfstscr 40 1 0 1 1 1 0 1 0 8 0 pffrag 232 8 0 2 1 0 1 1 0 482 0 pffrnode 88 7 0 1 1 0 1 1 0 8 0 pffrent 40 15 0 9 1 0 1 1 0 8 0 pfosfp 40 1429 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1429 0 714 21 0 21 21 0 8 0 pfrktable 1344 11 0 11 3 3 0 1 0 8 0 pfanchor 1288 1 0 1 1 1 0 1 0 8 0 pftag 88 3 0 0 1 0 1 1 0 8 0 pfstitem 24 111 0 44 1 0 1 1 0 8 0 pfstkey 128 113 0 44 3 0 3 3 0 8 0 pfstate 384 108 0 43 8 0 8 8 0 8 0 pfrule 1344 57 0 51 2 1 1 2 0 8 0 rttmr 136 1 0 1 1 0 1 1 0 8 1 art_heap8 4096 4 0 0 4 0 4 4 0 8 0 art_heap4 256 697 0 337 30 5 25 28 0 8 2 art_table 40 701 0 337 5 0 5 5 0 8 0 art_node 32 155 0 96 1 0 1 1 0 8 0 sysvmsgpl 40 17 0 10 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 54 0 44 1 0 1 1 0 8 0 shmpl 112 20 0 0 1 0 1 1 0 8 0 dirhash 1024 40 0 23 3 0 3 3 0 8 0 dino2pl 256 3951 0 2440 96 1 95 96 0 8 0 ffsino 296 3951 0 2440 118 1 117 118 0 8 0 nchpl 144 5865 0 4166 64 0 64 64 0 8 0 rtmask 32 7 0 7 3 2 1 1 0 8 1 uvmvnodes 80 3978 0 0 82 0 82 82 0 8 0 vnodes 216 3978 0 0 221 0 221 221 0 8 0 namei 1024 20712 0 20712 2 1 1 1 0 8 1 percpumem 16 166 0 118 1 0 1 1 0 8 0 pfiaddrpl 120 3 0 3 1 1 0 1 0 8 0 kstatmem 264 150 0 124 3 0 3 3 0 8 0 scsiplug 72 1 0 1 1 1 0 1 0 8 0 scxspl 216 27812 0 27812 10 9 1 8 1 8 1 plimitpl 152 499 0 478 1 0 1 1 0 8 0 sigapl 424 1672 0 1617 9 1 8 9 0 8 0 knotepl 120 368 0 0 11 0 11 11 0 8 0 kqueuepl 224 503 0 491 5 4 1 5 0 8 0 pipepl 344 227 0 198 3 0 3 3 0 8 0 fdescpl 528 1624 0 1592 3 0 3 3 0 8 0 filepl 160 11006 0 10775 32 18 14 20 0 8 3 lockfpl 104 606 0 602 3 1 2 2 0 8 1 lockfspl 48 184 0 180 1 0 1 1 0 8 0 sessionpl 144 24 0 15 1 0 1 1 0 8 0 pgrppl 48 147 0 130 1 0 1 1 0 8 0 ucredpl 104 1856 0 1843 1 0 1 1 0 8 0 zombiepl 144 2189 0 2187 1 0 1 1 0 8 0 processpl 1232 1672 0 1617 6 1 5 6 0 8 0 procpl 664 3824 0 3760 9 2 7 9 0 8 0 sosppl 168 11 0 11 3 2 1 1 0 8 1 sockpl 752 3442 0 3413 65 54 11 24 0 8 7 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 mcl16k 16384 6 0 0 1 0 1 1 0 8 0 mcl12k 12288 3 0 0 1 0 1 1 0 8 0 mcl9k 9216 4 0 0 1 0 1 1 0 8 0 mcl8k 8192 6 0 0 1 0 1 1 0 8 0 mcl4k 4096 122 0 0 16 0 16 16 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 67 0 0 7 0 7 7 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 1849 0 0 116 0 116 116 0 8 0 bufpl 280 10302 0 4157 440 0 440 440 0 8 0 anonpl 32 10718 0 0 88 1 87 87 0 246 0 amapchunkpl 152 48765 0 48219 41 15 26 31 0 158 4 amappl16 200 4402 0 4234 30 19 11 18 0 8 2 amappl15 192 5 0 5 2 2 0 1 0 8 0 amappl14 184 113 0 101 1 0 1 1 0 8 0 amappl13 176 6 0 5 1 0 1 1 0 8 0 amappl12 168 2296 0 2264 3 1 2 2 0 8 0 amappl11 160 53 0 39 1 0 1 1 0 8 0 amappl10 152 6 0 6 2 2 0 1 0 8 0 amappl9 144 274 0 274 1 1 0 1 0 8 0 amappl8 136 26 0 22 1 0 1 1 0 8 0 amappl7 128 115 0 102 1 0 1 1 0 8 0 amappl6 120 197 0 193 1 0 1 1 0 8 0 amappl5 112 134 0 124 1 0 1 1 0 8 0 amappl4 104 294 0 275 1 0 1 1 0 8 0 amappl3 96 9590 0 9469 5 1 4 4 0 8 0 amappl2 88 670 0 605 2 0 2 2 0 8 0 amappl1 80 13097 0 12486 15 1 14 15 0 8 0 amappl 88 13397 0 13220 5 0 5 5 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 2 0 1 1 0 1 1 0 8 0 dma256 256 8 0 8 3 3 0 1 0 8 0 dma128 128 255 0 255 3 3 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 19 0 18 1 0 1 1 0 8 0 aobjpl 72 22 0 0 1 0 1 1 0 8 0 uaddrrnd 24 1624 0 1592 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1624 0 1592 1 0 1 1 0 8 0 vmmpekpl 168 14146 0 14103 3 0 3 3 0 8 0 vmmpepl 168 104977 0 102770 110 7 103 106 0 357 4 vmsppl 488 1623 0 1592 7 2 5 5 0 8 0 rwobjpl 80 32118 0 27022 104 0 104 104 0 8 0 pdppl 4096 3256 0 3184 110 38 72 86 0 8 0 pvpl 32 20737 0 0 167 0 167 167 0 265 0 pmappl 256 1623 0 1592 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 404 0 57 11 0 11 11 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff83787ff0) 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(ffffffff839a0500) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a0500) at __mp_lock+0x192 sys/kern/kern_lock.c:165 ktrsysret(ffff80002a2b9ca0,5b,0,ffff80002a35ef10) at ktrsysret+0xde ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrsysret(ffff80002a2b9ca0,5b,0,ffff80002a35ef10) at ktrsysret+0xde sys/kern/kern_ktrace.c:209 syscall(ffff80002a35efc0) at syscall+0xa50 mi_syscall_return sys/sys/syscall_mi.h:204 [inline] syscall(ffff80002a35efc0) at syscall+0xa50 sys/arch/amd64/amd64/trap.c:769 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x74060e8f6630, count: 8 ddb{0}> trace x86_ipi_db(ffffffff83787ff0) 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(ffffffff839a0500) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a0500) at __mp_lock+0x192 sys/kern/kern_lock.c:165 ktrsysret(ffff80002a2b9ca0,5b,0,ffff80002a35ef10) at ktrsysret+0xde ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrsysret(ffff80002a2b9ca0,5b,0,ffff80002a35ef10) at ktrsysret+0xde sys/kern/kern_ktrace.c:209 syscall(ffff80002a35efc0) at syscall+0xa50 mi_syscall_return sys/sys/syscall_mi.h:204 [inline] syscall(ffff80002a35efc0) at syscall+0xa50 sys/arch/amd64/amd64/trap.c:769 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x74060e8f6630, count: -7 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x688 savectx() at savectx+0xae end of kernel end trace frame: 0x7b21645a6b90, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7b21645a6b90, count: -1