login: panic: mutex 0xfffffd806e89a870 not held in knote_dequeue
Stopped at db_enter+0x18: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*155725 6868 0 0 0x4000000 0 syz-executor7930
319424 40632 0 0x14000 0x200 1 zerothread
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399
panic(ffffffff82460c20) at panic+0x177 sys/kern/subr_prf.c:202
knote_dequeue(fffffd806ecef070) at knote_dequeue+0x12b sys/kern/kern_event.c:1860
filt_timermodify(ffff800021268e30,fffffd806ecef070) at filt_timermodify+0x6f sys/kern/kern_event.c:479
kqueue_register(fffffd806e89a870,ffff800021268e30,ffff8000211b2a88) at kqueue_register+0xa89 filter_modify sys/kern/kern_event.c:662 [inline]
kqueue_register(fffffd806e89a870,ffff800021268e30,ffff8000211b2a88) at kqueue_register+0xa89 sys/kern/kern_event.c:1125
sys_kevent(ffff8000211b2a88,ffff800021269048,ffff800021269090) at sys_kevent+0x214 sys/kern/kern_event.c:887
syscall(ffff800021269110) at syscall+0x5bf mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800021269110) at syscall+0x5bf sys/arch/amd64/amd64/trap.c:587
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x564680c1880, count: 7
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ddb{0}>
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
*cpu0: mutex 0xfffffd806e89a870 not held in knote_dequeue
ddb{0}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399
panic(ffffffff82460c20) at panic+0x177 sys/kern/subr_prf.c:202
knote_dequeue(fffffd806ecef070) at knote_dequeue+0x12b sys/kern/kern_event.c:1860
filt_timermodify(ffff800021268e30,fffffd806ecef070) at filt_timermodify+0x6f sys/kern/kern_event.c:479
kqueue_register(fffffd806e89a870,ffff800021268e30,ffff8000211b2a88) at kqueue_register+0xa89 filter_modify sys/kern/kern_event.c:662 [inline]
kqueue_register(fffffd806e89a870,ffff800021268e30,ffff8000211b2a88) at kqueue_register+0xa89 sys/kern/kern_event.c:1125
sys_kevent(ffff8000211b2a88,ffff800021269048,ffff800021269090) at sys_kevent+0x214 sys/kern/kern_event.c:887
syscall(ffff800021269110) at syscall+0x5bf mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800021269110) at syscall+0x5bf sys/arch/amd64/amd64/trap.c:587
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x564680c1880, count: -8
ddb{0}> show registers
rdi 0
rsi 0x1
rbp 0xffff800021268b80
rbx 0xffffffff8275dbf7 cpu_info_full_primary+0x2bf7
rdx 0x8b
rcx 0x2
rax 0x3a
r8 0xffffffff816e1c04 kprintf+0x144
r9 0x1
r10 0xdc56e1594e5dfa95
r11 0xf24ae5dbeab2f647
r12 0xffffffff8275d9f8 cpu_info_full_primary+0x29f8
r13 0
r14 0
r15 0x1
rip 0xffffffff81910f78 db_enter+0x18
cs 0x8
rflags 0x246
rsp 0xffff800021268b70
ss 0x10
db_enter+0x18: addq $0x8,%rsp
ddb{0}> show proc
PROC (syz-executor7930) pid=155725 stat=onproc
flags process=0 proc=4000000<THREAD>
pri=32, usrpri=52, nice=20
forw=0xffffffffffffffff, list=0xffff8000211b22a8,0xffff8000211b3278
process=0xffff800021224880 user=0xffff800021264000, vmspace=0xfffffd807f0098a0
estcpu=36, cpticks=0, pctcpu=0.0
user=0, sys=0, intr=0
ddb{0}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
6868 162702 23117 0 3 0x80 nanoslp syz-executor7930
* 6868 155725 23117 0 7 0x4000000 syz-executor7930
6868 36273 23117 0 2 0x4000000 syz-executor7930
96415 241950 16533 0 2 0 syz-executor7930
96415 341938 16533 0 3 0x4000080 fsleep syz-executor7930
96415 249725 16533 0 2 0x4000000 syz-executor7930
16533 520432 41296 0 3 0x80 nanoslp syz-executor7930
23117 434765 41296 0 3 0x80 nanoslp syz-executor7930
41296 163560 21851 0 3 0x82 nanoslp syz-executor7930
21851 449004 5399 0 3 0x10008a sigsusp ksh
5399 9273 74993 0 3 0x92 select sshd
44833 32472 1 0 3 0x100083 ttyin getty
74993 127584 1 0 3 0x80 select sshd
28113 487556 69736 74 3 0x100092 bpf pflogd
69736 21365 1 0 3 0x80 netio pflogd
30448 372728 94224 73 3 0x100090 kqread syslogd
94224 305917 1 0 3 0x100082 netio syslogd
93312 518488 1 77 3 0x100090 poll dhclient
15846 437395 1 0 3 0x80 poll dhclient
96061 135682 0 0 3 0x14200 bored smr
40632 319424 0 0 7 0x14200 zerothread
94254 461080 0 0 3 0x14200 aiodoned aiodoned
44057 2900 0 0 3 0x14200 syncer update
36998 380132 0 0 3 0x14200 cleaner cleaner
84325 328959 0 0 3 0x14200 reaper reaper
35038 351601 0 0 3 0x14200 pgdaemon pagedaemon
51403 214450 0 0 3 0x14200 bored crynlk
50086 448154 0 0 3 0x14200 bored crypto
30097 464327 0 0 3 0x14200 bored viomb
60207 118260 0 0 3 0x40014200 acpi0 acpi0
48566 353279 0 0 3 0x40014200 idle1
62493 463075 0 0 3 0x14200 bored softnet
96662 496337 0 0 3 0x14200 bored systqmp
70361 236130 0 0 3 0x14200 bored systq
63745 67605 0 0 3 0x40014200 bored softclock
27601 255978 0 0 3 0x40014200 idle0
1 8539 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{0}> show all locks
CPU 1:
exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff8296da20)
#0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182
#1 mtx_enter_try+0x100
#2 mtx_enter+0x4b sys/kern/kern_lock.c:266
#3 uvm_pagezero_thread+0x191 sys/uvm/uvm_pmemrange.c:2185
#4 proc_trampoline+0x1c
Process 6868 (syz-executor7930) thread 0xffff8000211b2a88 (155725)
exclusive kernel_lock &kernel_lock r = 1 (0xffffffff827d4278)
#0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182
#1 syscall+0x439 mi_syscall sys/sys/syscall_mi.h:93 [inline]
#1 syscall+0x439 sys/arch/amd64/amd64/trap.c:587
#2 Xsyscall+0x128
ddb{0}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 10112 6476K 6477K 78643K 11202 0
pcb 13 8K 8K 78643K 13 0
rtable 61 2K 2K 78643K 119 0
ifaddr 29 8K 8K 78643K 30 0
counters 40 33K 33K 78643K 40 0
ioctlops 0 0K 4K 78643K 1467 0
mount 1 1K 1K 78643K 1 0
log 0 0K 0K 78643K 1 0
vnodes 1183 74K 75K 78643K 1188 0
UFS quota 1 32K 32K 78643K 1 0
UFS mount 5 36K 36K 78643K 5 0
shm 2 1K 1K 78643K 2 0
VM map 2 1K 1K 78643K 2 0
sem 2 0K 0K 78643K 2 0
dirhash 12 2K 2K 78643K 12 0
ACPI 1697 195K 286K 78643K 12598 0
file desc 1 0K 0K 78643K 1 0
proc 59 63K 71K 78643K 357 0
NFS srvsock 1 0K 0K 78643K 1 0
NFS daemon 1 16K 16K 78643K 1 0
in_multi 11 0K 0K 78643K 11 0
ether_multi 1 0K 0K 78643K 1 0
ISOFS mount 1 32K 32K 78643K 1 0
MSDOSFS mount 1 16K 16K 78643K 1 0
ttys 19 95K 95K 78643K 19 0
exec 0 0K 2K 78643K 298 0
pagedep 1 8K 8K 78643K 1 0
inodedep 1 32K 32K 78643K 1 0
newblk 1 0K 0K 78643K 1 0
VM swap 7 26K 26K 78643K 7 0
UVM amap 98 4K 5K 78643K 1908 0
UVM aobj 3 2K 2K 78643K 3 0
memdesc 1 4K 4K 78643K 1 0
crypto data 1 1K 1K 78643K 1 0
NDP 4 0K 0K 78643K 4 0
temp 23 3973K 4037K 78643K 1755 0
kqueue 6 3K 5K 78643K 170 0
SYN cache 2 16K 16K 78643K 2 0
ddb{0}> show all pools
Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
plcache 128 22 0 0 1 0 1 1 0 8 0
rtpcb 120 15 0 13 1 0 1 1 0 8 0
rtentry 112 23 0 1 1 0 1 1 0 8 0
unpcb 120 29 0 19 1 0 1 1 0 8 0
syncache 296 5 0 5 2 1 1 1 0 8 1
tcpcb 736 8 0 5 1 0 1 1 0 8 0
arp 120 2 0 0 1 0 1 1 0 8 0
inpcb 304 28 0 23 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 8 0 2 1 0 1 1 0 8 0
pfstkey 112 8 0 2 1 0 1 1 0 8 0
pfstate 320 8 0 2 1 0 1 1 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 97 0 0 7 0 7 7 0 8 0
art_table 32 98 0 0 1 0 1 1 0 8 0
art_node 16 22 0 2 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1446 0 57 87 0 87 87 0 8 0
ffsino 272 1446 0 57 93 0 93 93 0 8 0
nchpl 144 1665 0 117 58 0 58 58 0 8 0
uvmvnodes 72 1456 0 0 27 0 27 27 0 8 0
vnodes 224 1456 0 0 86 0 86 86 0 8 0
namei 1024 3949 0 3949 2 1 1 1 0 8 1
percpumem 16 32 0 0 1 0 1 1 0 8 0
scxspl 216 3851 0 3851 10 9 1 8 0 8 1
plimitpl 152 14 0 8 1 0 1 1 0 8 0
sigapl 424 265 0 232 4 0 4 4 0 8 0
futexpl 56 134 0 133 1 0 1 1 0 8 0
knotepl 112 21 0 0 1 0 1 1 0 8 0
kqueuepl 216 85 0 82 1 0 1 1 0 8 0
pipepl 336 64 0 60 2 1 1 1 0 8 0
fdescpl 496 249 0 232 3 0 3 3 0 8 0
filepl 152 1079 0 1030 2 0 2 2 0 8 0
lockfpl 104 5 0 4 1 0 1 1 0 8 0
lockfspl 48 3 0 2 1 0 1 1 0 8 0
sessionpl 144 18 0 9 1 0 1 1 0 8 0
pgrppl 48 18 0 9 1 0 1 1 0 8 0
ucredpl 96 62 0 53 1 0 1 1 0 8 0
zombiepl 144 232 0 232 2 1 1 1 0 8 1
processpl 1080 265 0 232 3 0 3 3 0 8 0
procpl 672 341 0 304 4 0 4 4 0 8 0
sockpl 480 72 0 55 4 1 3 3 0 8 0
mcl8k 8192 3 0 0 1 0 1 1 0 8 0
mcl4k 4096 3 0 0 1 0 1 1 0 8 0
mcl2k 2048 86 0 0 10 0 10 10 0 8 0
mtagpl 96 1 0 0 1 0 1 1 0 8 0
mbufpl 256 106 0 0 6 0 6 6 0 8 0
bufpl 280 1991 0 93 136 0 136 136 0 8 0
anonpl 24 36395 0 33899 19 3 16 16 0 186 0
amapchunkpl 152 3717 0 3535 10 2 8 8 0 158 1
amappl16 200 74 0 70 2 1 1 1 0 8 0
amappl15 192 51 0 46 1 0 1 1 0 8 0
amappl13 176 14 0 13 2 1 1 1 0 8 0
amappl12 168 5 0 5 1 1 0 1 0 8 0
amappl11 160 40 0 28 1 0 1 1 0 8 0
amappl10 152 31 0 24 1 0 1 1 0 8 0
amappl9 144 204 0 204 2 1 1 1 0 8 1
amappl8 136 230 0 223 1 0 1 1 0 8 0
amappl7 128 43 0 42 1 0 1 1 0 8 0
amappl6 120 84 0 74 1 0 1 1 0 8 0
amappl5 112 130 0 120 1 0 1 1 0 8 0
amappl4 104 524 0 498 1 0 1 1 0 8 0
amappl3 96 134 0 123 1 0 1 1 0 8 0
amappl2 88 292 0 259 1 0 1 1 0 8 0
amappl1 80 7179 0 6790 9 0 9 9 0 8 0
amappl 88 1704 0 1623 2 0 2 2 0 92 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 64 2 0 0 1 0 1 1 0 8 0
uaddrrnd 24 249 0 232 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 249 0 232 1 0 1 1 0 8 0
vmmpekpl 168 5694 0 5677 1 0 1 1 0 8 0
vmmpepl 168 22428 0 21464 43 0 43 43 0 357 1
vmsppl 368 248 0 232 2 0 2 2 0 8 0
rwobjpl 56 6774 0 6243 9 1 8 8 0 8 0
pdppl 4096 505 0 464 59 18 41 41 0 8 0
pvpl 32 108737 0 104309 40 3 37 37 0 265 1
pmappl 232 248 0 232 1 0 1 1 0 8 0
extentpl 40 58 0 40 1 0 1 1 0 8 0
phpool 112 280 0 23 8 0 8 8 0 8 0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399
panic(ffffffff82460c20) at panic+0x177 sys/kern/subr_prf.c:202
knote_dequeue(fffffd806ecef070) at knote_dequeue+0x12b sys/kern/kern_event.c:1860
filt_timermodify(ffff800021268e30,fffffd806ecef070) at filt_timermodify+0x6f sys/kern/kern_event.c:479
kqueue_register(fffffd806e89a870,ffff800021268e30,ffff8000211b2a88) at kqueue_register+0xa89 filter_modify sys/kern/kern_event.c:662 [inline]
kqueue_register(fffffd806e89a870,ffff800021268e30,ffff8000211b2a88) at kqueue_register+0xa89 sys/kern/kern_event.c:1125
sys_kevent(ffff8000211b2a88,ffff800021269048,ffff800021269090) at sys_kevent+0x214 sys/kern/kern_event.c:887
syscall(ffff800021269110) at syscall+0x5bf mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800021269110) at syscall+0x5bf sys/arch/amd64/amd64/trap.c:587
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x564680c1880, count: -8
ddb{0}> machine ddbcpu 1
Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp
x86_ipi_db(ffff800020d58ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:353
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x4f sys/dev/kcov.c:149
uvm_pagezero_thread(ffff8000211b2548) at uvm_pagezero_thread+0xb0 sys/uvm/uvm_pmemrange.c:2171
end trace frame: 0x0, count: 10
ddb{1}> trace
x86_ipi_db(ffff800020d58ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:353
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x4f sys/dev/kcov.c:149
uvm_pagezero_thread(ffff8000211b2548) at uvm_pagezero_thread+0xb0 sys/uvm/uvm_pmemrange.c:2171
end trace frame: 0x0, count: -5
ddb{1}>