uvm_fault(0xfffffd800b027b70, 0x0, 0, 1) -> e fatal page fault in supervisor mode trap type 6 code 0 rip ffffffff831f9a38 cs 8 rflags 10207 cr2 0 cpl 0 rsp ffff80002a321ff0 gsbase 0xffff8000299edff0 kgsbase 0x0 panic: trap type 6, code=0, pc=ffffffff831f9a38 Starting stack trace... panic(ffffffff833c6b8d) at panic+0x1d0 sys/kern/subr_prf.c:229 kerntrap(ffff80002a321f40) at kerntrap+0x30b alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff800001667000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:593 dtclose(21e5f,81,2000,ffff80003a3fe2c0) at dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(21e5f,81,2000,ffff80003a3fe2c0) at dtclose+0x109 sys/dev/dt/dt_dev.c:239 spec_close(ffff80002a3220f0) at spec_close+0x466 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8063a81008,81,fffffd80097fb548,ffff80003a3fe2c0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806c2aa530,ffff80003a3fe2c0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806c2aa530,ffff80003a3fe2c0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806c2aa530,ffff80003a3fe2c0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806c2aa530,ffff80003a3fe2c0) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003a3fe2c0) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003a3fe2c0,b,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003a3fe2c0,ffff80002a322460,ffff80002a3223b0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002a322460) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a322460) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x772153530340, count: 242 End of stack trace. WA RNING: SPL NOT LOWERED ON SYSCALL 252 192 EXIT 0 4 Stopped at savectx+0xae: movl $0,%gs:0x688 TID PID UID PRFLAGS PFLAGS CPU COMMAND * 6282 3118 0 0 0x4000000 1 syz-executor 419045 65189 0 0 0x4000000 0 syz-executor savectx() at savectx+0xae end of kernel end trace frame: 0xf0175525790, 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(0xfffffd800b027b70, 0x0, 0, 1) -> e ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0xf0175525790, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80002c851d30 rbx 0 rdx 0 rcx 0xffff80002a284fa8 rax 0x35 r8 0xffff80002c851c60 r9 0x1 r10 0x978a61e571cb7427 r11 0x2bd8bc608a1c71b8 r12 0 r13 0 r14 0xffff80002a284fa8 r15 0 rip 0xffffffff818fb3ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80002c851cb0 ss 0x10 savectx+0xae: movl $0,%gs:0x688 ddb{1}> show proc PROC (syz-executor) tid=6282 pid=3118 tcnt=4 stat=onproc flags process=0 proc=4000000 runpri=50, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a285ca0,0xffff80002a285780 process=0xffff80002cbce1d8 user=0xffff80002c84c000, vmspace=0xfffffd806ee8c1f0 estcpu=36, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 3118 195940 92515 0 2 0 syz-executor * 3118 6282 92515 0 7 0x4000000 syz-executor 3118 383439 92515 0 3 0x4000080 fsleep syz-executor 3118 288540 92515 0 3 0x4000080 fsleep syz-executor 17627 31426 68948 0 2 0 syz-executor 17627 142031 68948 0 3 0x4000080 sbwait syz-executor 17627 264981 68948 0 3 0x4000080 sbufrcv syz-executor 17627 265502 68948 0 2 0x4000000 syz-executor 49797 150444 58933 0 2 0 syz-executor 49797 109813 58933 0 3 0x4000080 fsleep syz-executor 49797 453600 58933 0 3 0x4000080 fsleep syz-executor 65189 105517 66400 0 2 0 syz-executor 65189 419045 66400 0 7 0x4000000 syz-executor 65189 40724 66400 0 3 0x4000080 fsleep syz-executor 65189 247481 66400 0 3 0x4000080 fsleep syz-executor 40676 390864 39452 0 2 0 syz-executor 40676 144577 39452 0 3 0x4000080 fsleep syz-executor 40676 447962 39452 0 3 0x4000080 fsleep syz-executor 612 22236 86809 0 2 0xc80 syz-executor 612 55731 86809 0 3 0x4000080 ttyout syz-executor 37627 41546 19566 0 2 0xc80 syz-executor 37627 22379 19566 0 3 0x4000080 netcon syz-executor 37627 407123 19566 0 3 0x4000080 kqsel syz-executor 37627 187925 19566 0 3 0x4000080 kqsel syz-executor 37627 517543 19566 0 3 0x4000080 fsleep syz-executor 19566 293649 17039 0 2 0xc82 syz-executor 93131 266786 0 0 3 0x14200 acct acct 92515 54387 17039 0 2 0xc82 syz-executor 93845 339565 1 0 2 0x100083 getty 32170 193163 0 0 3 0x14280 nfsidl nfsio 82427 8200 0 0 3 0x14280 nfsidl nfsio 65684 83327 0 0 3 0x14280 nfsidl nfsio 26161 466202 0 0 3 0x14280 nfsidl nfsio 86809 140354 17039 0 2 0xc82 syz-executor 66400 431401 17039 0 2 0xc82 syz-executor 58933 317437 17039 0 2 0xc82 syz-executor 39452 3598 17039 0 2 0xc82 syz-executor 68948 458188 17039 0 2 0xc82 syz-executor 18725 194449 17039 0 2 0xc82 syz-executor 17039 16910 36966 0 3 0x82 kqread syz-executor 36966 57744 54322 0 3 0x10008a sigsusp ksh 54322 479577 23401 0 3 0x98 kqread sshd-session 23401 184547 47114 0 3 0x92 kqread sshd-session 47114 283386 1 0 3 0x88 kqread sshd 38290 180813 48637 74 3 0x1100092 bpf pflogd 48637 187225 1 0 3 0x80 sbwait pflogd 28282 398560 74143 73 3 0x1100090 kqread syslogd 74143 497427 1 0 3 0x100082 sbwait syslogd 90599 278576 1 0 3 0x100080 kqread resolvd 60748 508644 54992 77 3 0x100092 kqread dhcpleased 17879 94306 54992 77 3 0x100092 kqread dhcpleased 54992 355865 1 0 3 0x80 kqread dhcpleased 30635 405697 0 0 3 0x14200 bored smr 47566 352542 0 0 2 0x14200 zerothread 87414 158586 0 0 3 0x14200 aiodoned aiodoned 69538 208576 0 0 3 0x14200 syncer update 39673 320613 0 0 3 0x14200 cleaner cleaner 9208 407323 0 0 2 0x14200 reaper 70064 298333 0 0 3 0x14200 pgdaemon pagedaemon 20779 357291 0 0 3 0x14200 bored viomb 6864 366377 0 0 3 0x40014200 acpi0 acpi0 75042 144115 0 0 3 0x40014200 idle1 5143 157087 0 0 3 0x14200 bored softnet1 41801 32818 0 0 2 0x14200 softnet0 129 140243 0 0 2 0x14200 systqmp 89115 119874 0 0 3 0x14200 bored systq 30267 351800 0 0 3 0x14200 tmoslp softclockmp 93064 64816 0 0 3 0x40014200 tmoslp softclock 94052 93520 0 0 3 0x40014200 idle0 1 60136 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 17627 (syz-executor) thread 0xffff80003c436040 (142031) Process 65189 (syz-executor) thread 0xffff80003a3ff780 (419045) Process 40676 (syz-executor) thread 0xffff80002a284548 (390864) Process 9208 (reaper) thread 0xffff8000ffffd760 (407323) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10243 11082K 12419K 166960K 15121 0 pcb 17 16K 18K 166960K 551 0 rtable 182 12K 12K 166960K 981 0 pf 40 19K 67485K 166960K 510 0 ifaddr 29 6K 8K 166960K 245 0 ifgroup 51 2K 2K 166960K 465 0 sysctl 3 1K 9K 166960K 27 0 counters 66 36K 38K 166960K 466 0 ioctlops 0 0K 4K 166960K 2219 0 iov 1 4K 24K 166960K 171 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1522 96K 96K 166960K 4331 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 2K 9K 166960K 20 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 1K 166960K 261 0 dirhash 12 2K 3K 166960K 69 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 240K 166960K 3006 0 sigio 0 0K 0K 166960K 197 0 proc 73 115K 164K 166960K 1042 0 subproc 72 4K 4K 166960K 136 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 476 0 in_multi 50 4K 7K 166960K 333 0 ether_multi 1 0K 0K 166960K 55 0 mrt 1 0K 0K 166960K 35 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 247 1102K 1102K 166960K 247 0 exec 0 0K 1K 166960K 889 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 6 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 280 169K 178K 166960K 28704 0 UVM aobj 41 6K 6K 166960K 43 0 pinsyscall 43 86K 104K 166960K 4255 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 172 0 NDP 11 0K 1K 166960K 177 0 temp 90 8660K 8903K 166960K 134958 0 kqueue 16 26K 36K 166960K 600 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 120 518 0 514 7 6 1 3 0 8 0 rtentry 176 300 0 241 6 1 5 6 0 8 0 unpcb 144 1998 0 1977 16 15 1 6 0 8 0 syncache 336 7 0 7 5 5 0 1 0 8 0 tcpqe 32 6 0 6 3 3 0 1 0 8 0 tcpcb 736 1156 0 1149 18 17 1 10 0 8 0 arp 136 41 0 29 1 0 1 1 0 8 0 inpcb 328 3487 0 3476 38 36 2 18 0 8 0 nd6 152 58 0 47 2 1 1 2 0 8 0 pkpcb 40 29 0 29 5 4 1 1 0 8 1 kcovpl 48 15 0 7 1 0 1 1 0 8 0 mppekey 1024 13 0 13 5 5 0 1 0 8 0 ppxss 1192 146 0 146 3 2 1 1 0 8 1 pppxif 1504 29 0 29 8 7 1 1 0 8 1 pfstscr 40 12 0 11 1 0 1 1 0 8 0 pffrag 232 67 0 58 1 0 1 1 0 482 0 pffrnode 88 67 0 58 1 0 1 1 0 8 0 pffrent 40 123 0 114 1 0 1 1 0 8 0 pfosfp 40 1431 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1431 0 714 21 0 21 21 0 8 0 pfrktable 1344 4 0 2 1 0 1 1 0 8 0 pftag 88 3 0 1 2 1 1 1 0 8 0 pfstitem 24 127 0 88 1 0 1 1 0 8 0 pfstkey 128 148 0 109 3 0 3 3 0 8 0 pfstate 384 137 0 100 9 0 9 9 0 8 0 pfrule 1344 47 0 39 2 1 1 2 0 8 0 rttmr 136 6 0 6 4 4 0 1 0 8 0 art_heap8 4096 9 0 3 9 3 6 8 0 8 0 art_heap4 256 1352 0 1075 35 13 22 30 0 8 0 art_table 40 1361 0 1078 5 0 5 5 0 8 0 art_node 32 292 0 239 1 0 1 1 0 8 0 sysvmsgpl 40 23 0 11 1 0 1 1 0 8 0 semapl 112 257 0 247 1 0 1 1 0 8 0 shmpl 112 40 0 2 2 0 2 2 0 8 0 dirhash 1024 55 0 38 3 0 3 3 0 8 0 dino2pl 256 7350 0 5826 96 0 96 96 0 8 0 ffsino 296 7350 0 5826 118 0 118 118 0 8 0 nchpl 144 11301 0 9571 65 0 65 65 0 8 0 rtmask 32 20 0 20 5 4 1 1 0 8 1 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 40891 0 40891 6 5 1 2 0 8 1 percpumem 16 248 0 200 1 0 1 1 0 8 0 kstatmem 264 294 0 268 5 2 3 3 0 8 0 acpiwqpl 32 1 0 1 1 0 1 1 1 8 1 scsiplug 72 12 0 12 6 6 0 1 0 8 0 scxspl 216 62854 0 62854 14 13 1 8 1 8 1 plimitpl 152 814 0 795 1 0 1 1 0 8 0 sigapl 424 3275 0 3222 10 3 7 8 0 8 0 knotepl 120 791 0 0 24 0 24 24 0 8 0 kqueuepl 224 1318 0 1303 16 15 1 5 0 8 0 pipepl 344 441 0 411 7 4 3 6 0 8 0 fdescpl 528 3210 0 3178 3 0 3 3 0 8 0 filepl 160 23851 0 23621 39 26 13 21 0 8 1 lockfpl 104 1253 0 1239 3 1 2 3 0 8 0 lockfspl 48 520 0 507 1 0 1 1 0 8 0 sessionpl 144 34 0 25 1 0 1 1 0 8 0 pgrppl 48 150 0 133 1 0 1 1 0 8 0 ucredpl 104 4918 0 4904 1 0 1 1 0 8 0 zombiepl 144 3403 0 3402 1 0 1 1 0 8 0 processpl 1232 3275 0 3222 6 1 5 6 0 8 0 procpl 664 7972 0 7898 10 3 7 8 0 8 0 sosppl 176 20 0 20 7 6 1 1 0 8 1 sockpl 752 6141 0 6105 76 71 5 23 0 8 0 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 3 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 118 0 0 15 0 15 15 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 51 0 0 5 0 5 5 0 8 0 mtagpl 96 12 0 0 1 0 1 1 0 8 0 mbufpl 256 2912 0 0 180 0 180 180 0 8 0 bufpl 280 24993 0 18856 439 0 439 439 0 8 0 anonpl 32 11901 0 0 96 0 96 96 0 246 0 amapchunkpl 152 97846 0 97194 65 37 28 34 0 158 1 amappl16 200 10070 0 10016 69 60 9 28 0 8 0 amappl15 192 3 0 3 1 1 0 1 0 8 0 amappl14 184 41 0 41 1 1 0 1 0 8 0 amappl13 176 513 0 512 1 0 1 1 0 8 0 amappl12 168 3619 0 3576 3 0 3 3 0 8 0 amappl11 160 4 0 4 3 3 0 1 0 8 0 amappl10 152 53 0 39 1 0 1 1 0 8 0 amappl9 144 264 0 264 1 1 0 1 0 8 0 amappl8 136 26 0 24 1 0 1 1 0 8 0 amappl7 128 113 0 112 1 0 1 1 0 8 0 amappl6 120 389 0 375 1 0 1 1 0 8 0 amappl5 112 78 0 67 1 0 1 1 0 8 0 amappl4 104 466 0 437 1 0 1 1 0 8 0 amappl3 96 17324 0 17210 4 1 3 3 0 8 0 amappl2 88 3324 0 3245 2 0 2 2 0 8 0 amappl1 80 21408 0 20813 17 3 14 15 0 8 0 amappl 88 27352 0 27153 5 0 5 5 0 92 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 dma65536 65536 2 0 2 2 2 0 1 0 8 0 dma16384 16384 1 0 1 1 1 0 1 0 8 0 dma4096 4096 2 0 2 2 2 0 1 0 8 0 dma2048 2048 2 0 2 2 2 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 7 0 7 2 2 0 1 0 8 0 dma128 128 259 0 259 6 6 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 19 0 18 1 0 1 1 0 8 0 aobjpl 72 42 0 2 1 0 1 1 0 8 0 uaddrrnd 24 3210 0 3178 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3210 0 3178 1 0 1 1 0 8 0 vmmpekpl 168 24708 0 24634 5 1 4 4 0 8 0 vmmpepl 168 204953 0 202893 138 43 95 108 0 357 2 vmsppl 488 3209 0 3178 6 1 5 5 0 8 0 rwobjpl 80 57784 0 50813 152 4 148 150 0 8 0 pdppl 4096 6428 0 6356 126 54 72 86 0 8 0 pvpl 32 20977 0 0 170 0 170 170 0 265 0 pmappl 256 3209 0 3178 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 520 0 112 13 0 13 13 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff83877ff0) 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(ffffffff8389d020) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8389d020) at __mp_lock+0x192 sys/kern/kern_lock.c:165 intr_handler(ffff80002c816060,ffff80000006ac00) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:559 Xintr_ioapic_edge16_untramp() at Xintr_ioapic_edge16_untramp+0x18f __mp_lock(ffffffff8389d020) at __mp_lock+0x19e __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8389d020) at __mp_lock+0x19e sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff8389d020,1) 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 biowait(fffffd80667dd470) at biowait+0xc6 sys/kern/vfs_bio.c:1242 bwrite(fffffd80667dd470) at bwrite+0x2e7 sys/kern/vfs_bio.c:754 ffs_write(ffff80002c816380) at ffs_write+0x810 sys/ufs/ffs/ffs_vnops.c:377 VOP_WRITE(fffffd80742a9388,ffff80002c816538,7,fffffd80097fb548) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_write(fffffd806765d898,ffff80002c816538,0) at vn_write+0x1d3 sys/kern/vfs_vnops.c:408 end trace frame: 0xffff80002c816520, count: 0 ddb{0}> trace x86_ipi_db(ffffffff83877ff0) 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(ffffffff8389d020) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8389d020) at __mp_lock+0x192 sys/kern/kern_lock.c:165 intr_handler(ffff80002c816060,ffff80000006ac00) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:559 Xintr_ioapic_edge16_untramp() at Xintr_ioapic_edge16_untramp+0x18f __mp_lock(ffffffff8389d020) at __mp_lock+0x19e __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8389d020) at __mp_lock+0x19e sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff8389d020,1) 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 biowait(fffffd80667dd470) at biowait+0xc6 sys/kern/vfs_bio.c:1242 bwrite(fffffd80667dd470) at bwrite+0x2e7 sys/kern/vfs_bio.c:754 ffs_write(ffff80002c816380) at ffs_write+0x810 sys/ufs/ffs/ffs_vnops.c:377 VOP_WRITE(fffffd80742a9388,ffff80002c816538,7,fffffd80097fb548) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_write(fffffd806765d898,ffff80002c816538,0) at vn_write+0x1d3 sys/kern/vfs_vnops.c:408 dofilewritev(ffff80003a3ff780,5,ffff80002c816538,0,ffff80002c8165f0) at dofilewritev+0x242 sys/kern/sys_generic.c:380 sys_write(ffff80003a3ff780,ffff80002c8166a0,ffff80002c8165f0) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff80002c8166a0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002c8166a0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x31cd8ae6340, count: -18 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x688 savectx() at savectx+0xae end of kernel end trace frame: 0xf0175525790, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0xf0175525790, count: -1