uvm_fault(0xfffffd80635675e0, 0x0, 0, 1) -> e fatal page fault in supervisor mode trap type 6 code 0 rip ffffffff81f125f8 cs 8 rflags 10207 cr2 0 cpl 0 rsp ffff80002a3cd950 gsbase 0xffff8000299edff0 kgsbase 0x0 panic: trap type 6, code=0, pc=ffffffff81f125f8 Starting stack trace... panic(ffffffff833a2d6d) at panic+0x1d0 sys/kern/subr_prf.c:229 kerntrap(ffff80002a3cd8a0) at kerntrap+0x30b alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff80000167b000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:586 dtclose(11e5f,81,2000,ffff80003a8214f0) at dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(11e5f,81,2000,ffff80003a8214f0) at dtclose+0x109 sys/dev/dt/dt_dev.c:232 spec_close(ffff80002a3cda50) at spec_close+0x466 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806e0c1870,81,fffffd80097fb5b0,ffff80003a8214f0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806e4a4c90,ffff80003a8214f0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806e4a4c90,ffff80003a8214f0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806e4a4c90,ffff80003a8214f0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806e4a4c90,ffff80003a8214f0) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003a8214f0) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003a8214f0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003a8214f0,ffff80002a3cddc0,ffff80002a3cdd10) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002a3cddc0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3cddc0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x77d6b1c007d0, count: 242 End of stack trace. WARNING: SPL NOT LOWERED ON SYSCALL 83 -265612016 EXIT 0 4 Stopped at savectx+0xae: movl $0,%gs:0x688 TID PID UID PRFLAGS PFLAGS CPU COMMAND 523824 2213 0 0 0 0 syz-executor *313344 26775 0 0 0 1 syz-executor savectx() at savectx+0xae end of kernel end trace frame: 0x7e6d2ec36860, 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(0xfffffd80635675e0, 0x0, 0, 1) -> e ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7e6d2ec36860, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80002a39f6d0 rbx 0 rdx 0 rcx 0xffff800033409a10 rax 0x3b r8 0xffff80002a39f600 r9 0x1 r10 0x10161ade722a288d r11 0x8512098e1a5e0c55 r12 0 r13 0 r14 0xffff800033409a10 r15 0 rip 0xffffffff82c133ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80002a39f650 ss 0x10 savectx+0xae: movl $0,%gs:0x688 ddb{1}> show proc PROC (syz-executor) tid=313344 pid=26775 tcnt=2 stat=onproc flags process=0 proc=0 runpri=86, usrpri=86, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003a821a20,0xffff8000334094f0 process=0xffff80002a2c1cf8 user=0xffff80002a39a000, vmspace=0xfffffd806b7169a8 estcpu=36, cpticks=4, pctcpu=0.0, user=4, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 2213 523824 22613 0 7 0 syz-executor 2213 465164 22613 0 3 0x4000080 fsleep syz-executor 23186 381243 11414 0 2 0 syz-executor 23186 198343 11414 0 2 0x4000000 syz-executor *26775 313344 35161 0 7 0 syz-executor 26775 155923 35161 0 3 0x4000080 fsleep syz-executor 52694 163243 93978 0 2 0x82000 syz-executor 52694 179013 93978 0 3 0x4002000 suspend syz-executor 40124 19997 56651 0 2 0 syz-executor 40124 394862 56651 0 3 0x4000080 fsleep syz-executor 33459 87182 94855 0 3 0x90 nanoslp syz-executor 33459 368475 94855 0 3 0x4000090 kqsel syz-executor 33459 67456 94855 0 3 0x4000090 fsleep syz-executor 35290 89103 61686 0 3 0x3000 suspend syz-executor 35290 68884 61686 0 3 0x4081000 biowait syz-executor 35290 377791 61686 0 3 0x4081000 fltagain2 syz-executor 38727 318609 0 0 3 0x14200 acct acct 93978 303263 32480 0 3 0x82 nanoslp syz-executor 11414 221234 32480 0 3 0x82 nanoslp syz-executor 48236 417110 1 0 3 0x100083 ttyin getty 22613 344571 32480 0 3 0x82 nanoslp syz-executor 43970 324059 32480 0 3 0x82 nanoslp syz-executor 90253 398412 0 0 3 0x14200 bored sosplice 35161 498796 32480 0 3 0x82 nanoslp syz-executor 61686 479614 32480 0 3 0x82 nanoslp syz-executor 56651 157613 32480 0 3 0x82 nanoslp syz-executor 94855 120234 32480 0 3 0x82 nanoslp syz-executor 32480 131012 3402 0 3 0x82 kqread syz-executor 3402 414296 94412 0 3 0x10008a sigsusp ksh 94412 488299 33315 0 3 0x98 kqread sshd-session 33315 189946 34175 0 3 0x92 kqread sshd-session 34175 1960 1 0 3 0x88 kqread sshd 33020 266449 34884 74 3 0x1100092 bpf pflogd 34884 260203 1 0 3 0x80 sbwait pflogd 52838 285762 76873 73 3 0x1100090 kqread syslogd 76873 52034 1 0 3 0x100082 sbwait syslogd 30122 303715 1 0 3 0x100080 kqread resolvd 43394 96546 0 0 3 0x14200 bored smr 21189 269299 0 0 2 0x14200 zerothread 72120 494279 0 0 3 0x14200 aiodoned aiodoned 71653 284617 0 0 3 0x14200 syncer update 62353 84251 0 0 3 0x14200 cleaner cleaner 64036 49541 0 0 3 0x14200 reaper reaper 65425 82543 0 0 3 0x14200 pgdaemon pagedaemon 97615 104204 0 0 3 0x14200 bored viomb 8007 335685 0 0 3 0x40014200 acpi0 acpi0 36681 416672 0 0 3 0x40014200 idle1 93719 123616 0 0 3 0x14200 bored softnet7 42698 383725 0 0 3 0x14200 bored softnet6 52989 285836 0 0 3 0x14200 bored softnet5 19709 85757 0 0 3 0x14200 bored softnet4 56840 11269 0 0 3 0x14200 bored softnet3 69822 193728 0 0 3 0x14200 bored softnet2 67594 396711 0 0 3 0x14200 bored softnet1 76331 355686 0 0 3 0x14200 netlock softnet0 204 465266 0 0 2 0x40014200 systqmp 28480 381080 0 0 3 0x14200 bored systq 2487 405126 0 0 3 0x14200 tmoslp softclockmp 25240 311601 0 0 3 0x40014200 tmoslp softclock 95988 398809 0 0 3 0x40014200 idle0 1 254663 0 0 3 0x80082 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 35290 (syz-executor) thread 0xffff8000334082b8 (68884) Process 35290 (syz-executor) thread 0xffff80003c4a7a28 (377791) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10265 11104K 12443K 166960K 14482 0 pcb 17 18K 32K 166960K 1032 0 rtable 180 13K 14K 166960K 1016 0 pf 45 19K 131091K 166960K 487 0 ifaddr 36 7K 8K 166960K 247 0 ifgroup 73 3K 3K 166960K 490 0 sysctl 4 1K 9K 166960K 42 0 counters 74 37K 38K 166960K 682 0 ioctlops 0 0K 4K 166960K 2618 0 iov 0 0K 32K 166960K 382 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1548 97K 97K 166960K 4817 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 17 41K 41K 166960K 216 0 dirhash 12 2K 2K 166960K 90 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 106K 166960K 4355 0 sigio 0 0K 0K 166960K 125 0 proc 67 83K 180K 166960K 1171 0 subproc 72 4K 4K 166960K 121 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 2 0K 0K 166960K 691 0 in_multi 52 3K 7K 166960K 316 0 ether_multi 1 0K 0K 166960K 53 0 mrt 2 0K 0K 166960K 25 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 277 1235K 1235K 166960K 277 0 exec 0 0K 1K 166960K 1284 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 7 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 230 153K 191K 166960K 41673 0 UVM aobj 21 2K 2K 166960K 24 0 pinsyscall 37 74K 104K 166960K 5692 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 1K 166960K 391 0 NDP 15 0K 2K 166960K 188 0 temp 89 8652K 8908K 166960K 189882 0 kqueue 8 14K 31K 166960K 864 0 SYN cache 2 8K 16K 166960K 3 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 120 642 0 635 6 5 1 3 0 8 0 rtentry 176 311 0 255 5 0 5 5 0 8 0 unpcb 144 4476 0 4464 45 44 1 10 0 8 0 syncache 336 25 0 25 9 9 0 1 0 8 0 tcpqe 32 5 0 5 4 4 0 1 0 8 0 tcpcb 736 2065 0 2059 56 54 2 10 0 8 1 arp 136 33 0 26 1 0 1 1 0 8 0 inpcb 328 5769 0 5726 67 63 4 12 0 8 0 nd6 144 42 0 31 1 0 1 1 0 8 0 pkpcb 40 48 0 48 10 10 0 1 0 8 0 kcovpl 48 13 0 5 1 0 1 1 0 8 0 mppekey 1024 3 0 3 3 3 0 1 0 8 0 ppxss 1192 257 0 257 5 4 1 1 0 8 1 pppxif 1504 21 0 21 8 8 0 1 0 8 0 pfstscr 40 3 0 1 1 0 1 1 0 8 0 pffrag 232 60 0 50 1 0 1 1 0 482 0 pffrnode 88 32 0 22 1 0 1 1 0 8 0 pffrent 40 144 0 134 1 0 1 1 0 8 0 pfosfp 40 1429 0 1428 6 5 1 5 0 8 0 pfosfpen 112 1429 0 1428 21 20 1 21 0 8 0 pfrktable 1344 4 0 4 3 3 0 1 0 8 0 pfanchor 1288 1 0 0 1 0 1 1 0 8 0 pftag 88 3 0 1 1 0 1 1 0 8 0 pfstitem 24 280 0 160 1 0 1 1 0 8 0 pfstkey 128 281 0 162 4 0 4 4 0 8 0 pfstate 384 280 0 161 12 0 12 12 0 8 0 pfrule 1344 26 0 21 2 1 1 2 0 8 0 rttmr 136 3 0 3 3 3 0 1 0 8 0 art_heap8 4096 5 0 0 5 0 5 5 0 8 0 art_heap4 256 971 0 677 36 16 20 29 0 8 0 art_table 40 976 0 677 5 0 5 5 0 8 0 art_node 32 237 0 187 1 0 1 1 0 8 0 sysvmsgpl 40 19 0 11 1 0 1 1 0 8 0 semupl 112 3 0 3 3 3 0 1 0 8 0 semapl 112 209 0 194 1 0 1 1 0 8 0 shmpl 112 21 0 3 1 0 1 1 0 8 0 dirhash 1024 69 0 52 3 0 3 3 0 8 0 dino2pl 256 10064 0 8546 96 0 96 96 0 8 0 ffsino 296 10064 0 8546 118 0 118 118 0 8 0 nchpl 144 16220 0 15624 65 39 26 64 0 8 0 rtmask 32 38 0 38 12 12 0 1 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 58484 0 58484 6 5 1 2 0 8 1 percpumem 16 356 0 304 1 0 1 1 0 8 0 kstatmem 264 330 0 294 4 1 3 3 0 8 0 acpiwqpl 32 2 0 2 1 0 1 1 1 8 1 scsiplug 72 18 0 18 8 8 0 1 0 8 0 scxspl 216 103932 0 103931 16 15 1 8 1 8 0 plimitpl 152 1455 0 1438 1 0 1 1 0 8 0 sigapl 424 4678 0 4625 7 0 7 7 0 8 0 knotepl 120 935 0 0 24 0 24 24 0 8 0 kqueuepl 224 1752 0 1743 20 19 1 5 0 8 0 pipepl 344 641 0 613 12 9 3 6 0 8 0 fdescpl 528 4643 0 4614 3 0 3 3 0 8 0 filepl 160 36223 0 35908 63 49 14 25 0 8 0 lockfpl 104 1832 0 1830 3 2 1 3 0 8 0 lockfspl 48 667 0 665 2 1 1 2 0 8 0 sessionpl 144 50 0 42 1 0 1 1 0 8 0 pgrppl 48 142 0 126 1 0 1 1 0 8 0 ucredpl 104 7018 0 7006 1 0 1 1 0 8 0 zombiepl 144 5653 0 5651 1 0 1 1 0 8 0 processpl 1232 4678 0 4625 5 0 5 5 0 8 0 procpl 664 11900 0 11838 8 1 7 7 0 8 0 sosppl 168 39 0 38 11 10 1 1 0 8 0 sockpl 752 11208 0 11145 176 169 7 40 0 8 0 mcl64k 65536 17 0 0 3 0 3 3 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 5 0 0 1 0 1 1 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 119 0 0 15 0 15 15 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 62 0 0 7 0 7 7 0 8 0 mtagpl 96 5 0 0 1 0 1 1 0 8 0 mbufpl 256 416 0 0 19 0 19 19 0 8 0 bufpl 280 41400 0 35257 440 0 440 440 0 8 0 anonpl 32 15125 0 0 121 0 121 121 0 246 0 amapchunkpl 152 145463 0 144885 81 39 42 42 0 158 11 amappl16 200 13981 0 13874 74 56 18 33 0 8 0 amappl15 192 8 0 7 1 0 1 1 0 8 0 amappl14 184 171 0 162 1 0 1 1 0 8 0 amappl13 176 4 0 4 2 2 0 1 0 8 0 amappl12 168 5403 0 5374 2 0 2 2 0 8 0 amappl11 160 54 0 45 1 0 1 1 0 8 0 amappl10 152 4 0 4 1 1 0 1 0 8 0 amappl9 144 252 0 252 2 2 0 1 0 8 0 amappl8 136 25 0 22 1 0 1 1 0 8 0 amappl7 128 148 0 138 1 0 1 1 0 8 0 amappl6 120 259 0 255 1 0 1 1 0 8 0 amappl5 112 154 0 147 1 0 1 1 0 8 0 amappl4 104 396 0 377 1 0 1 1 0 8 0 amappl3 96 25861 0 25773 3 0 3 3 0 8 0 amappl2 88 5078 0 5013 3 0 3 3 0 8 0 amappl1 80 30473 0 29963 18 3 15 16 0 8 0 amappl 88 39974 0 39803 5 0 5 5 0 92 0 dma65536 65536 2 0 2 1 1 0 1 0 8 0 dma32768 32768 2 0 2 2 2 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 2 0 2 1 1 0 1 0 8 0 dma256 256 8 0 8 3 3 0 1 0 8 0 dma128 128 324 0 324 7 7 0 1 0 8 0 dma64 64 8 0 8 3 3 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 20 0 19 1 0 1 1 0 8 0 aobjpl 72 23 0 3 1 0 1 1 0 8 0 uaddrrnd 24 4643 0 4614 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4643 0 4614 1 0 1 1 0 8 0 vmmpekpl 168 37290 0 37230 3 0 3 3 0 8 0 vmmpepl 168 294551 0 292722 135 39 96 115 0 357 0 vmsppl 488 4642 0 4614 6 1 5 5 0 8 0 rwobjpl 80 79837 0 73015 159 15 144 150 0 8 0 pdppl 4096 9294 0 9228 158 92 66 86 0 8 0 pvpl 32 22505 0 0 182 1 181 181 0 265 0 pmappl 256 4642 0 4614 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 431 0 188 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff837e3ff0) 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(ffffffff839a9148) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a9148) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(2) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(2) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsofttty() at Xsofttty+0x27 __mp_lock(ffffffff839a9148) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a9148) at __mp_lock+0x192 sys/kern/kern_lock.c:165 intr_handler(ffff80003c4453d0,ffff800000079a80) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:559 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f __mp_lock(ffffffff839a9148) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a9148) at __mp_lock+0x192 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff839a9148,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 rw_do_enter_write(ffffffff83933e88,0) at rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298 end trace frame: 0xffff80003c445650, count: 0 ddb{0}> trace x86_ipi_db(ffffffff837e3ff0) 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(ffffffff839a9148) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a9148) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(2) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(2) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsofttty() at Xsofttty+0x27 __mp_lock(ffffffff839a9148) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a9148) at __mp_lock+0x192 sys/kern/kern_lock.c:165 intr_handler(ffff80003c4453d0,ffff800000079a80) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:559 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f __mp_lock(ffffffff839a9148) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff839a9148) at __mp_lock+0x192 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff839a9148,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 rw_do_enter_write(ffffffff83933e88,0) at rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298 vm_map_lock_ln(ffffffff83933da0,0,0) at vm_map_lock_ln+0x12e sys/uvm/uvm_map.c:5168 uvm_map(ffffffff83933da0,ffff80003c445790,6000,0,ffffffffffffffff,0,b8174a20981229a6) at uvm_map+0x404 sys/uvm/uvm_map.c:1021 km_alloc(6000,ffffffff8347e198,ffffffff83547e98,ffffffff83547f10) at km_alloc+0x20d sys/uvm/uvm_km.c:746 uvm_uarea_alloc() at uvm_uarea_alloc+0x52 sys/uvm/uvm_glue.c:-1 thread_fork(ffff800033408fb0,a85d88f99b0,a8542c2aa00,a8542c2aa30,ffff80003c445980) at thread_fork+0x170 sys/kern/kern_fork.c:562 sys___tfork(ffff800033408fb0,ffff80003c445a30,ffff80003c445980) at sys___tfork+0x1b6 sys/kern/kern_fork.c:141 syscall(ffff80003c445a30) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c445a30) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7da339e52ae0, count: -22 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x688 savectx() at savectx+0xae end of kernel end trace frame: 0x7e6d2ec36860, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7e6d2ec36860, count: -1