syzbot
panic: kernel diagnostic assertion "pg->wire_count != NUM" failed: file "/syzkaller/managers/setuid/kernel/sys/uvm/uvm_p (2)
Status:
upstream: reported on 2026/09/23 21:45
Reported-by: syzbot+8aa5f9f38b4e5d3e3884@syzkaller.appspotmail.com
First crash: 19d, last: 19d
Sample crash report:
panic: WkAeRNrnINeGl: d SiPaL gnNosOTt LiOWc EasRsEDe rOtiNo nS Y"SpCgA-L>wiLr e9_1c o-1un6t5 8!1= 4404"4 0f aEiXlITed :0 a
Stopped at savectx+0xae: movl $0,%gs:0x688
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*247076 48312 32767 0x10 0 1 syz-executor
savectx() at savectx+0xae
end of kernel
end trace frame: 0x769c9d2ab930, 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}>
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
*cpu0: kernel diagnostic assertion "pg->wire_count != 0" failed: file "/syzkaller/managers/setuid/kernel/sys/uvm/uvm_page.c", line 1207
ddb{1}> show kasan
No such command
ddb{1}> trace
savectx() at savectx+0xae
end of kernel
end trace frame: 0x769c9d2ab930, count: -1
ddb{1}> show registers
rdi 0
rsi 0
rbp 0xffff80003278e180
rbx 0
rdx 0
rcx 0xffff80003c434fc0
rax 0x3c
r8 0xffff80003278e0b0
r9 0x1
r10 0x69b5987465fc6526
r11 0xc59451b695145781
r12 0
r13 0
r14 0xffff80003c434fc0
r15 0
rip 0xffffffff82a833ee savectx+0xae
cs 0x8
rflags 0x46
rsp 0xffff80003278e100
ss 0x10
savectx+0xae: movl $0,%gs:0x688
ddb{1}> show proc
PROC (syz-executor) tid=247076 pid=48312 tcnt=1 stat=onproc
flags process=10<SUGID> proc=0
runpri=32, usrpri=67, slppri=32, nice=20
wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
forw=0xffffffffffffffff, list=0xffff80003c435258,0xffff80003c3e4568
process=0xffff800045feb088 user=0xffff800032789000, vmspace=0xfffff8806d001d80
estcpu=17, cpticks=6, pctcpu=0.3, user=0, sys=6, intr=0
ddb{1}> ps
PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND
97014 137916 44674 0 2 0x10000002 0x80 syz-executor
94127 13317 30783 0 3 0x2 0 clonelk ifconfig
30783 167119 57462 0 3 0x100002 0x88 sigsusp sh
57462 73400 56880 0 3 0 0x80 wait syz-executor
56880 513884 44674 0 3 0x2 0x80 wait syz-executor
82910 142154 35404 0 3 0x2 0 clonelk ifconfig
35404 256916 63333 0 3 0x100002 0x88 sigsusp sh
63333 54660 73744 0 3 0 0x80 wait syz-executor
8268 307653 30996 0 3 0x2 0 clonelk ifconfig
73744 307734 44674 0 3 0x2 0x80 wait syz-executor
30996 513971 27526 0 3 0x100002 0x88 sigsusp sh
27526 143395 51146 0 3 0 0x80 wait syz-executor
51355 92944 98987 0 3 0x2 0 clonelk ifconfig
78984 34731 61024 0 3 0x2 0 clonelk ifconfig
98987 396062 98991 0 3 0x100002 0x88 sigsusp sh
51146 326760 44674 0 3 0x2 0x80 wait syz-executor
61024 8501 21554 0 3 0x100002 0x88 sigsusp sh
98991 413269 86098 0 3 0 0x80 wait syz-executor
86098 460472 44674 0 3 0x2 0x80 wait syz-executor
21554 164519 57676 0 3 0 0x80 wait syz-executor
57676 421779 44674 0 3 0x2 0x80 wait syz-executor
*48312 247076 6378 32767 7 0x10 0 syz-executor
6378 294085 44674 0 3 0x2 0x80 wait syz-executor
44674 460083 85509 0 2 0x2 0x80 syz-executor
85509 389344 87178 0 3 0x100002 0x88 sigsusp ksh
87178 315762 62758 0 3 0x10 0x88 kqread sshd-session
62758 310336 3818 0 3 0x12 0x80 kqread sshd-session
10258 119426 1 0 3 0x100003 0x80 ttyin getty
3818 482979 1 0 3 0 0x88 kqread sshd
29336 78883 89933 73 3 0x1100010 0x80 kqread syslogd
89933 221694 1 0 3 0x100002 0x80 sbwait syslogd
1734 220259 1 0 3 0x100000 0x80 kqread resolvd
80752 345450 93223 77 3 0x100012 0x80 kqread dhcpleased
32417 372447 93223 77 3 0x100012 0x80 kqread dhcpleased
93223 383444 1 0 3 0 0x80 kqread dhcpleased
86997 212762 0 0 3 0x14000 0x200 bored smr
37902 228080 0 0 2 0x14000 0x200 zerothread
26491 455220 0 0 3 0x14000 0x200 aiodoned aiodoned
52623 15014 0 0 3 0x14000 0x200 syncer update
66964 449670 0 0 3 0x14000 0x200 cleaner cleaner
5733 258302 0 0 2 0x14000 0x200 reaper
50647 85979 0 0 3 0x14000 0x200 pgdaemon pagedaemon
16714 357717 0 0 3 0x14000 0x200 bored viomb
15515 75879 0 0 3 0x14000 0x40000200 acpi0 acpi0
76078 461737 0 0 3 0x14000 0x40000200 idle1
1896 197780 0 0 3 0x14000 0x200 bored softnet1
71515 81985 0 0 3 0x14000 0x200 bored softnet0
71313 270402 0 0 3 0x14000 0x200 smrbar systqmp
19330 340154 0 0 3 0x14000 0x200 bored systq
59183 171114 0 0 3 0x14000 0x200 tmoslp softclockmp
36834 164419 0 0 3 0x14000 0x40000200 tmoslp softclock
43472 36293 0 0 3 0x14000 0x40000200 idle0
1 441009 0 0 3 0x2 0x80 wait init
0 0 -1 0 3 0x10000 0x200 scheduler swapper
ddb{1}> show all locks
CPU 1:
exclusive mutex &pmap->pm_mtx r = 0 (0xfffff8806d6b7110)
#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 pmap_do_remove+0xa9 rcr3 sys/arch/amd64/compile/SYZKALLER/obj/machine/cpufunc.h:139 [inline]
#2 pmap_do_remove+0xa9 pmap_map_ptes sys/arch/amd64/amd64/pmap.c:441 [inline]
#2 pmap_do_remove+0xa9 sys/arch/amd64/amd64/pmap.c:1834
#3 uvm_unmap_kill_entry_withlock+0x269 sys/uvm/uvm_map.c:1869
#4 uvm_map_teardown+0x117 uvm_map_addr_RBT_LEFT sys/uvm/uvm_map.h:-1 [inline]
#4 uvm_map_teardown+0x117 sys/uvm/uvm_map.c:2497
#5 exit1+0x71b sys/kern/kern_exit.c:260
#6 sys_exit+0x1a sys/kern/kern_exit.c:-1
#7 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#7 syscall+0xb17 sys/arch/amd64/amd64/trap.c:791
#8 Xsyscall+0x128
Process 71313 (systqmp) thread 0xffff800045ffe000 (270402)
shared rwlock systqmp r = 0 (0xffffffff839c26c8)
#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 11037 12007K 12034K 166960K 12155 0
pcb 17 12K 12K 166960K 17 0
rtable 127 3K 7K 166960K 476 0
pf 21 15K 16K 166960K 39 0
ifaddr 22 3K 7K 166960K 60 0
ifgroup 30 1K 2K 166960K 66 0
sysctl 1 1K 9K 166960K 5 0
counters 60 35K 37K 166960K 78 0
ioctlops 0 0K 4K 166960K 37 0
iov 0 0K 3K 166960K 9 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1314 83K 83K 166960K 1549 0
UFS quota 1 32K 32K 166960K 1 0
UFS mount 5 36K 36K 166960K 5 0
shm 2 1K 5K 166960K 7 0
VM map 2 1K 1K 166960K 2 0
sem 10 0K 0K 166960K 11 0
dirhash 12 2K 2K 166960K 21 0
ACPI 1692 195K 286K 166960K 12470 0
file desc 27 101K 121K 166960K 419 0
proc 93 180K 180K 166960K 683 0
subproc 81 5K 6K 166960K 261 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 16K 16K 166960K 1 0
ip_moptions 0 0K 0K 166960K 50 0
in_multi 44 2K 6K 166960K 150 0
ether_multi 1 0K 0K 166960K 2 0
mrt 0 0K 0K 166960K 5 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 450 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 221 166K 188K 166960K 4910 0
UVM aobj 13 2K 2K 166960K 14 0
pinsyscall 48 96K 112K 166960K 1633 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 0 0K 0K 166960K 9 0
NDP 6 0K 2K 166960K 39 0
temp 43 9119K 9138K 166960K 4583 0
kqueue 13 20K 31K 166960K 62 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 54 0 51 1 0 1 1 0 8 0
rtentry 176 156 0 101 6 0 6 6 0 8 1
unpcb 144 110 0 95 1 0 1 1 0 8 0
syncache 336 6 0 6 1 0 1 1 0 8 1
tcpqe 32 2 0 2 1 0 1 1 0 8 1
tcpcb 736 93 0 88 4 0 4 4 0 8 3
arp 136 26 0 18 1 0 1 1 0 8 0
ipq 40 3 0 1 1 0 1 1 0 8 0
ipqe 40 4 0 2 1 0 1 1 0 8 0
inpcb 328 256 0 243 4 0 4 4 0 8 2
ip6q 80 1 0 0 1 0 1 1 0 8 0
ip6af 40 1 0 0 1 0 1 1 0 8 0
nd6 152 37 0 28 1 0 1 1 0 8 0
kcovpl 48 29 0 20 1 0 1 1 0 8 0
art_heap8 4096 1 0 0 1 0 1 1 0 8 0
art_heap4 256 644 0 367 32 1 31 32 0 8 8
art_table 40 645 0 367 6 0 6 6 0 8 1
art_node 32 156 0 97 1 0 1 1 0 8 0
sysvmsgpl 40 3 0 2 1 0 1 1 0 8 0
semupl 112 1 0 1 1 0 1 1 0 8 1
semapl 72 9 0 1 1 0 1 1 0 8 0
shmpl 120 11 0 1 1 0 1 1 0 8 0
dirhash 1024 23 0 6 3 0 3 3 0 8 0
dino2pl 256 1788 0 299 94 0 94 94 0 8 0
ffsino 296 1788 0 299 115 0 115 115 0 8 0
nchpl 144 2203 0 480 64 0 64 64 0 8 0
vnodes 216 2058 0 0 115 0 115 115 0 8 0
namei 1024 8180 0 8180 3 1 2 2 0 8 2
percpumem 16 55 0 9 1 0 1 1 0 8 0
kstatmem 264 33 0 18 2 0 2 2 0 8 0
scxspl 216 7470 0 7470 3 2 1 2 1 8 1
plimitpl 152 217 0 191 2 0 2 2 0 8 0
sigapl 424 670 0 612 7 0 7 7 0 8 0
knotepl 120 364 0 0 12 0 12 12 0 8 0
kqueuepl 224 134 0 125 5 0 5 5 0 8 4
pipepl 344 197 0 170 4 0 4 4 0 8 0
fdescpl 528 654 0 615 3 0 3 3 0 8 0
filepl 160 2757 0 2548 14 0 14 14 0 8 3
lockfpl 104 146 0 144 1 0 1 1 0 8 0
lockfspl 48 21 0 19 1 0 1 1 0 8 0
sessionpl 144 54 0 37 1 0 1 1 0 8 0
pgrppl 48 84 0 59 1 0 1 1 0 8 0
ucredpl 104 317 0 303 1 0 1 1 0 8 0
zombiepl 144 617 0 612 1 0 1 1 0 8 0
processpl 1240 670 0 612 5 0 5 5 0 8 0
procpl 664 904 0 846 7 0 7 7 0 8 1
sosppl 176 1 0 1 1 0 1 1 0 8 1
sockpl 752 422 0 391 7 0 7 7 0 8 3
mcl64k 65536 3 0 0 1 0 1 1 0 8 0
mcl16k 16384 1 0 0 1 0 1 1 0 8 0
mcl8k 8192 1 0 0 1 0 1 1 0 8 0
mcl4k 4096 123 0 0 16 0 16 16 0 8 0
mcl2k 2048 19 0 0 3 0 3 3 0 8 0
mextrefs 64 19 0 0 1 0 1 1 0 8 0
mtagpl 96 3 0 0 1 0 1 1 0 8 0
mbufpl 256 219 0 0 14 0 14 14 0 8 0
bufpl 272 5049 0 102 330 0 330 330 0 8 0
anonpl 32 10252 0 0 83 0 83 83 0 247 0
amapchunkpl 152 14389 0 13697 34 0 34 34 0 158 1
amappl16 200 2095 0 2082 14 4 10 14 0 8 7
amappl15 192 8 0 8 1 1 0 1 0 8 0
amappl14 184 470 0 464 1 0 1 1 0 8 0
amappl13 176 125 0 115 1 0 1 1 0 8 0
amappl12 168 904 0 875 2 0 2 2 0 8 0
amappl11 160 9 0 9 1 1 0 1 0 8 0
amappl10 152 59 0 49 1 0 1 1 0 8 0
amappl9 144 291 0 291 1 1 0 1 0 8 0
amappl8 136 115 0 107 1 0 1 1 0 8 0
amappl7 128 176 0 165 1 0 1 1 0 8 0
amappl6 120 203 0 191 1 0 1 1 0 8 0
amappl5 112 94 0 87 1 0 1 1 0 8 0
amappl4 104 294 0 277 1 0 1 1 0 8 0
amappl3 96 2435 0 2348 4 1 3 3 0 8 0
amappl2 88 764 0 690 3 0 3 3 0 8 1
amappl1 80 12315 0 11730 16 0 16 16 0 8 2
amappl 88 4100 0 3947 5 0 5 5 0 92 0
uvmvnodes 80 102 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 13 0 1 1 0 1 1 0 8 0
uaddrrnd 24 654 0 614 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 654 0 614 1 0 1 1 0 8 0
vmmpekpl 168 7692 0 7629 4 0 4 4 0 8 0
vmmpepl 168 52192 0 50283 102 0 102 102 0 357 13
vmsppl 488 653 0 613 7 1 6 6 0 8 0
rwobjpl 80 17953 0 16922 25 0 25 25 0 8 1
pdppl 4096 1315 0 1226 117 26 91 95 0 8 2
pvpl 32 30632 0 0 249 1 248 248 0 265 0
pmappl 256 653 0 613 4 1 3 3 0 8 0
extentpl 40 45 0 27 1 0 1 1 0 8 0
phpool 112 628 0 31 18 0 18 18 0 8 0
ddb{1}> machine ddbcpu 0
Stopped at x86_ipi_db+0x27: addq $0x8,%rsp
x86_ipi_db(ffffffff839cbff0) 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(ffffffff83a496c0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff83a496c0) at __mp_lock+0x192 sys/kern/kern_lock.c:173
softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83
dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:862
Xsoftclock() at Xsoftclock+0x27
cnputc(20) at cnputc+0x67 sys/dev/cons.c:218
db_putchar(66) at db_putchar+0x126 db_force_whitespace sys/ddb/db_output.c:102 [inline]
db_putchar(66) at db_putchar+0x126 sys/ddb/db_output.c:153
kprintf() at kprintf+0x2a75 sys/kern/subr_prf.c:-1
db_printf(ffffffff834a388e) at db_printf+0x9b sys/kern/subr_prf.c:-1
panic(ffffffff834ca420) at panic+0x103 sys/kern/subr_prf.c:217
__assert(ffffffff83506a03,ffffffff8345f0fa,4b7,ffffffff8345f12f) at __assert+0x29 sys/kern/subr_prf.c:-1
uvm_pageunwire(fffff880091a28c0) at uvm_pageunwire+0x17d sys/uvm/uvm_page.c:1206
end trace frame: 0xffff80003c407b70, count: 0
ddb{0}> trace
x86_ipi_db(ffffffff839cbff0) 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(ffffffff83a496c0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff83a496c0) at __mp_lock+0x192 sys/kern/kern_lock.c:173
softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83
dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:862
Xsoftclock() at Xsoftclock+0x27
cnputc(20) at cnputc+0x67 sys/dev/cons.c:218
db_putchar(66) at db_putchar+0x126 db_force_whitespace sys/ddb/db_output.c:102 [inline]
db_putchar(66) at db_putchar+0x126 sys/ddb/db_output.c:153
kprintf() at kprintf+0x2a75 sys/kern/subr_prf.c:-1
db_printf(ffffffff834a388e) at db_printf+0x9b sys/kern/subr_prf.c:-1
panic(ffffffff834ca420) at panic+0x103 sys/kern/subr_prf.c:217
__assert(ffffffff83506a03,ffffffff8345f0fa,4b7,ffffffff8345f12f) at __assert+0x29 sys/kern/subr_prf.c:-1
uvm_pageunwire(fffff880091a28c0) at uvm_pageunwire+0x17d sys/uvm/uvm_page.c:1206
uvm_fault_unwire_locked(fffff8800b1f71e8,66efc6bc000,66efc6bd000) at uvm_fault_unwire_locked+0x33a sys/uvm/uvm_fault.c:1790
uvm_unmap_kill_entry_withlock(fffff8800b1f71e8,fffff8806d1f1780,0) at uvm_unmap_kill_entry_withlock+0x81 sys/uvm/uvm_map.c:1866
uvm_map_teardown(fffff8800b1f71e8) at uvm_map_teardown+0x117 uvm_map_addr_RBT_LEFT sys/uvm/uvm_map.h:-1 [inline]
uvm_map_teardown(fffff8800b1f71e8) at uvm_map_teardown+0x117 sys/uvm/uvm_map.c:2497
exit1(ffff80003c435788,0,0,1) at exit1+0x71b sys/kern/kern_exit.c:260
sys_exit(ffff80003c435788,ffff80003c407db0,ffff80003c407d00) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff80003c407db0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c407db0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x769c9d2ab960, count: -21
ddb{0}> machine ddbcpu 1
Stopped at savectx+0xae: movl $0,%gs:0x688
savectx() at savectx+0xae
end of kernel
end trace frame: 0x769c9d2ab930, count: 14
ddb{1}> trace
savectx() at savectx+0xae
end of kernel
end trace frame: 0x769c9d2ab930, count: -1
Struck through repros no longer work on HEAD.