syzbot
panic: kernel diagnostic assertion "pg->wire_count != NUM" failed: file "/syzkaller/managers/kasan/kernel/sys/uvm/uvm_pa
Status:
upstream: reported on 2026/10/14 07:22
Reported-by: syzbot+dd08c36fd3364c299b17@syzkaller.appspotmail.com
First crash: 1d04h, last: 1d04h
Sample crash report:
panic: kernel WdiARaNgINGn:o SsPtLi c NaOsT sLerOWtEiRoEnD " pOgN- >SYwiSCrALeL_ c0 ou0 nEtX I!T =0 a0
" faStopped at savectx+0x9e: movl $0,%gs:0x688
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*262974 44274 0 0x2 0 0 ifconfig
savectx() at savectx+0x9e
end trace frame: 0x0, 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{0}>
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
*cpu1: kernel diagnostic assertion "pg->wire_count != 0" failed: file "/syzkaller/managers/kasan/kernel/sys/uvm/uvm_page.c", line 1207
ddb{0}> show kasan
kasan: no report recorded this boot
ddb{0}> trace
savectx() at savectx+0x9e
end trace frame: 0x0, count: -1
ddb{0}> show registers
rdi 0xffffffff854962a0 panicstr
rsi 0xffffffff84f7e4c0 __sancov_gen_cov_switch_values.22
rbp 0xffff800029919690
rbx 0
rdx 0
rcx 0xffffffff85093ff0 cpu_info_full_primary+0x1ff0
rax 0x31
r8 0xffff800029919560
r9 0x1
r10 0
r11 0xffffffff8154eec0 x86_bus_space_io_read_1
r12 0
r13 0
r14 0xffff80003bb72558
r15 0
rip 0xffffffff83dc934e savectx+0x9e
cs 0x8
rflags 0x46
rsp 0xffff800029919610
ss 0x10
savectx+0x9e: movl $0,%gs:0x688
ddb{0}> show proc
PROC (ifconfig) tid=262974 pid=44274 tcnt=1 stat=onproc
flags process=2<EXEC> proc=0
runpri=76, usrpri=77, slppri=32, nice=20
wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
forw=0xffffffffffffffff, list=0xffff800029884008,0xffff80003bb73cc0
process=0xffff8000298dc010 user=0xffff80002990e000, vmspace=0xffff800001829990
estcpu=27, cpticks=2, pctcpu=0.0, user=0, sys=1, intr=0
ddb{0}> ps
PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND
50273 211150 80579 0 2 0x2 0 sh
*44274 262974 58385 0 7 0x2 0 ifconfig
90601 121845 96936 0 3 0 0x80 nanoslp syz-executor
90601 469070 96936 0 3 0 0x4000080 fsleep syz-executor
90601 6708 96936 0 2 0 0x4000000 syz-executor
58385 364772 52259 0 3 0x100002 0x88 sigsusp sh
97342 209521 18576 0 3 0x2 0x80 wait syz-executor
52259 112343 18576 0 3 0x2 0x80 wait syz-executor
60015 319896 1 0 3 0x100003 0x80 ttyin getty
80579 334714 18576 0 2 0x10000002 0 syz-executor
35127 179471 18576 0 3 0x2 0x80 piperd syz-executor
62307 15928 18576 0 3 0x2 0x80 nanoslp syz-executor
36588 45255 18576 0 3 0x2 0x80 piperd syz-executor
96936 475494 18576 0 3 0x2 0x80 nanoslp syz-executor
18576 86249 1 0 3 0x2 0x80 wait syz-executor
77167 340747 0 0 3 0x14000 0x200 bored smr
64274 277153 0 0 2 0x14000 0x200 zerothread
89149 317201 0 0 3 0x14000 0x200 aiodoned aiodoned
69098 354694 0 0 3 0x14000 0x200 syncer update
73725 268000 0 0 3 0x14000 0x200 cleaner cleaner
67232 333619 0 0 2 0x14000 0x200 reaper
69080 184058 0 0 3 0x14000 0x200 pgdaemon pagedaemon
53927 399474 0 0 3 0x14000 0x200 bored viomb
34483 337488 0 0 3 0x14000 0x40000200 acpi0 acpi0
43561 299796 0 0 3 0x14000 0x40000200 idle1
13602 271307 0 0 3 0x14000 0x200 bored softnet1
93060 37287 0 0 3 0x14000 0x200 bored softnet0
48048 435842 0 0 3 0x14000 0x200 smrbar systqmp
71988 77579 0 0 3 0x14000 0x200 bored systq
33846 242509 0 0 3 0x14000 0x200 tmoslp softclockmp
89159 367230 0 0 3 0x14000 0x40000200 tmoslp softclock
22004 327897 0 0 3 0x14000 0x40000200 idle0
1 447119 0 0 3 0x2 0x80 wait init
0 0 -1 0 3 0x10000 0x200 scheduler swapper
ddb{0}> show all locks
CPU 0:
exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff854c3868)
#0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x632 sys/kern/subr_witness.c:1160
#1 mtx_enter+0x683 sys/kern/kern_lock.c:487
#2 uvm_pmr_freepages+0x225 sys/uvm/uvm_pmemrange.c:-1
#3 pmap_do_remove+0xe85 sys/arch/amd64/amd64/pmap.c:1982
#4 uvm_unmap_kill_entry_withlock+0x42f sys/uvm/uvm_map.c:1869
#5 uvm_unmap_remove+0x92a sys/uvm/uvm_map.c:2005
#6 uvmspace_exec+0x38c sys/uvm/uvm_map.c:3364
#7 sys_execve+0x1183 sys/kern/kern_exec.c:517
#8 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#8 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
#9 Xsyscall+0x128
Process 44274 (ifconfig) thread 0xffff80003bb72558 (262974)
exclusive rwlock amaplk r = 0 (0xffff800001af7be0)
#0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x632 sys/kern/subr_witness.c:1160
#1 rw_do_enter_write+0x53e sys/kern/kern_rwlock.c:320
#2 uvm_unmap_kill_entry_withlock+0x136 uvm_map_lock_entry sys/uvm/uvm_map.c:464 [inline]
#2 uvm_unmap_kill_entry_withlock+0x136 sys/uvm/uvm_map.c:1870
#3 uvm_unmap_remove+0x92a sys/uvm/uvm_map.c:2005
#4 uvmspace_exec+0x38c sys/uvm/uvm_map.c:3364
#5 sys_execve+0x1183 sys/kern/kern_exec.c:517
#6 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#6 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
#7 Xsyscall+0x128
exclusive rwlock vmmaplk r = 0 (0xffff800001829a90)
#0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x632 sys/kern/subr_witness.c:1160
#1 rw_do_enter_write+0x53e sys/kern/kern_rwlock.c:320
#2 vm_map_lock_ln+0x19f sys/uvm/uvm_map.c:5170
#3 uvmspace_exec+0x2e7 sys/uvm/uvm_map.c:3345
#4 sys_execve+0x1183 sys/kern/kern_exec.c:517
#5 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#5 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
#6 Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8558dbc0)
#0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x632 sys/kern/subr_witness.c:1160
#1 syscall+0x1048 mi_syscall sys/sys/syscall_mi.h:175 [inline]
#1 syscall+0x1048 sys/arch/amd64/amd64/trap.c:791
#2 Xsyscall+0x128
exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff854c3868)
#0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x632 sys/kern/subr_witness.c:1160
#1 mtx_enter+0x683 sys/kern/kern_lock.c:487
#2 uvm_pmr_freepages+0x225 sys/uvm/uvm_pmemrange.c:-1
#3 pmap_do_remove+0xe85 sys/arch/amd64/amd64/pmap.c:1982
#4 uvm_unmap_kill_entry_withlock+0x42f sys/uvm/uvm_map.c:1869
#5 uvm_unmap_remove+0x92a sys/uvm/uvm_map.c:2005
#6 uvmspace_exec+0x38c sys/uvm/uvm_map.c:3364
#7 sys_execve+0x1183 sys/kern/kern_exec.c:517
#8 syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#8 syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
#9 Xsyscall+0x128
Process 48048 (systqmp) thread 0xffff800045ffe298 (435842)
shared rwlock systqmp r = 0 (0xffffffff8540d1b8)
#0 witness_lock+0x632 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x632 sys/kern/subr_witness.c:1160
#1 taskq_thread+0x1ba sys/kern/kern_task.c:442
#2 proc_trampoline+0x10
ddb{0}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 11059 12175K 12394K 166960K 12164 0
pcb 18 24K 24K 166960K 22 0
rtable 233 15K 30K 166960K 395 0
pf 37 23K 26K 166960K 53 0
ifaddr 44 12K 13K 166960K 54 0
ifgroup 59 2K 2K 166960K 67 0
sysctl 3 1K 13K 166960K 7 0
counters 72 43K 43K 166960K 76 0
ioctlops 1 0K 194K 166960K 1498 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1333 86K 86K 166960K 1425 0
UFS quota 1 36K 36K 166960K 1 0
UFS mount 5 44K 44K 166960K 5 0
shm 2 2K 6K 166960K 5 0
VM map 2 1K 1K 166960K 2 0
sem 7 0K 0K 166960K 7 0
dirhash 12 2K 2K 166960K 12 0
ACPI 1692 195K 405K 166960K 12470 0
file desc 19 58K 121K 166960K 220 0
proc 100 50K 198K 166960K 646 0
subproc 90 11K 11K 166960K 108 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 20K 20K 166960K 1 0
in_multi 99 7K 8K 166960K 121 0
ether_multi 1 0K 0K 166960K 1 0
mrt 7 0K 0K 166960K 12 0
ISOFS mount 1 36K 36K 166960K 1 0
MSDOSFS mount 1 20K 20K 166960K 1 0
ttys 43 303K 303K 166960K 43 0
exec 22 5K 17K 166960K 422 0
fusefs mount 1 36K 36K 166960K 1 0
tdb 3 1K 1K 166960K 3 0
VM swap 14 124K 124K 166960K 15 0
UVM amap 456 177K 378K 166960K 3651 0
UVM aobj 6 4K 4K 166960K 7 0
pinsyscall 112 198K 386K 166960K 1445 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 0 0K 0K 166960K 2 0
NDP 19 0K 2K 166960K 35 0
temp 240 9275K 9470K 166960K 3912 0
kqueue 12 39K 84K 166960K 36 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 28 0 0 1 0 1 1 0 8 0
rtpcb 120 36 0 36 1 0 1 1 0 8 1
rtentry 176 132 0 56 6 0 6 6 0 8 0
unpcb 144 76 0 76 1 0 1 1 0 8 1
syncache 336 4 0 4 1 1 0 1 0 8 0
tcpcb 736 12 0 11 1 0 1 1 0 8 0
arp 136 22 0 10 1 0 1 1 0 8 0
inpcb 328 103 0 102 2 0 2 2 0 8 1
nd6 152 29 0 15 1 0 1 1 0 8 0
kcovpl 48 12 0 4 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 32 0 0 1 0 1 1 0 8 0
pfstkey 128 32 0 0 2 0 2 2 0 8 0
pfstate 448 32 0 0 4 0 4 4 0 8 0
pfrule 1360 24 0 19 2 1 1 2 0 8 0
art_heap8 4096 1 0 0 1 0 1 1 0 8 0
art_heap4 256 540 0 176 29 0 29 29 0 8 4
art_table 40 541 0 176 5 0 5 5 0 8 0
art_node 32 132 0 53 1 0 1 1 0 8 0
semapl 72 5 0 2 1 0 1 1 0 8 0
shmpl 120 4 0 2 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1649 0 175 93 0 93 93 0 8 0
ffsino 296 1649 0 175 114 0 114 114 0 8 0
nchpl 144 1903 0 192 64 0 64 64 0 8 0
vnodes 216 1787 0 0 100 0 100 100 0 8 0
namei 1024 7280 0 7280 6 2 4 4 0 8 4
percpumem 16 54 0 5 1 0 1 1 0 8 0
kstatmem 264 33 0 10 2 0 2 2 0 8 0
scxspl 216 7050 0 7050 6 3 3 3 1 8 3
plimitpl 152 44 0 33 1 0 1 1 0 8 0
sigapl 424 530 0 496 7 0 7 7 0 8 1
knotepl 120 54 0 0 2 0 2 2 0 8 0
kqueuepl 224 48 0 47 1 0 1 1 0 8 0
pipepl 344 145 0 118 3 0 3 3 0 8 0
fdescpl 528 514 0 498 3 0 3 3 0 8 0
filepl 160 2170 0 2022 12 0 12 12 0 8 2
lockfpl 104 15 0 15 1 0 1 1 0 8 1
lockfspl 48 7 0 7 1 0 1 1 0 8 1
sessionpl 144 30 0 27 1 0 1 1 0 8 0
pgrppl 48 42 0 31 1 0 1 1 0 8 0
ucredpl 104 131 0 128 1 0 1 1 0 8 0
zombiepl 144 499 0 496 1 0 1 1 0 8 0
processpl 1240 530 0 496 5 0 5 5 0 8 1
procpl 664 619 0 583 6 0 6 6 0 8 1
sosppl 176 2 0 2 1 0 1 1 0 8 1
sockpl 752 216 0 215 4 0 4 4 0 8 3
mcl8k 8192 2 0 0 1 0 1 1 0 8 0
mcl4k 4096 129 0 0 17 0 17 17 0 8 0
mcl2k 2048 24 0 0 3 0 3 3 0 8 0
mextrefs 64 24 0 0 1 0 1 1 0 8 0
mtagpl 96 3 0 0 1 0 1 1 0 8 0
mbufpl 256 242 0 0 16 0 16 16 0 8 0
bufpl 272 4936 0 106 322 0 322 322 0 8 0
anonpl 32 6014 0 0 49 0 49 49 0 222 0
amapchunkpl 152 10496 0 9996 20 0 20 20 0 158 0
amappl16 200 2295 0 2285 13 0 13 13 0 8 10
amappl15 192 7 0 7 1 1 0 1 0 8 0
amappl14 184 463 0 462 1 0 1 1 0 8 0
amappl13 176 127 0 126 1 0 1 1 0 8 0
amappl12 168 775 0 761 2 0 2 2 0 8 0
amappl11 160 4 0 4 1 1 0 1 0 8 0
amappl10 152 68 0 68 1 0 1 1 0 8 1
amappl9 144 273 0 273 1 1 0 1 0 8 0
amappl8 136 121 0 120 1 0 1 1 0 8 0
amappl7 128 152 0 150 1 0 1 1 0 8 0
amappl6 120 188 0 184 1 0 1 1 0 8 0
amappl5 112 106 0 106 1 0 1 1 0 8 1
amappl4 104 305 0 302 1 0 1 1 0 8 0
amappl3 96 1778 0 1736 3 0 3 3 0 8 1
amappl2 88 613 0 595 2 0 2 2 0 8 0
amappl1 80 10933 0 10826 15 0 15 15 0 8 7
amappl 88 2888 0 2803 4 0 4 4 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 6 0 2 1 0 1 1 0 8 0
uaddrrnd 24 514 0 497 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 514 0 497 1 0 1 1 0 8 0
vmmpekpl 168 6338 0 6303 3 0 3 3 0 8 0
vmmpepl 168 42858 0 42249 89 1 88 88 0 357 39
vmsppl 488 513 0 496 5 0 5 5 0 8 1
rwobjpl 80 16018 0 15634 24 0 24 24 0 8 4
pdppl 4096 1037 0 992 103 52 51 89 0 8 6
pvpl 32 22480 0 0 182 0 182 182 0 265 0
pmappl 256 513 0 496 3 0 3 3 0 8 1
extentpl 40 46 0 28 1 0 1 1 0 8 0
phpool 120 608 0 58 17 0 17 17 0 8 0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
savectx() at savectx+0x9e
end trace frame: 0x0, count: -1
ddb{0}> machine ddbcpu 1
Stopped at x86_ipi_db+0x19: leave
x86_ipi_db(ffff800028fd3ff0) at x86_ipi_db+0x19 sys/arch/amd64/amd64/db_interface.c:412
x86_ipi_handler() at x86_ipi_handler+0x112 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
x86_bus_space_io_read_4(b008,0) at x86_bus_space_io_read_4+0x29 sys/arch/amd64/amd64/bus_space.c:689
acpitimer_delay(1) at acpitimer_delay+0x2a2 acpitimer_read sys/dev/acpi/acpitimer.c:142 [inline]
acpitimer_delay(1) at acpitimer_delay+0x2a2 sys/dev/acpi/acpitimer.c:125
comcnputc(800,61) at comcnputc+0x342 sys/dev/ic/com.c:1274
cnputc(61) at cnputc+0xaf sys/dev/cons.c:218
db_putchar(61) at db_putchar+0x29f sys/ddb/db_output.c:155
kprintf() at kprintf+0x2afa sys/kern/subr_prf.c:1066
db_printf(ffffffff847d27c0) at db_printf+0x102 sys/kern/subr_prf.c:-1
panic(ffffffff847d2720) at panic+0x17d sys/kern/subr_prf.c:217
__assert(ffffffff8492a340,ffffffff8492a360,4b7,ffffffff8492ac80) at __assert+0x48
uvm_pageunwire(fffffd80082530c0) at uvm_pageunwire+0x1d8 sys/uvm/uvm_page.c:1206
uvm_fault_unwire_locked(ffff8000018293d8,f46efe63000,f46f0262000) at uvm_fault_unwire_locked+0x4a8 sys/uvm/uvm_fault.c:1794
end trace frame: 0xffff80002990d8b0, count: 0
ddb{1}> trace
x86_ipi_db(ffff800028fd3ff0) at x86_ipi_db+0x19 sys/arch/amd64/amd64/db_interface.c:412
x86_ipi_handler() at x86_ipi_handler+0x112 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
x86_bus_space_io_read_4(b008,0) at x86_bus_space_io_read_4+0x29 sys/arch/amd64/amd64/bus_space.c:689
acpitimer_delay(1) at acpitimer_delay+0x2a2 acpitimer_read sys/dev/acpi/acpitimer.c:142 [inline]
acpitimer_delay(1) at acpitimer_delay+0x2a2 sys/dev/acpi/acpitimer.c:125
comcnputc(800,61) at comcnputc+0x342 sys/dev/ic/com.c:1274
cnputc(61) at cnputc+0xaf sys/dev/cons.c:218
db_putchar(61) at db_putchar+0x29f sys/ddb/db_output.c:155
kprintf() at kprintf+0x2afa sys/kern/subr_prf.c:1066
db_printf(ffffffff847d27c0) at db_printf+0x102 sys/kern/subr_prf.c:-1
panic(ffffffff847d2720) at panic+0x17d sys/kern/subr_prf.c:217
__assert(ffffffff8492a340,ffffffff8492a360,4b7,ffffffff8492ac80) at __assert+0x48
uvm_pageunwire(fffffd80082530c0) at uvm_pageunwire+0x1d8 sys/uvm/uvm_page.c:1206
uvm_fault_unwire_locked(ffff8000018293d8,f46efe63000,f46f0262000) at uvm_fault_unwire_locked+0x4a8 sys/uvm/uvm_fault.c:1794
uvm_unmap_kill_entry_withlock(ffff8000018293d8,ffff8000017052a8,0) at uvm_unmap_kill_entry_withlock+0xc6 sys/uvm/uvm_map.c:1866
uvm_map_teardown(ffff8000018293d8) at uvm_map_teardown+0x1d7 uvm_map_addr_RBT_LEFT sys/uvm/uvm_map.h:-1 [inline]
uvm_map_teardown(ffff8000018293d8) at uvm_map_teardown+0x1d7 sys/uvm/uvm_map.c:2497
exit1(ffff80003bb722c0,0,0,1) at exit1+0xa58 sys/kern/kern_exit.c:262
sys_exit(ffff80003bb722c0,ffff80002990dc00,ffff80002990db60) at sys_exit+0x4a
syscall(ffff80002990dc00) at syscall+0x1089 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002990dc00) at syscall+0x1089 sys/arch/amd64/amd64/trap.c:791
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7776043af1d0, count: -20
ddb{1}>
Struck through repros no longer work on HEAD.