uvm_fault(0xfffffd805f202b68, 0x0, 0, 1) -> e fatal page fault in supervisor mode trap type 6 code 0 rip ffffffff82a83cd0 cs 8 rflags 10207 cr2 0 cpl 0 rsp ffff80002a2f9e00 gsbase 0xffff8000299edff0 kgsbase 0x0 panic: trap type 6, code=0, pc=ffffffff82a83cd0 Starting stack trace... panic(ffffffff8333e810) at panic+0x1d0 sys/kern/subr_prf.c:229 kerntrap(ffff80002a2f9d50) at kerntrap+0x29b sys/arch/amd64/amd64/trap.c:327 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff800001496000) at dt_ioctl_record_stop+0xf0 sys/dev/dt/dt_dev.c:579 dtclose(21e5f,81,2000,ffff80002a2b5208) at dtclose+0x105 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(21e5f,81,2000,ffff80002a2b5208) at dtclose+0x105 sys/dev/dt/dt_dev.c:232 spec_close(ffff80002a2f9f00) at spec_close+0x45f sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8060212628,81,fffffd807f7d2548,ffff80002a2b5208) at VOP_CLOSE+0x133 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806c435c08,ffff80002a2b5208) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806c435c08,ffff80002a2b5208) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806c435c08,ffff80002a2b5208) at fdrop+0x126 sys/kern/kern_descrip.c:1265 closef(fffffd806c435c08,ffff80002a2b5208) at closef+0x192 sys/kern/kern_descrip.c:1249 fdfree(ffff80002a2b5208) at fdfree+0x116 sys/kern/kern_descrip.c:1181 exit1(ffff80002a2b5208,0,0,1) at exit1+0x58f sys/kern/kern_exit.c:214 sys_exit(ffff80002a2b5208,ffff80002a2fa270,ffff80002a2fa1c0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002a2fa270) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a2fa270) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ad53ea262d0, count: 242 End of stack trace. WARNING: SPL NOT LOWERED ON SYSCALL 74 -383201280 EXIT 0 4 Stopped at savectx+0xae: movl $0,%gs:0x680 TID PID UID PRFLAGS PFLAGS CPU COMMAND *174942 72515 0 0 0 1 syz-executor 456124 30927 0 0x2 0 0 syz-executor savectx() at savectx+0xae end of kernel end trace frame: 0x7376d92deaf0, 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(0xfffffd805f202b68, 0x0, 0, 1) -> e ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7376d92deaf0, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80003c489500 rbx 0 rdx 0 rcx 0xffff80003c423c58 rax 0x3b r8 0xffff80003c489430 r9 0x1 r10 0xb3031a70cfc01460 r11 0xf3b442074619a420 r12 0 r13 0 r14 0xffff80003c423c58 r15 0 rip 0xffffffff81a0b3ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80003c489480 ss 0 savectx+0xae: movl $0,%gs:0x680 ddb{1}> show proc PROC (syz-executor) tid=174942 pid=72515 tcnt=3 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=0xffff80003c422f88,0xffff80003c422d08 process=0xffff8000fffed760 user=0xffff80003c484000, vmspace=0xfffffd806bfaed38 estcpu=36, cpticks=5, pctcpu=0.0, user=5, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *72515 174942 99773 0 7 0 syz-executor 72515 438448 99773 0 3 0x4000080 fsleep syz-executor 72515 227058 99773 0 2 0x4000000 syz-executor 4432 128876 23140 0 2 0 syz-executor 4432 236984 23140 0 3 0x4000080 fifor syz-executor 4432 132827 23140 0 2 0x4000000 syz-executor 30927 456124 1604 0 7 0x2 syz-executor 26218 80946 15460 0 3 0x80 nanoslp syz-executor 26218 507636 15460 0 3 0x4000080 kqsel syz-executor 26218 146756 15460 0 3 0x4000080 fsleep syz-executor 26218 245333 15460 0 3 0x4000080 fsleep syz-executor 2145 364222 1604 0 3 0x2 biowait syz-executor 57654 361159 0 0 3 0x14200 acct acct 23140 15458 1604 0 3 0x82 nanoslp syz-executor 46529 420387 1 0 3 0x100083 ttyin getty 99773 454408 1604 0 3 0x82 nanoslp syz-executor 23718 492406 1604 0 3 0x2 biowait syz-executor 15460 81487 1604 0 3 0x82 nanoslp syz-executor 39830 481373 1604 0 3 0x82 wait syz-executor 67416 328946 1604 0 3 0x82 nanoslp syz-executor 11384 487515 0 0 3 0x14200 bored sosplice 1604 169464 3751 0 3 0x82 kqread syz-executor 3751 414432 18646 0 3 0x10008a sigsusp ksh 18646 422031 47618 0 3 0x98 kqread sshd-session 47618 151215 89107 0 3 0x92 kqread sshd-session 89107 304027 1 0 3 0x88 kqread sshd 77023 437857 77735 74 3 0x1100092 bpf pflogd 77735 97698 1 0 3 0x80 sbwait pflogd 68670 382188 94540 73 3 0x1100090 kqread syslogd 94540 85428 1 0 3 0x100082 sbwait syslogd 11143 419943 1 0 3 0x100080 kqread resolvd 6018 341143 0 0 3 0x14200 bored smr 12288 263175 0 0 2 0x14200 zerothread 25268 350992 0 0 3 0x14200 aiodoned aiodoned 49768 298621 0 0 3 0x14200 syncer update 39627 311322 0 0 3 0x14200 cleaner cleaner 9498 170234 0 0 3 0x14200 reaper reaper 78484 221354 0 0 3 0x14200 pgdaemon pagedaemon 88214 57727 0 0 3 0x14200 bored viomb 95084 129828 0 0 3 0x40014200 acpi0 acpi0 21992 129840 0 0 3 0x40014200 idle1 6309 321836 0 0 3 0x14200 bored softnet3 9291 137928 0 0 3 0x14200 bored softnet2 39072 65735 0 0 3 0x14200 bored softnet1 75143 22878 0 0 3 0x14200 netlock softnet0 66648 507842 0 0 2 0x40014200 systqmp 79348 89911 0 0 3 0x14200 bored systq 44139 275838 0 0 3 0x14200 tmoslp softclockmp 56721 63615 0 0 3 0x40014200 tmoslp softclock 29208 93248 0 0 3 0x40014200 idle0 1 54204 0 0 3 0x80082 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 72515 (syz-executor) thread 0xffff8000ffff2010 (227058) Process 30927 (syz-executor) thread 0xffff8000ffff27c0 (456124) Process 2145 (syz-executor) thread 0xffff80002a2b4ce8 (364222) Process 23718 (syz-executor) thread 0xffff8000ffff1210 (492406) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10244 11092K 12527K 166960K 18392 0 pcb 17 17K 19K 166960K 1430 0 rtable 147 10K 12K 166960K 1326 0 pf 39 18K 82K 166960K 527 0 ifaddr 28 5K 8K 166960K 322 0 ifgroup 63 2K 3K 166960K 634 0 sysctl 4 1K 5K 166960K 7 0 counters 68 36K 38K 166960K 698 0 ioctlops 0 0K 4K 166960K 2453 0 iov 0 0K 18K 166960K 424 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1520 96K 96K 166960K 6031 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 100 0 VM map 2 1K 1K 166960K 2 0 sem 25 17K 33K 166960K 62 0 dirhash 12 2K 3K 166960K 114 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 16 57K 110K 166960K 5079 0 sigio 1 0K 0K 166960K 180 0 proc 67 79K 128K 166960K 1493 0 subproc 72 4K 4K 166960K 227 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 1208 0 in_multi 35 2K 7K 166960K 420 0 ether_multi 1 0K 0K 166960K 39 0 mrt 1 0K 0K 166960K 18 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 283 1261K 1261K 166960K 283 0 exec 0 0K 1K 166960K 1362 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 9 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 213 135K 174K 166960K 47377 0 UVM aobj 131 5K 5K 166960K 136 0 pinsyscall 35 70K 100K 166960K 6697 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 1K 166960K 327 0 NDP 16 0K 2K 166960K 231 0 temp 82 8692K 8948K 166960K 222525 0 kqueue 8 14K 32K 166960K 872 0 SYN cache 2 10K 18K 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 120 588 0 587 5 3 2 3 0 8 1 rtentry 176 387 0 335 6 2 4 6 0 8 0 unpcb 144 4647 0 4635 24 19 5 6 0 8 4 syncache 336 30 0 30 11 10 1 1 0 8 1 tcpqe 32 6 0 6 5 5 0 1 0 8 0 tcpcb 808 1729 0 1722 33 31 2 8 0 8 1 arp 128 59 0 45 1 0 1 1 0 8 0 inpcb 384 6210 0 6202 58 50 8 16 0 8 6 nd6 144 85 0 75 2 1 1 2 0 8 0 pkpcb 40 52 0 52 6 6 0 1 0 8 0 kcovpl 48 25 0 17 1 0 1 1 0 8 0 mppekey 1024 6 0 6 5 5 0 1 0 8 0 ppxss 1192 226 0 226 6 5 1 1 0 8 1 pppxif 1504 49 0 49 7 6 1 1 0 8 1 pfstscr 40 3 0 3 2 2 0 1 0 8 0 pffrag 232 24 0 17 2 1 1 1 0 482 0 pffrnode 88 24 0 17 2 1 1 1 0 8 0 pffrent 40 39 0 32 2 1 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 pftag 88 1 0 0 1 0 1 1 0 8 0 pfstitem 24 253 0 181 1 0 1 1 0 8 0 pfstkey 128 255 0 183 4 0 4 4 0 8 1 pfstate 384 253 0 181 10 1 9 10 0 8 1 pfrule 1344 23 0 17 2 1 1 2 0 8 0 rttmr 136 2 0 2 1 1 0 1 0 8 0 art_heap8 4096 4 0 0 4 0 4 4 0 8 0 art_heap4 256 1590 0 1407 34 20 14 30 0 8 0 art_table 32 1594 0 1407 4 1 3 4 0 8 0 art_node 16 362 0 322 1 0 1 1 0 8 0 sysvmsgpl 40 30 0 13 1 0 1 1 0 8 0 semupl 112 3 0 3 3 3 0 1 0 8 0 semapl 112 56 0 33 1 0 1 1 0 8 0 shmpl 112 133 0 5 4 0 4 4 0 8 0 dirhash 1024 85 0 68 3 0 3 3 0 8 0 dino2pl 256 10761 0 9223 97 0 97 97 0 8 0 ffsino 288 10761 0 9223 112 1 111 111 0 8 0 nchpl 144 17849 0 17265 64 39 25 64 0 8 0 rtmask 32 24 0 24 5 5 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 65031 0 65030 4 3 1 2 0 8 0 percpumem 16 364 0 315 1 0 1 1 0 8 0 kstatmem 264 364 0 336 4 1 3 3 0 8 0 scsiplug 72 19 0 19 11 10 1 1 0 8 1 scxspl 216 54817 0 54815 17 15 2 8 1 8 1 plimitpl 152 1190 0 1174 1 0 1 1 0 8 0 sigapl 424 5368 0 5321 10 3 7 9 0 8 0 futexpl 64 78628 0 78625 1 0 1 1 0 8 0 knotepl 120 735 0 0 21 0 21 21 0 8 0 kqueuepl 224 1995 0 1988 17 15 2 5 0 8 1 pipepl 336 881 0 854 16 10 6 8 0 8 3 fdescpl 520 5317 0 5290 3 0 3 3 0 8 0 filepl 160 39579 0 39383 44 28 16 18 0 8 3 lockfpl 104 1883 0 1872 6 4 2 3 0 8 0 lockfspl 48 805 0 796 1 0 1 1 0 8 0 sessionpl 144 71 0 63 1 0 1 1 0 8 0 pgrppl 48 302 0 286 1 0 1 1 0 8 0 ucredpl 104 7114 0 7104 1 0 1 1 0 8 0 zombiepl 144 6401 0 6399 1 0 1 1 0 8 0 processpl 1192 5368 0 5321 6 1 5 6 0 8 0 procpl 656 13214 0 13160 8 2 6 8 0 8 0 srpgc 96 40 0 40 7 7 0 1 0 8 0 sosppl 168 31 0 31 6 5 1 1 0 8 1 sockpl 728 11579 0 11558 83 69 14 21 0 8 11 mcl64k 65536 8 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 119 0 0 14 0 14 14 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 72 0 0 7 1 6 7 0 8 0 mtagpl 96 122 0 0 3 0 3 3 0 8 0 mbufpl 256 1273 0 0 78 0 78 78 0 8 0 bufpl 280 15223 0 9080 440 0 440 440 0 8 0 anonpl 32 16416 0 0 132 0 132 132 0 246 0 amapchunkpl 152 159763 0 159235 68 36 32 34 0 158 7 amappl16 200 14374 0 13980 117 84 33 36 0 8 1 amappl15 192 3 0 3 1 1 0 1 0 8 0 amappl14 184 205 0 196 1 0 1 1 0 8 0 amappl13 176 13 0 13 4 4 0 1 0 8 0 amappl12 168 6245 0 6219 3 1 2 2 0 8 0 amappl11 160 80 0 72 1 0 1 1 0 8 0 amappl10 152 6 0 5 1 0 1 1 0 8 0 amappl9 144 251 0 251 1 1 0 1 0 8 0 amappl8 136 25 0 22 1 0 1 1 0 8 0 amappl7 128 171 0 161 1 0 1 1 0 8 0 amappl6 120 372 0 368 1 0 1 1 0 8 0 amappl5 112 209 0 202 1 0 1 1 0 8 0 amappl4 104 483 0 463 1 0 1 1 0 8 0 amappl3 96 33640 0 33543 7 3 4 4 0 8 0 amappl2 88 1092 0 1045 2 0 2 2 0 8 0 amappl1 80 35211 0 34698 16 1 15 15 0 8 0 amappl 88 45230 0 45073 7 2 5 5 0 92 0 dma8192 8192 1 0 1 1 1 0 1 0 8 0 dma4096 4096 3 0 3 3 3 0 1 0 8 0 dma2048 2048 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 13 0 13 7 6 1 1 0 8 1 dma128 128 260 0 260 6 5 1 1 0 8 1 dma64 64 7 0 7 2 2 0 1 0 8 0 dma32 32 8 0 8 2 2 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 135 0 5 3 0 3 3 0 8 0 uaddrrnd 24 5317 0 5290 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5317 0 5290 1 0 1 1 0 8 0 vmmpekpl 168 39846 0 39779 4 0 4 4 0 8 0 vmmpepl 168 337991 0 335995 165 49 116 118 0 357 10 vmsppl 480 5316 0 5290 6 1 5 5 0 8 0 rwobjpl 72 88186 0 80957 142 5 137 139 0 8 0 pdppl 4096 10642 0 10580 144 76 68 84 0 8 6 pvpl 32 23055 0 0 185 0 185 185 0 265 0 pmappl 256 5316 0 5290 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 581 0 168 13 0 13 13 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff837edff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x33 kd_curproc sys/dev/kcov.c:585 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x33 sys/dev/kcov.c:153 __mp_lock(ffffffff838f4440) at __mp_lock+0x1a3 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff838f4440) at __mp_lock+0x1a3 sys/kern/kern_lock.c:144 softintr_dispatch(2) at softintr_dispatch+0x5b sys/arch/amd64/amd64/softintr.c:88 Xsofttty() at Xsofttty+0x27 __mp_lock(ffffffff838f4440) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff838f4440) at __mp_lock+0x192 sys/kern/kern_lock.c:144 intr_handler(ffff80003c45afb0,ffff800000079f00) at intr_handler+0xe1 sys/arch/amd64/amd64/intr.c:553 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc __mp_acquire_count(ffffffff838f4440,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 mi_switch() at mi_switch+0x4b7 sys/kern/sched_bsd.c:441 yield() at yield+0x6a sys/kern/sched_bsd.c:320 end trace frame: 0xffff80003c45b230, count: 0 ddb{0}> trace x86_ipi_db(ffffffff837edff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x33 kd_curproc sys/dev/kcov.c:585 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x33 sys/dev/kcov.c:153 __mp_lock(ffffffff838f4440) at __mp_lock+0x1a3 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff838f4440) at __mp_lock+0x1a3 sys/kern/kern_lock.c:144 softintr_dispatch(2) at softintr_dispatch+0x5b sys/arch/amd64/amd64/softintr.c:88 Xsofttty() at Xsofttty+0x27 __mp_lock(ffffffff838f4440) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff838f4440) at __mp_lock+0x192 sys/kern/kern_lock.c:144 intr_handler(ffff80003c45afb0,ffff800000079f00) at intr_handler+0xe1 sys/arch/amd64/amd64/intr.c:553 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc __mp_acquire_count(ffffffff838f4440,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 mi_switch() at mi_switch+0x4b7 sys/kern/sched_bsd.c:441 yield() at yield+0x6a sys/kern/sched_bsd.c:320 pool_get(ffffffff839506e0,1) at pool_get+0x265 sys/kern/subr_pool.c:593 uvm_mapent_alloc(fffffd806bfae018,0) at uvm_mapent_alloc+0x35a sys/uvm/uvm_map.c:-1 uvm_map_mkentry(fffffd806bfae018,fffffd806c89aa30,fffffd806c89aa30,e5c86a5e000,23000,0,839f3660933864ef,23000) at uvm_map_mkentry+0x87 sys/uvm/uvm_map.c:-1 uvm_mapent_clone(fffffd806bfae018,e5c86a5e000,23000,0,3,7,3f7ad84f9a5c1789,fffffd806aee7eb8,ffff80003c45b488,fffffd806bfae018) at uvm_mapent_clone+0xba sys/uvm/uvm_map.c:3549 uvm_mapent_forkcopy(1,fffffd806bfae018,fffffd806bfae978,fffffd806aee7eb8,ffff80003c45b488) at uvm_mapent_forkcopy+0x6e sys/uvm/uvm_map.c:3641 uvmspace_fork(ffff8000fffedc08) at uvmspace_fork+0x2bb sys/uvm/uvm_map.c:3844 process_new(ffff80002a2b4f78,ffff8000fffedc08,a) at process_new+0x572 sys/kern/kern_fork.c:283 fork1(ffff8000ffff27c0,a,ffffffff826d7940,0,ffff80003c45b660,0) at fork1+0x3ea sys/kern/kern_fork.c:409 syscall(ffff80003c45b710) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c45b710) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ac22ce21b30, count: -24 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x680 savectx() at savectx+0xae end of kernel end trace frame: 0x7376d92deaf0, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7376d92deaf0, count: -1