������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 959
Stopped at db_enter+0x25: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
416008 58155 0 0 0 0 syz-executor
*422976 58155 0 0 0x4000000 1K syz-executor
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff834c3a70) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff83504321,ffffffff835127f6,3bf,ffffffff8353b5ad) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80003c3d8c58,ffffffff834c027d) at refcnt_finalize+0x1e7 sys/kern/kern_synch.c:960
pppx_if_destroy(285b9c,ffff80003c3d8c50) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(285b9c,1,2000,ffff80002a2dd788) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff80002a364b50) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffa80715bae98,1,fffffa80097fd3a8,ffff80002a2dd788) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:298 [inline]
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b sys/kern/vfs_vnops.c:621
fdrop(fffffa806cf25670,ffff80002a2dd788) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffa806cf25670,ffff80002a2dd788) at closef+0x192 sys/kern/kern_descrip.c:1265
sys_closefrom(ffff80002a2dd788,ffff80002a364e20,ffff80002a364d70) at sys_closefrom+0x13c sys/kern/kern_descrip.c:1471
syscall(ffff80002a364e20) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a364e20) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcf0ef9e170, count: 1
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}>
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
*cpu1: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 959
ddb{1}> show kasan
No such command
ddb{1}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff834c3a70) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff83504321,ffffffff835127f6,3bf,ffffffff8353b5ad) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80003c3d8c58,ffffffff834c027d) at refcnt_finalize+0x1e7 sys/kern/kern_synch.c:960
pppx_if_destroy(285b9c,ffff80003c3d8c50) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(285b9c,1,2000,ffff80002a2dd788) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff80002a364b50) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffa80715bae98,1,fffffa80097fd3a8,ffff80002a2dd788) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:298 [inline]
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b sys/kern/vfs_vnops.c:621
fdrop(fffffa806cf25670,ffff80002a2dd788) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffa806cf25670,ffff80002a2dd788) at closef+0x192 sys/kern/kern_descrip.c:1265
sys_closefrom(ffff80002a2dd788,ffff80002a364e20,ffff80002a364d70) at sys_closefrom+0x13c sys/kern/kern_descrip.c:1471
syscall(ffff80002a364e20) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a364e20) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcf0ef9e170, count: -14
ddb{1}> show registers
rdi 0
rsi 0x1
rbp 0xffff80002a364910
rbx 0xffff80002999ee0f
rdx 0
rcx 0xffff80002a2dd788
rax 0xffff80002999dff0
r8 0x101010101010101
r9 0x8080808080808080
r10 0xf707fd20c1920b33
r11 0x98209fe9ff98c8f9
r12 0xffff80002999ec10
r13 0
r14 0
r15 0x1
rip 0xffffffff83087115 db_enter+0x25
cs 0x8
rflags 0x246
rsp 0xffff80002a364900
ss 0x10
db_enter+0x25: addq $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor) tid=422976 pid=58155 tcnt=3 stat=onproc
flags process=0 proc=4000000<THREAD>
runpri=32, usrpri=86, slppri=32, nice=20
wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
forw=0xffffffffffffffff, list=0xffff80002a2dc7f8,0xffffffff839f6a08
process=0xffff80002ac14500 user=0xffff80002a35f000, vmspace=0xfffffa806cf1f9a0
estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb{1}> ps
PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND
58172 180924 91956 0 3 0x2 0 clonelk ifconfig
91956 387953 96159 0 3 0x100002 0x88 sigsusp sh
58155 416008 44012 0 7 0 0 syz-executor
58155 398483 44012 0 3 0 0x4000000 smrbar syz-executor
*58155 422976 44012 0 7 0 0x4000000 syz-executor
96159 365225 68466 0 3 0x2 0x80 wait syz-executor
90640 292023 10952 0 3 0 0x80 nanoslp syz-executor
90640 263490 10952 0 3 0 0x4000080 ttyout syz-executor
44012 163831 68466 0 3 0x2 0x80 nanoslp syz-executor
69603 181184 0 0 3 0x14000 0x280 nfsidl nfsio
59871 221712 0 0 3 0x14000 0x280 nfsidl nfsio
78822 358668 0 0 3 0x14000 0x280 nfsidl nfsio
72607 400894 0 0 3 0x14000 0x280 nfsidl nfsio
50406 93002 0 0 3 0x14000 0x280 nfsidl nfsio
37031 478504 0 0 3 0x14000 0x280 nfsidl nfsio
72323 382167 0 0 3 0x14000 0x280 nfsidl nfsio
96820 346368 0 0 3 0x14000 0x280 nfsidl nfsio
60745 314763 0 0 3 0x14000 0x280 nfsidl nfsio
61797 238623 0 0 3 0x14000 0x280 nfsidl nfsio
79505 522310 0 0 3 0x14000 0x280 nfsidl nfsio
33828 484237 0 0 3 0x14000 0x280 nfsidl nfsio
18340 380392 0 0 3 0x14000 0x280 nfsidl nfsio
80826 450927 0 0 3 0x14000 0x280 nfsidl nfsio
96253 424674 0 0 3 0x14000 0x280 nfsidl nfsio
81123 396317 0 0 3 0x14000 0x280 nfsidl nfsio
76547 512702 0 0 3 0x14000 0x280 nfsidl nfsio
4150 439413 0 0 3 0x14000 0x280 nfsidl nfsio
4503 325462 0 0 3 0x14000 0x280 nfsidl nfsio
31059 228115 0 0 3 0x14000 0x280 nfsidl nfsio
47561 110152 68466 0 3 0x2 0x80 piperd syz-executor
60023 217613 68466 0 3 0x2 0x80 piperd syz-executor
19984 395612 68466 0 3 0x2 0x80 piperd syz-executor
10952 107990 68466 0 3 0x2 0x80 nanoslp syz-executor
68466 83238 13403 0 3 0x2 0x80 wait syz-executor
13403 286525 81253 0 3 0x100002 0x88 sigsusp ksh
81253 447931 14798 0 3 0x10 0x88 kqread sshd-session
14798 517381 35179 0 3 0x12 0x80 kqread sshd-session
89273 94508 1 0 3 0x100003 0x80 ttyin getty
35179 253463 1 0 3 0 0x88 kqread sshd
11330 245025 59092 74 3 0x1100012 0x80 bpf pflogd
59092 511092 1 0 3 0 0x80 sbwait pflogd
34283 385066 48535 73 3 0x1100010 0x80 kqread syslogd
48535 513851 1 0 3 0x100002 0x80 sbwait syslogd
43284 43319 1 0 3 0x100000 0x80 kqread resolvd
17389 407751 90064 77 3 0x100012 0x80 kqread dhcpleased
68344 43930 90064 77 3 0x100012 0x80 kqread dhcpleased
90064 397623 1 0 3 0 0x80 kqread dhcpleased
70101 34908 0 0 3 0x14000 0x200 bored smr
24157 309058 0 0 3 0x14000 0x200 pgzero zerothread
44737 144155 0 0 3 0x14000 0x200 aiodoned aiodoned
36799 337002 0 0 3 0x14000 0x200 syncer update
45809 445494 0 0 3 0x14000 0x200 cleaner cleaner
66698 17548 0 0 3 0x14000 0x200 reaper reaper
96601 91376 0 0 3 0x14000 0x200 pgdaemon pagedaemon
4938 216245 0 0 3 0x14000 0x200 bored viomb
68923 309733 0 0 3 0x14000 0x40000200 acpi0 acpi0
83006 281479 0 0 3 0x14000 0x40000200 idle1
51055 175027 0 0 3 0x14000 0x200 bored softnet1
55426 398269 0 0 3 0x14000 0x200 bored softnet0
59131 248271 0 0 3 0x14000 0x200 smrbar systqmp
75853 32579 0 0 3 0x14000 0x200 bored systq
97640 471007 0 0 3 0x14000 0x200 tmoslp softclockmp
984 523449 0 0 3 0x14000 0x40000200 tmoslp softclock
17830 225085 0 0 3 0x14000 0x40000200 idle0
1 462704 0 0 3 0x2 0x80 wait init
0 0 -1 0 3 0x10000 0x200 scheduler swapper
ddb{1}> show all locks
Process 58155 (syz-executor) thread 0xffff80002a2dd788 (422976)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff83a85780)
#0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1 vn_closefile+0x41 sys/kern/vfs_vnops.c:614
#2 fdrop+0x121 sys/kern/kern_descrip.c:1281
#3 closef+0x192 sys/kern/kern_descrip.c:1265
#4 sys_closefrom+0x13c sys/kern/kern_descrip.c:1471
#5 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#5 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:791
#6 Xsyscall+0x128
Process 59131 (systqmp) thread 0xffff800045ffe7c8 (248271)
shared rwlock systqmp r = 0 (0xffffffff839c3f58)
#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 11055 12083K 12093K 166960K 12185 0
pcb 18 14K 16K 166960K 112 0
rtable 219 6K 7K 166960K 485 0
pf 38 18K 20K 166960K 70 0
ifaddr 42 7K 8K 166960K 75 0
ifgroup 60 2K 2K 166960K 98 0
sysctl 1 1K 9K 166960K 5 0
counters 76 37K 37K 166960K 102 0
ioctlops 0 0K 4K 166960K 1497 0
iov 1 0K 2K 166960K 3 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1294 81K 81K 166960K 1429 0
UFS quota 1 32K 32K 166960K 1 0
UFS mount 5 36K 36K 166960K 5 0
shm 2 1K 5K 166960K 3 0
VM map 2 1K 1K 166960K 2 0
sem 4 0K 0K 166960K 4 0
dirhash 12 2K 2K 166960K 12 0
ACPI 1692 195K 286K 166960K 12470 0
file desc 14 49K 93K 166960K 246 0
sigio 0 0K 0K 166960K 2 0
proc 79 131K 164K 166960K 677 0
subproc 72 4K 4K 166960K 117 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 16K 16K 166960K 1 0
ip_moptions 0 0K 0K 166960K 1 0
in_multi 89 6K 6K 166960K 149 0
ether_multi 1 0K 0K 166960K 1 0
mrt 0 0K 0K 166960K 3 0
ISOFS mount 1 32K 32K 166960K 1 0
MSDOSFS mount 1 16K 16K 166960K 1 0
ttys 37 175K 175K 166960K 37 0
exec 0 0K 1K 166960K 441 0
fusefs mount 1 32K 32K 166960K 1 0
pfkey data 0 0K 0K 166960K 1 0
tdb 3 0K 0K 166960K 3 0
VM swap 8 62K 64K 166960K 10 0
UVM amap 194 159K 169K 166960K 3793 0
UVM aobj 7 2K 2K 166960K 7 0
pinsyscall 39 78K 104K 166960K 1510 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 1 0K 0K 166960K 4 0
NDP 19 0K 1K 166960K 46 0
temp 35 9118K 9138K 166960K 4100 0
kqueue 14 22K 26K 166960K 32 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 47 0 44 1 0 1 1 0 8 0
rtentry 176 161 0 61 6 0 6 6 0 8 0
unpcb 144 61 0 44 1 0 1 1 0 8 0
syncache 336 5 0 5 1 0 1 1 0 8 1
tcpcb 736 18 0 14 1 0 1 1 0 8 0
arp 136 26 0 10 1 0 1 1 0 8 0
inpcb 328 189 0 180 6 0 6 6 0 8 5
nd6 152 36 0 15 1 0 1 1 0 8 0
pkpcb 40 1 0 1 1 0 1 1 0 8 1
kcovpl 48 13 0 5 1 0 1 1 0 8 0
ppxss 1192 6 0 4 1 0 1 1 0 8 0
pppxif 1576 6 0 4 1 0 1 1 0 8 0
pffrag 232 3 0 1 1 0 1 1 0 482 0
pffrnode 88 3 0 1 1 0 1 1 0 8 0
pffrent 40 5 0 3 1 0 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
pfstitem 24 34 0 0 1 0 1 1 0 8 0
pfstkey 128 34 0 0 2 0 2 2 0 8 0
pfstate 448 33 0 0 4 0 4 4 0 8 0
pfrule 1360 21 0 16 2 1 1 2 0 8 0
art_heap8 4096 1 0 0 1 0 1 1 0 8 0
art_heap4 256 649 0 232 29 0 29 29 0 8 1
art_table 40 650 0 232 5 0 5 5 0 8 0
art_node 32 161 0 58 1 0 1 1 0 8 0
sysvmsgpl 40 4 0 3 1 0 1 1 0 8 0
semapl 72 2 0 0 1 0 1 1 0 8 0
shmpl 120 4 0 0 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1645 0 163 93 0 93 93 0 8 0
ffsino 296 1645 0 163 115 0 115 115 0 8 0
nchpl 144 1907 0 184 64 0 64 64 0 8 0
vnodes 216 1790 0 0 100 0 100 100 0 8 0
namei 1024 7161 0 7161 4 1 3 3 0 8 3
percpumem 16 67 0 13 1 0 1 1 0 8 0
kstatmem 264 47 0 18 3 0 3 3 0 8 1
scxspl 216 6502 0 6502 4 3 1 3 1 8 1
plimitpl 152 102 0 85 1 0 1 1 0 8 0
sigapl 424 573 0 509 8 0 8 8 0 8 0
knotepl 120 185 0 0 6 0 6 6 0 8 0
kqueuepl 224 35 0 25 1 0 1 1 0 8 0
pipepl 344 145 0 118 3 0 3 3 0 8 0
fdescpl 528 537 0 509 3 0 3 3 0 8 0
filepl 160 2026 0 1815 12 0 12 12 0 8 2
lockfpl 104 31 0 29 1 0 1 1 0 8 0
lockfspl 48 16 0 14 1 0 1 1 0 8 0
sessionpl 144 29 0 20 1 0 1 1 0 8 0
pgrppl 48 43 0 26 1 0 1 1 0 8 0
ucredpl 104 107 0 94 1 0 1 1 0 8 0
zombiepl 144 511 0 509 1 0 1 1 0 8 0
processpl 1240 573 0 509 6 0 6 6 0 8 0
procpl 664 660 0 593 8 0 8 8 0 8 1
sockpl 752 300 0 271 10 0 10 10 0 8 7
mcl64k 65536 2 0 0 1 0 1 1 0 8 0
mcl12k 12288 2 0 0 1 0 1 1 0 8 0
mcl8k 8192 2 0 0 1 0 1 1 0 8 0
mcl4k 4096 115 0 0 15 0 15 15 0 8 0
mcl2k 2048 23 0 0 3 0 3 3 0 8 0
mextrefs 64 18 0 0 1 0 1 1 0 8 0
mtagpl 96 2 0 0 1 0 1 1 0 8 0
mbufpl 256 180 0 0 12 0 12 12 0 8 0
bufpl 272 2350 0 105 150 0 150 150 0 8 0
anonpl 32 3599 0 0 30 0 30 30 0 247 0
amapchunkpl 152 10156 0 9797 21 0 21 21 0 158 3
amappl16 200 1353 0 1338 4 2 2 4 0 8 0
amappl15 192 5 0 5 1 1 0 1 0 8 0
amappl14 184 544 0 542 1 0 1 1 0 8 0
amappl13 176 132 0 120 1 0 1 1 0 8 0
amappl12 168 803 0 777 2 0 2 2 0 8 0
amappl11 160 2 0 2 1 1 0 1 0 8 0
amappl10 152 64 0 50 1 0 1 1 0 8 0
amappl9 144 272 0 272 1 1 0 1 0 8 0
amappl8 136 115 0 112 1 0 1 1 0 8 0
amappl7 128 160 0 147 1 0 1 1 0 8 0
amappl6 120 197 0 194 1 0 1 1 0 8 0
amappl5 112 97 0 87 1 0 1 1 0 8 0
amappl4 104 312 0 293 1 0 1 1 0 8 0
amappl3 96 1859 0 1786 3 0 3 3 0 8 0
amappl2 88 639 0 567 2 0 2 2 0 8 0
amappl1 80 11064 0 10467 14 0 14 14 0 8 0
amappl 88 2997 0 2875 4 0 4 4 0 92 0
uvmvnodes 80 100 0 0 3 0 3 3 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 6 0 6 1 1 0 1 0 8 0
dma128 128 253 0 253 1 1 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 18 0 17 1 0 1 1 0 8 0
aobjpl 72 6 0 0 1 0 1 1 0 8 0
uaddrrnd 24 537 0 509 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 537 0 509 1 0 1 1 0 8 0
vmmpekpl 168 6496 0 6444 3 0 3 3 0 8 0
vmmpepl 168 43190 0 41521 87 0 87 87 0 357 7
vmsppl 488 536 0 509 5 0 5 5 0 8 1
rwobjpl 80 15367 0 14373 23 0 23 23 0 8 1
pdppl 4096 1081 0 1018 99 26 73 87 0 8 10
pvpl 32 9650 0 0 80 2 78 79 0 265 0
pmappl 256 536 0 509 3 0 3 3 0 8 1
extentpl 40 45 0 27 1 0 1 1 0 8 0
phpool 112 425 0 30 12 0 12 12 0 8 0
ddb{1}> machine ddbcpu 0
Stopped at x86_ipi_db+0x27: addq $0x8,%rsp
x86_ipi_db(ffffffff839ddff0) 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(ffffffff83a84f80) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff83a84f80) at __mp_lock+0x199 sys/kern/kern_lock.c:173
intr_handler(ffff80002ab9acb0,ffff800000079600) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:560
Xintr_ioapic_edge16_untramp() at Xintr_ioapic_edge16_untramp+0x18f
end of kernel
end trace frame: 0x75dc16d3ce00, count: 9
ddb{0}> trace
x86_ipi_db(ffffffff839ddff0) 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(ffffffff83a84f80) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff83a84f80) at __mp_lock+0x199 sys/kern/kern_lock.c:173
intr_handler(ffff80002ab9acb0,ffff800000079600) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:560
Xintr_ioapic_edge16_untramp() at Xintr_ioapic_edge16_untramp+0x18f
end of kernel
end trace frame: 0x75dc16d3ce00, count: -6
ddb{0}> machine ddbcpu 1
Stopped at db_enter+0x25: addq $0x8,%rsp
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff834c3a70) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff83504321,ffffffff835127f6,3bf,ffffffff8353b5ad) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80003c3d8c58,ffffffff834c027d) at refcnt_finalize+0x1e7 sys/kern/kern_synch.c:960
pppx_if_destroy(285b9c,ffff80003c3d8c50) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(285b9c,1,2000,ffff80002a2dd788) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff80002a364b50) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffa80715bae98,1,fffffa80097fd3a8,ffff80002a2dd788) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:298 [inline]
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b sys/kern/vfs_vnops.c:621
fdrop(fffffa806cf25670,ffff80002a2dd788) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffa806cf25670,ffff80002a2dd788) at closef+0x192 sys/kern/kern_descrip.c:1265
sys_closefrom(ffff80002a2dd788,ffff80002a364e20,ffff80002a364d70) at sys_closefrom+0x13c sys/kern/kern_descrip.c:1471
syscall(ffff80002a364e20) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a364e20) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcf0ef9e170, count: 1
ddb{1}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff834c3a70) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff83504321,ffffffff835127f6,3bf,ffffffff8353b5ad) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80003c3d8c58,ffffffff834c027d) at refcnt_finalize+0x1e7 sys/kern/kern_synch.c:960
pppx_if_destroy(285b9c,ffff80003c3d8c50) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(285b9c,1,2000,ffff80002a2dd788) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff80002a364b50) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffa80715bae98,1,fffffa80097fd3a8,ffff80002a2dd788) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:298 [inline]
vn_closefile(fffffa806cf25670,ffff80002a2dd788) at vn_closefile+0x12b sys/kern/vfs_vnops.c:621
fdrop(fffffa806cf25670,ffff80002a2dd788) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffa806cf25670,ffff80002a2dd788) at closef+0x192 sys/kern/kern_descrip.c:1265
sys_closefrom(ffff80002a2dd788,ffff80002a364e20,ffff80002a364d70) at sys_closefrom+0x13c sys/kern/kern_descrip.c:1471
syscall(ffff80002a364e20) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a364e20) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcf0ef9e170, count: -14