login: uvm_fault(0xfffff3806cce9b90, 0x98, 0, 1) -> e
fatal page fault in supervisor mode
trap type 6 code 0 rip ffffffff81b69318 cs 8 rflags 10246 cr2 98 cpl 0 rsp ffff80003c3d2a00
gsbase 0xffff80002999dff0 kgsbase 0x0
panic: trap type 6, code=0, pc=ffffffff81b69318
Starting stack trace...
panic(ffffffff834ef33e) at panic+0x1d0 sys/kern/subr_prf.c:229
kerntrap(ffff80003c3d2950) at kerntrap+0x30b
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
dovutimens(ffff800045ff2a78,fffff3806cecba78,ffff80003c3d2b30) at dovutimens+0x368 sys/kern/vfs_syscalls.c:2691
sys_futimes(ffff800045ff2a78,ffff80003c3d2c80,ffff80003c3d2bd0) at sys_futimes+0x208 sys/kern/vfs_syscalls.c:2733
syscall(ffff80003c3d2c80) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c3d2c80) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6ea25073f90, count: 250
End of stack trace.
WARNING: SPL NOT LOWERED ON SYSCALL 83 1181525520 EXIT 0 4
Stopped at savectx+0xae: movl $0,%gs:0x688
TID PID UID PRFLAGS PFLAGS CPU COMMAND
507299 46403 0 0 0 0K syz-executor
*285740 46403 0 0 0x4000000 1 syz-executor
savectx() at savectx+0xae
end of kernel
end trace frame: 0x6ea791d1770, 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(0xfffff3806cce9b90, 0x98, 0, 1) -> e
ddb{1}> show kasan
No such command
ddb{1}> trace
savectx() at savectx+0xae
end of kernel
end trace frame: 0x6ea791d1770, count: -1
ddb{1}> show registers
rdi 0
rsi 0
rbp 0xffff800033f98c00
rbx 0
rdx 0
rcx 0xffff800045ff3ca0
rax 0x3b
r8 0xffff800033f98b30
r9 0x1
r10 0xc8c0ffc54cf49c58
r11 0x682798bd167894bc
r12 0
r13 0
r14 0xffff800045ff3ca0
r15 0
rip 0xffffffff81c2f3ee savectx+0xae
cs 0x8
rflags 0x46
rsp 0xffff800033f98b80
ss 0x10
savectx+0xae: movl $0,%gs:0x688
ddb{1}> show proc
PROC (syz-executor) tid=285740 pid=46403 tcnt=4 stat=onproc
flags process=0 proc=4000000<THREAD>
runpri=32, usrpri=66, slppri=32, nice=20
wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
forw=0xffffffffffffffff, list=0xffff800045ff3240,0xffffffff83ad69a0
process=0xffff800045fee698 user=0xffff800033f93000, vmspace=0xfffff3806cce9b90
estcpu=16, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb{1}> ps
PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND
71539 131105 79742 0 2 0x2 0 sh
13541 343294 38564 0 2 0 0 syz-executor
13541 297913 38564 0 3 0 0x4000080 fsleep syz-executor
46403 507299 37086 0 7 0 0 syz-executor
46403 481962 37086 0 3 0 0x4000080 kqsel syz-executor
46403 92445 37086 0 3 0 0x4000000 sbar syz-executor
*46403 285740 37086 0 7 0 0x4000000 syz-executor
23778 366596 27520 0 2 0 0 syz-executor
32644 129541 2003 0 2 0 0 syz-executor
32644 405464 2003 0 3 0 0x4000080 fsleep syz-executor
79742 396252 53254 0 3 0x2 0x80 wait syz-executor
27520 355436 53254 0 2 0x2 0xc80 syz-executor
5944 446644 1 0 2 0x100003 0x80 getty
33077 413734 53254 0 2 0x2 0 syz-executor
31366 447049 53254 0 2 0x2 0 syz-executor
38564 355779 53254 0 2 0x2 0xc80 syz-executor
37086 59407 53254 0 2 0x2 0xc80 syz-executor
2003 260606 53254 0 2 0x2 0xc80 syz-executor
88474 153290 53254 0 3 0x2 0x80 wait syz-executor
53254 220235 83503 0 2 0x2 0 syz-executor
83503 488761 88428 0 3 0x100002 0x88 sigsusp ksh
88428 103312 89228 0 3 0x10 0x88 kqread sshd-session
89228 179544 28906 0 3 0x12 0x80 kqread sshd-session
28906 507579 1 0 3 0 0x88 kqread sshd
90323 453315 10501 74 3 0x1100012 0x80 bpf pflogd
10501 389444 1 0 3 0 0x80 sbwait pflogd
59592 230597 5440 73 3 0x1100010 0x80 kqread syslogd
5440 68665 1 0 3 0x100002 0x80 sbwait syslogd
44896 415557 1 0 3 0x100000 0x80 kqread resolvd
21059 249184 8780 77 3 0x100012 0x80 kqread dhcpleased
44159 309690 8780 77 3 0x100012 0x80 kqread dhcpleased
8780 226467 1 0 3 0 0x80 kqread dhcpleased
99865 323373 0 0 2 0x14000 0x200 smr
86969 232427 0 0 2 0x14000 0x200 zerothread
2015 260538 0 0 3 0x14000 0x200 aiodoned aiodoned
45994 59974 0 0 3 0x14000 0x200 syncer update
74918 49038 0 0 3 0x14000 0x200 cleaner cleaner
27613 154879 0 0 3 0x14000 0x200 reaper reaper
9060 308526 0 0 3 0x14000 0x200 pgdaemon pagedaemon
84324 11659 0 0 3 0x14000 0x200 bored viomb
84435 99233 0 0 3 0x14000 0x40000200 acpi0 acpi0
29639 454584 0 0 3 0x14000 0x40000200 idle1
97742 431809 0 0 3 0x14000 0x200 bored softnet1
23944 75606 0 0 2 0x14000 0x200 softnet0
86724 38256 0 0 2 0x14000 0x200 systqmp
77619 367937 0 0 3 0x14000 0x200 bored systq
80411 73496 0 0 2 0x14000 0x200 softclockmp
13870 137688 0 0 3 0x14000 0x40000200 tmoslp softclock
79142 204671 0 0 3 0x14000 0x40000200 idle0
1 94959 0 0 3 0x2 0x80 wait init
0 0 -1 0 3 0x10010000 0x200 scheduler swapper
ddb{1}> show all locks
Process 46403 (syz-executor) thread 0xffff800045ff2a78 (92445)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff839e9300)
#0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1 syscall+0xaf4 mi_syscall sys/sys/syscall_mi.h:175 [inline]
#1 syscall+0xaf4 sys/arch/amd64/amd64/trap.c:783
#2 Xsyscall+0x128
Process 33077 (syz-executor) thread 0xffff800045fea7e8 (413734)
exclusive rrwlock inode r = 0 (0xfffff3806edd10e8)
#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+0xbd sys/kern/vfs_vops.c:527
#4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline]
#4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:150
#5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1232
#6 ffs_inode_alloc+0x279 sys/ufs/ffs/ffs_alloc.c:393
#7 ufs_mkdir+0xfc sys/ufs/ufs/ufs_vnops.c:1112
#8 VOP_MKDIR+0x101 sys/kern/vfs_vops.c:394
#9 domkdirat+0x179 sys/kern/vfs_syscalls.c:3063
#10 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#10 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#11 Xsyscall+0x128
exclusive rrwlock inode r = 0 (0xfffff3806d0df560)
#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+0xbd sys/kern/vfs_vops.c:527
#4 vn_lock+0xa4 sys/kern/vfs_vnops.c:576
#5 vfs_lookup+0x12b sys/kern/vfs_lookup.c:431
#6 namei+0x7c5 sys/kern/vfs_lookup.c:250
#7 domkdirat+0x8b sys/kern/vfs_syscalls.c:3048
#8 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#8 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#9 Xsyscall+0x128
Process 31366 (syz-executor) thread 0xffff800045feafb0 (447049)
exclusive rrwlock inode r = 0 (0xfffff3806caea460)
#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+0xbd sys/kern/vfs_vops.c:527
#4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline]
#4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:150
#5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1232
#6 ffs_inode_alloc+0x279 sys/ufs/ffs/ffs_alloc.c:393
#7 ufs_mkdir+0xfc sys/ufs/ufs/ufs_vnops.c:1112
#8 VOP_MKDIR+0x101 sys/kern/vfs_vops.c:394
#9 domkdirat+0x179 sys/kern/vfs_syscalls.c:3063
#10 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#10 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#11 Xsyscall+0x128
exclusive rrwlock inode r = 0 (0xfffff3806cad9440)
#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+0xbd sys/kern/vfs_vops.c:527
#4 vn_lock+0xa4 sys/kern/vfs_vnops.c:576
#5 vfs_lookup+0x12b sys/kern/vfs_lookup.c:431
#6 namei+0x7c5 sys/kern/vfs_lookup.c:250
#7 domkdirat+0x8b sys/kern/vfs_syscalls.c:3048
#8 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#8 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#9 Xsyscall+0x128
ddb{1}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 11064 12153K 12365K 166960K 13214 0
pcb 18 13K 14K 166960K 153 0
rtable 195 8K 10K 166960K 1572 0
pf 40 19K 37K 166960K 306 0
ifaddr 38 7K 9K 166960K 233 0
ifgroup 56 2K 2K 166960K 281 0
sysctl 4 1K 9K 166960K 17 0
counters 70 37K 37K 166960K 278 0
ioctlops 0 0K 4K 166960K 1727 0
iov 0 0K 16K 166960K 18 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1381 87K 87K 166960K 2437 0
UFS quota 1 32K 32K 166960K 1 0
UFS mount 5 36K 36K 166960K 5 0
shm 2 20K 24K 166960K 17 0
VM map 2 1K 1K 166960K 2 0
sem 12 0K 1K 166960K 106 0
dirhash 12 2K 2K 166960K 21 0
ACPI 1734 201K 291K 166960K 11964 0
file desc 16 57K 89K 166960K 1342 0
sigio 0 0K 0K 166960K 12 0
proc 72 115K 164K 166960K 1720 0
subproc 72 4K 4K 166960K 423 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 16K 16K 166960K 1 0
ip_moptions 0 0K 0K 166960K 70 0
in_multi 77 5K 6K 166960K 538 0
ether_multi 1 0K 0K 166960K 3 0
mrt 2 0K 0K 166960K 27 0
ISOFS mount 1 32K 32K 166960K 1 0
MSDOSFS mount 1 16K 16K 166960K 1 0
ttys 73 334K 334K 166960K 73 0
exec 0 0K 1K 166960K 1009 0
fusefs mount 1 32K 32K 166960K 1 0
tdb 3 0K 0K 166960K 3 0
VM swap 8 62K 64K 166960K 10 0
UVM amap 214 166K 195K 166960K 11612 0
UVM aobj 3 2K 2K 166960K 3 0
pinsyscall 41 82K 101K 166960K 3504 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 0 0K 0K 166960K 17 0
NDP 12 0K 2K 166960K 167 0
temp 77 9128K 9191K 166960K 39170 0
kqueue 13 20K 32K 166960K 135 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 28 0 0 1 0 1 1 0 8 0
rtpcb 120 166 0 163 2 1 1 2 0 8 0
rtentry 176 542 0 463 5 0 5 5 0 8 0
unpcb 144 637 0 620 6 5 1 6 0 8 0
syncache 336 6 0 6 3 3 0 1 0 8 0
tcpcb 736 202 0 198 4 3 1 4 0 8 0
arp 136 95 0 80 1 0 1 1 0 8 0
inpcb 328 845 0 836 6 4 2 5 0 8 1
nd6 152 141 0 123 1 0 1 1 0 8 0
pkpcb 40 3 0 3 3 2 1 1 0 8 1
kcovpl 48 47 0 39 1 0 1 1 0 8 0
ppxss 1192 57 0 57 3 2 1 1 0 8 1
pppxif 1576 35 0 35 2 2 0 1 0 8 0
pfstscr 40 7 0 4 2 1 1 1 0 8 0
pffrag 232 1 0 0 1 0 1 1 0 482 0
pffrnode 88 1 0 0 1 0 1 1 0 8 0
pffrent 40 2 0 1 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
pfsrclim 320 4 0 4 1 1 0 1 0 8 0
pfstlim 224 2 0 2 2 2 0 1 0 8 0
pfanchor 1288 16 0 10 2 1 1 2 0 8 0
pfstitem 24 75 0 33 1 0 1 1 0 8 0
pfstkey 128 80 0 38 2 0 2 2 0 8 0
pfstate 448 74 0 36 7 0 7 7 0 8 0
pfrule 1360 28 0 23 2 1 1 2 0 8 0
art_heap8 4096 2 0 0 2 0 2 2 0 8 0
art_heap4 256 2356 0 1987 34 4 30 34 0 8 3
art_table 40 2358 0 1987 6 0 6 6 0 8 0
art_node 32 542 0 473 1 0 1 1 0 8 0
sysvmsgpl 40 4 0 3 2 1 1 1 0 8 0
semupl 112 3 0 3 2 2 0 1 0 8 0
semapl 72 100 0 90 1 0 1 1 0 8 0
dirhash 1024 23 0 6 3 0 3 3 0 8 0
dino2pl 256 2749 0 1217 96 0 96 96 0 8 0
ffsino 296 2749 0 1217 118 0 118 118 0 8 0
nchpl 144 3823 0 1997 68 0 68 68 0 8 0
rtmask 32 5 0 5 1 1 0 1 0 8 0
vnodes 216 3719 0 0 207 0 207 207 0 8 0
namei 1024 15775 0 15773 2 1 1 1 0 8 0
percpumem 16 155 0 104 1 0 1 1 0 8 0
kstatmem 264 153 0 126 4 1 3 3 0 8 1
scsiplug 72 7 0 7 2 1 1 1 0 8 1
scxspl 216 12640 0 12640 11 10 1 8 1 8 1
plimitpl 152 126 0 109 1 0 1 1 0 8 0
sigapl 424 1603 0 1557 8 1 7 8 0 8 0
knotepl 120 681 0 0 21 0 21 21 0 8 0
kqueuepl 224 183 0 172 2 1 1 2 0 8 0
pipepl 344 286 0 258 3 0 3 3 0 8 0
fdescpl 528 1567 0 1537 3 0 3 3 0 8 0
filepl 160 7000 0 6782 16 6 10 15 0 8 0
lockfpl 104 417 0 415 2 1 1 2 0 8 0
lockfspl 48 191 0 189 1 0 1 1 0 8 0
sessionpl 144 127 0 118 1 0 1 1 0 8 0
pgrppl 48 180 0 163 1 0 1 1 0 8 0
ucredpl 104 732 0 719 1 0 1 1 0 8 0
zombiepl 144 1558 0 1557 2 1 1 1 0 8 0
processpl 1232 1603 0 1557 6 1 5 6 0 8 0
procpl 664 2655 0 2603 9 4 5 8 0 8 0
sockpl 752 1671 0 1641 20 15 5 17 0 8 2
mcl64k 65536 4 0 0 1 0 1 1 0 8 0
mcl16k 16384 4 0 0 1 0 1 1 0 8 0
mcl12k 12288 2 0 0 1 0 1 1 0 8 0
mcl9k128 9344 2 0 0 1 0 1 1 0 8 0
mcl8k 8192 7 0 0 1 0 1 1 0 8 0
mcl4k 4096 134 0 0 16 1 15 16 0 8 0
mcl2k 2048 19 0 0 3 0 3 3 0 8 0
mextrefs 64 20 0 0 1 0 1 1 0 8 0
mtagpl 96 9 0 0 1 0 1 1 0 8 0
mbufpl 256 220 0 0 14 0 14 14 0 8 0
bufpl 272 3700 0 107 240 0 240 240 0 8 0
anonpl 32 5733 0 0 47 0 47 47 0 247 0
amapchunkpl 152 35035 0 34625 37 18 19 36 0 158 0
amappl16 200 2342 0 2318 7 5 2 5 0 8 0
amappl15 192 2 0 2 1 1 0 1 0 8 0
amappl14 184 891 0 889 1 0 1 1 0 8 0
amappl13 176 217 0 205 1 0 1 1 0 8 0
amappl12 168 1972 0 1944 2 0 2 2 0 8 0
amappl11 160 18 0 18 1 1 0 1 0 8 0
amappl10 152 81 0 67 1 0 1 1 0 8 0
amappl9 144 287 0 286 1 0 1 1 0 8 0
amappl8 136 249 0 247 1 0 1 1 0 8 0
amappl7 128 227 0 212 1 0 1 1 0 8 0
amappl6 120 545 0 543 1 0 1 1 0 8 0
amappl5 112 110 0 99 1 0 1 1 0 8 0
amappl4 104 419 0 398 1 0 1 1 0 8 0
amappl3 96 7238 0 7136 4 0 4 4 0 8 0
amappl2 88 884 0 822 2 0 2 2 0 8 0
amappl1 80 17760 0 17159 16 2 14 15 0 8 0
amappl 88 10148 0 10007 5 0 5 5 0 92 0
uvmvnodes 80 116 0 0 3 0 3 3 0 8 0
dma65536 65536 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
dma256 256 7 0 7 2 2 0 1 0 8 0
dma128 128 255 0 255 2 2 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 2 0 0 1 0 1 1 0 8 0
uaddrrnd 24 1567 0 1537 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 1567 0 1537 1 0 1 1 0 8 0
vmmpekpl 168 13599 0 13556 3 0 3 3 0 8 0
vmmpepl 168 104830 0 103011 90 5 85 88 0 357 0
vmsppl 488 1566 0 1537 5 0 5 5 0 8 0
rwobjpl 80 29736 0 28697 24 1 23 23 0 8 0
pdppl 4096 3141 0 3074 153 80 73 83 0 8 6
pvpl 32 13556 0 0 110 0 110 110 0 265 0
pmappl 256 1566 0 1537 3 0 3 3 0 8 0
extentpl 40 46 0 28 1 0 1 1 0 8 0
phpool 112 590 0 97 15 0 15 15 0 8 0
ddb{1}> machine ddbcpu 0
Stopped at x86_ipi_db+0x27: addq $0x8,%rsp
x86_ipi_db(ffffffff83976ff0) 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
tfind(ffff800045feb4e0) at tfind
sys___tfork(ffff800045feb4e0,ffff800045fe77c0,ffff800045fe7710) at sys___tfork+0x1b6 sys/kern/kern_fork.c:141
syscall(ffff800045fe77c0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff800045fe77c0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x774d43a67740, count: 8
ddb{0}> trace
x86_ipi_db(ffffffff83976ff0) 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
tfind(ffff800045feb4e0) at tfind
sys___tfork(ffff800045feb4e0,ffff800045fe77c0,ffff800045fe7710) at sys___tfork+0x1b6 sys/kern/kern_fork.c:141
syscall(ffff800045fe77c0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff800045fe77c0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x774d43a67740, 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: 0x6ea791d1770, count: 14
ddb{1}> trace
savectx() at savectx+0xae
end of kernel
end trace frame: 0x6ea791d1770, count: -1