panic: kernel diagnostic assertion "rn != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/pipex.c", line 459
Stopped at db_enter+0x25: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
451397 13321 0 0 0 1 syz-executor
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8344b298) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff8348dc9d,ffffffff834aae98,1cb,ffffffff83449605) at __assert+0x29 sys/kern/subr_prf.c:-1
pipex_unlink_session_locked(ffff8000fffe2098) at pipex_unlink_session_locked+0x429
pipex_destroy_all_sessions(ffff800001606000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline]
pipex_destroy_all_sessions(ffff800001606000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:151
pppacclose(637f,1,2000,ffff8000373c5cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335
spec_close(ffff8000373c2910) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd805fbc9548,1,fffffd80097fd7b8,ffff8000373c5cb0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806b245540,ffff8000373c5cb0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806b245540,ffff8000373c5cb0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615
fdrop(fffffd806b245540,ffff8000373c5cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffd806b245540,ffff8000373c5cb0) at closef+0x192 sys/kern/kern_descrip.c:1265
fdfree(ffff8000373c5cb0) at fdfree+0x116 sys/kern/kern_descrip.c:1196
exit1(ffff8000373c5cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215
sys_exit(ffff8000373c5cb0,ffff8000373c2c80,ffff8000373c2bd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1
end trace frame: 0xffff8000373c2c70, count: 0
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{0}>
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
*cpu0: kernel diagnostic assertion "rn != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/pipex.c", line 459
ddb{0}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8344b298) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff8348dc9d,ffffffff834aae98,1cb,ffffffff83449605) at __assert+0x29 sys/kern/subr_prf.c:-1
pipex_unlink_session_locked(ffff8000fffe2098) at pipex_unlink_session_locked+0x429
pipex_destroy_all_sessions(ffff800001606000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline]
pipex_destroy_all_sessions(ffff800001606000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:151
pppacclose(637f,1,2000,ffff8000373c5cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335
spec_close(ffff8000373c2910) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd805fbc9548,1,fffffd80097fd7b8,ffff8000373c5cb0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806b245540,ffff8000373c5cb0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806b245540,ffff8000373c5cb0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615
fdrop(fffffd806b245540,ffff8000373c5cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffd806b245540,ffff8000373c5cb0) at closef+0x192 sys/kern/kern_descrip.c:1265
fdfree(ffff8000373c5cb0) at fdfree+0x116 sys/kern/kern_descrip.c:1196
exit1(ffff8000373c5cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215
sys_exit(ffff8000373c5cb0,ffff8000373c2c80,ffff8000373c2bd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff8000373c2c80) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff8000373c2c80) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x77ab69e85880, count: -16
ddb{0}> show registers
rdi 0
rsi 0x1
rbp 0xffff8000373c26e0
rbx 0xffffffff83954e07 cpu_info_full_primary+0x2e07
rdx 0
rcx 0xffff8000373c5cb0
rax 0xffffffff83953ff0 cpu_info_full_primary+0x1ff0
r8 0x101010101010101
r9 0x8080808080808080
r10 0xea20bdb58b2b01d6
r11 0x408ed2fccd278929
r12 0xffffffff83954c08 cpu_info_full_primary+0x2c08
r13 0
r14 0
r15 0x1
rip 0xffffffff83044655 db_enter+0x25
cs 0x8
rflags 0x246
rsp 0xffff8000373c26d0
ss 0x10
db_enter+0x25: addq $0x8,%rsp
ddb{0}> show proc
PROC (syz-executor) tid=328707 pid=9798 tcnt=0 stat=onproc
flags process=1008<EXITING,SINGLEEXIT> proc=2000<WEXIT>
runpri=32, usrpri=50, slppri=32, nice=20
wchan=0x0, wmesg=, ps_single=0xffff8000373c5cb0 scnt=-1 ecnt=1
forw=0xffffffffffffffff, list=0xffff8000373c4d20,0xffff8000fffe87f8
process=0xffff8000fffef038 user=0xffff8000373bd000, vmspace=0xfffffd806b8c39a8
estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb{0}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
97320 207556 33464 0 2 0 syz-executor
13321 451397 40721 0 7 0 syz-executor
13321 102046 40721 0 2 0x4000000 syz-executor
13321 85502 40721 0 2 0x4000000 syz-executor
13321 171802 40721 0 3 0x4000080 fsleep syz-executor
34322 384998 82461 0 2 0 syz-executor
34322 469674 82461 0 3 0x4000080 kqread syz-executor
22260 24863 15506 0 2 0xc80 syz-executor
22260 289799 15506 0 3 0x4000000 biowait syz-executor
22260 421474 15506 0 3 0x4000080 fsleep syz-executor
22260 45294 15506 0 3 0x4000080 fsleep syz-executor
47803 391278 34171 0 2 0xc80 syz-executor
47803 285252 34171 0 3 0x4000080 kqsel syz-executor
47803 103034 34171 0 3 0x4000080 fsleep syz-executor
93937 222314 5197 0 2 0xc80 syz-executor
93937 389513 5197 0 3 0x4000080 fsleep syz-executor
93937 501139 5197 0 3 0x4000080 kqsel syz-executor
94942 68443 66183 0 2 0 syz-executor
94942 296404 66183 0 3 0x4000080 fifor syz-executor
94942 242280 66183 0 3 0x4000080 fsleep syz-executor
83067 388321 23146 0 2 0x2 syz-executor
40721 274007 23146 0 3 0x82 nanoslp syz-executor
34171 237499 23146 0 3 0x82 nanoslp syz-executor
15506 198927 23146 0 3 0x82 nanoslp syz-executor
33464 38099 23146 0 2 0x2 syz-executor
5197 339245 23146 0 2 0xc82 syz-executor
82461 40938 23146 0 2 0xc82 syz-executor
66183 513285 23146 0 3 0x82 nanoslp syz-executor
23146 344139 80090 0 3 0x82 kqread syz-executor
80090 125835 29101 0 3 0x10008a sigsusp ksh
29101 370824 21369 0 3 0x98 kqread sshd-session
21369 94036 2061 0 3 0x92 kqread sshd-session
97586 44365 1 0 3 0x100083 ttyin getty
2061 169724 1 0 3 0x88 kqread sshd
79359 258757 89686 74 3 0x1100092 bpf pflogd
89686 150783 1 0 3 0x80 sbwait pflogd
32313 179765 54751 73 3 0x1100090 kqread syslogd
54751 457468 1 0 3 0x100082 sbwait syslogd
63469 419015 1 0 3 0x100080 kqread resolvd
69060 395358 11022 77 2 0x100012 dhcpleased
9083 214687 11022 77 3 0x100092 kqread dhcpleased
11022 418064 1 0 3 0x80 kqread dhcpleased
37132 507694 0 0 3 0x14200 bored smr
72060 137981 0 0 3 0x14200 pgzero zerothread
34624 196663 0 0 3 0x14200 aiodoned aiodoned
784 454808 0 0 3 0x14200 syncer update
53276 70094 0 0 3 0x14200 cleaner cleaner
73808 405651 0 0 3 0x14200 reaper reaper
29822 133111 0 0 3 0x14200 pgdaemon pagedaemon
88189 140336 0 0 3 0x14200 bored viomb
83301 482982 0 0 3 0x40014200 acpi0 acpi0
91379 319089 0 0 3 0x40014200 idle1
79642 405059 0 0 3 0x14200 bored softnet1
75890 297875 0 0 2 0x14200 softnet0
38379 158993 0 0 3 0x14200 bored systqmp
41759 69306 0 0 3 0x14200 bored systq
12953 282288 0 0 3 0x14200 tmoslp softclockmp
67541 101598 0 0 3 0x40014200 tmoslp softclock
55477 282716 0 0 3 0x40014200 idle0
1 188149 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{0}> show all locks
CPU 0:
exclusive mutex /syzkaller/managers/multicore/kernel/sys/net/pipex.c:78 r = 0 (0xffffffff839565e0)
#0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1 mtx_enter+0x4b4 sys/kern/kern_lock.c:487
#2 pipex_destroy_all_sessions+0x2f sys/net/pipex.c:144
#3 pppacclose+0x16f sys/net/if_pppx.c:1335
#4 spec_close+0x417 sys/kern/spec_vnops.c:-1
#5 VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
#6 vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
#6 vn_closefile+0x12b sys/kern/vfs_vnops.c:615
#7 fdrop+0x121 sys/kern/kern_descrip.c:1281
#8 closef+0x192 sys/kern/kern_descrip.c:1265
#9 fdfree+0x116 sys/kern/kern_descrip.c:1196
#10 exit1+0x576 sys/kern/kern_exit.c:215
#11 sys_exit+0x1a sys/kern/kern_exit.c:-1
#12 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#12 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#13 Xsyscall+0x128
Process 22260 (syz-executor) thread 0xffff8000fffe94e0 (289799)
exclusive rrwlock inode r = 0 (0xfffffd806c86d560)
#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:570
#5 vn_write+0x18f sys/kern/vfs_vnops.c:405
#6 dofilewritev+0x2bd sys/kern/sys_generic.c:384
#7 sys_write+0xa2 sys/kern/sys_generic.c:300
#8 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#8 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783
#9 Xsyscall+0x128
Process 75890 (softnet0) thread 0xffff8000ffffe298 (297875)
shared rwlock softnet0 r = 0 (0xffff80000002c078)
#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{0}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 11069 12314K 12408K 166960K 12234 0
pcb 18 12K 12K 166960K 21 0
rtable 244 8K 8K 166960K 368 0
pf 36 18K 21K 166960K 63 0
ifaddr 43 7K 7K 166960K 51 0
ifgroup 55 2K 2K 166960K 63 0
sysctl 1 1K 9K 166960K 5 0
counters 72 37K 38K 166960K 86 0
ioctlops 0 0K 4K 166960K 1500 0
iov 0 0K 16K 166960K 3 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1366 86K 86K 166960K 1487 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 5 0K 0K 166960K 5 0
dirhash 12 2K 2K 166960K 12 0
ACPI 1692 195K 286K 166960K 12470 0
file desc 18 65K 89K 166960K 197 0
sigio 0 0K 0K 166960K 3 0
proc 75 131K 164K 166960K 563 0
subproc 72 4K 4K 166960K 72 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 16K 16K 166960K 1 0
ip_moptions 0 0K 0K 166960K 10 0
in_multi 99 7K 7K 166960K 102 0
ether_multi 1 0K 0K 166960K 2 0
mrt 1 0K 0K 166960K 4 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 392 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 247 167K 181K 166960K 3778 0
UVM aobj 6 2K 2K 166960K 6 0
pinsyscall 43 86K 104K 166960K 1364 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 0 0K 0K 166960K 4 0
NDP 12 0K 2K 166960K 32 0
temp 38 9074K 9146K 166960K 4510 0
kqueue 15 24K 28K 166960K 37 0
SYN cache 2 16K 16K 166960K 2 0
ddb{0}> 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 40 0 36 1 0 1 1 0 8 0
rtentry 176 111 0 1 5 0 5 5 0 8 0
unpcb 144 70 0 48 1 0 1 1 0 8 0
syncache 336 3 0 3 1 0 1 1 0 8 1
tcpcb 736 19 0 15 1 0 1 1 0 8 0
arp 136 18 0 0 1 0 1 1 0 8 0
inpcb 328 165 0 157 6 0 6 6 0 8 5
nd6 152 24 0 0 1 0 1 1 0 8 0
kcovpl 48 8 0 0 1 0 1 1 0 8 0
ppxss 1192 8 0 7 1 0 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 1 0 0 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
pfrktable 1344 2 0 1 1 0 1 1 0 8 0
pftag 88 3 0 2 1 0 1 1 0 8 0
pfstitem 24 23 0 0 1 0 1 1 0 8 0
pfstkey 128 23 0 0 1 0 1 1 0 8 0
pfstate 448 23 0 0 3 0 3 3 0 8 0
pfrule 1360 23 0 17 2 1 1 2 0 8 0
art_heap8 4096 1 0 0 1 0 1 1 0 8 0
art_heap4 256 452 0 0 29 0 29 29 0 8 0
art_table 40 453 0 0 5 0 5 5 0 8 0
art_node 32 111 0 11 1 0 1 1 0 8 0
semupl 112 1 0 1 1 0 1 1 0 8 1
semapl 112 3 0 0 1 0 1 1 0 8 0
shmpl 112 3 0 0 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1691 0 218 93 0 93 93 0 8 0
ffsino 296 1691 0 218 114 0 114 114 0 8 0
nchpl 144 1965 0 258 64 0 64 64 0 8 0
rtmask 32 1 0 0 1 0 1 1 0 8 0
vnodes 216 1879 0 0 105 0 105 105 0 8 0
namei 1024 6033 0 6033 2 0 2 2 0 8 2
percpumem 16 58 0 7 1 0 1 1 0 8 0
kstatmem 264 34 0 8 3 0 3 3 0 8 1
scsiplug 72 1 0 1 1 0 1 1 0 8 1
scxspl 216 7031 0 7030 10 2 8 8 1 8 7
plimitpl 152 36 0 18 1 0 1 1 0 8 0
sigapl 424 518 0 470 7 0 7 7 0 8 1
knotepl 120 299 0 0 10 0 10 10 0 8 0
kqueuepl 224 46 0 30 2 0 2 2 0 8 0
pipepl 344 131 0 104 3 0 3 3 0 8 0
fdescpl 528 502 0 470 3 0 3 3 0 8 0
filepl 160 1972 0 1678 13 0 13 13 0 8 0
lockfpl 104 41 0 35 1 0 1 1 0 8 0
lockfspl 48 22 0 16 1 0 1 1 0 8 0
sessionpl 144 23 0 14 1 0 1 1 0 8 0
pgrppl 48 31 0 14 1 0 1 1 0 8 0
ucredpl 104 124 0 111 1 0 1 1 0 8 0
zombiepl 144 471 0 470 1 0 1 1 0 8 0
processpl 1232 518 0 470 5 0 5 5 0 8 1
procpl 664 646 0 585 6 0 6 6 0 8 0
sockpl 752 276 0 242 10 0 10 10 0 8 6
mcl64k 65536 3 0 0 1 0 1 1 0 8 0
mcl8k 8192 1 0 0 1 0 1 1 0 8 0
mcl4k 4096 107 0 0 14 0 14 14 0 8 0
mcl2k 2048 22 0 0 3 0 3 3 0 8 0
mtagpl 96 3 0 0 1 0 1 1 0 8 0
mbufpl 256 150 0 0 10 0 10 10 0 8 0
bufpl 280 2469 0 105 169 0 169 169 0 8 0
anonpl 32 7580 0 0 62 0 62 62 0 246 0
amapchunkpl 152 10677 0 10170 22 0 22 22 0 158 1
amappl16 200 2266 0 2208 15 0 15 15 0 8 11
amappl15 192 7 0 7 1 0 1 1 0 8 1
amappl14 184 440 0 439 1 0 1 1 0 8 0
amappl13 176 120 0 108 1 0 1 1 0 8 0
amappl12 168 752 0 722 2 0 2 2 0 8 0
amappl11 160 17 0 17 1 0 1 1 0 8 1
amappl10 152 108 0 94 1 0 1 1 0 8 0
amappl9 144 262 0 262 1 0 1 1 0 8 1
amappl8 136 105 0 103 1 0 1 1 0 8 0
amappl7 128 151 0 138 1 0 1 1 0 8 0
amappl6 120 184 0 183 1 0 1 1 0 8 0
amappl5 112 110 0 100 1 0 1 1 0 8 0
amappl4 104 312 0 291 1 0 1 1 0 8 0
amappl3 96 1923 0 1809 4 0 4 4 0 8 1
amappl2 88 539 0 476 2 0 2 2 0 8 0
amappl1 80 9602 0 9005 15 0 15 15 0 8 2
amappl 88 3030 0 2857 5 0 5 5 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 128 254 0 254 2 1 1 1 0 8 1
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 5 0 0 1 0 1 1 0 8 0
uaddrrnd 24 502 0 470 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 502 0 470 1 0 1 1 0 8 0
vmmpekpl 168 5910 0 5876 2 0 2 2 0 8 0
vmmpepl 168 40656 0 38670 96 0 96 96 0 357 8
vmsppl 488 501 0 470 5 0 5 5 0 8 1
rwobjpl 80 14850 0 13782 27 0 27 27 0 8 1
pdppl 4096 1011 0 940 99 22 77 83 0 8 6
pvpl 32 14940 0 0 121 0 121 121 0 265 0
pmappl 256 501 0 470 3 0 3 3 0 8 0
extentpl 40 45 0 27 1 0 1 1 0 8 0
phpool 112 269 0 25 8 0 8 8 0 8 0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8344b298) at panic+0x1e5 sys/kern/subr_prf.c:198
__assert(ffffffff8348dc9d,ffffffff834aae98,1cb,ffffffff83449605) at __assert+0x29 sys/kern/subr_prf.c:-1
pipex_unlink_session_locked(ffff8000fffe2098) at pipex_unlink_session_locked+0x429
pipex_destroy_all_sessions(ffff800001606000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline]
pipex_destroy_all_sessions(ffff800001606000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:151
pppacclose(637f,1,2000,ffff8000373c5cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335
spec_close(ffff8000373c2910) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd805fbc9548,1,fffffd80097fd7b8,ffff8000373c5cb0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806b245540,ffff8000373c5cb0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806b245540,ffff8000373c5cb0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615
fdrop(fffffd806b245540,ffff8000373c5cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1281
closef(fffffd806b245540,ffff8000373c5cb0) at closef+0x192 sys/kern/kern_descrip.c:1265
fdfree(ffff8000373c5cb0) at fdfree+0x116 sys/kern/kern_descrip.c:1196
exit1(ffff8000373c5cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215
sys_exit(ffff8000373c5cb0,ffff8000373c2c80,ffff8000373c2bd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff8000373c2c80) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff8000373c2c80) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x77ab69e85880, count: -16
ddb{0}> machine ddbcpu 1
Stopped at x86_ipi_db+0x27: addq $0x8,%rsp
x86_ipi_db(ffff8000299bdff0) 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
end of kernel
end trace frame: 0x73bc85324300, count: 12
ddb{1}> trace
x86_ipi_db(ffff8000299bdff0) 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
end of kernel
end trace frame: 0x73bc85324300, count: -3