panic: acquiring blockable sleep lock with spinlock or critical section held (rwlock) vmmaplk

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 1a46f257 Only print valid rdomains. '-1' is used as defaul..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=10af6490100000
kernel config: https://syzkaller.appspot.com/x/.config?x=bf87b6915a88cd0d
dashboard link: https://syzkaller.appspot.com/bug?extid=f43e98f1697272e6e63a

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+f43e98...@syzkaller.appspotmail.com

panic: acquiring blockable sleep lock with spinlock or critical section held (rwlock) vmmaplk
Stopped at db_enter+0x18: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
* 60436 3135 0 0x14000 0x200 1K reaper
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff8220b555) at panic+0x15c sys/kern/subr_prf.c:207
witness_checkorder(ffffffff8263e458,1,0) at witness_checkorder+0x10e0 sys/kern/subr_witness.c:821
rw_enter_read(ffffffff8263e448) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:111
uvmfault_lookup(ffff800020e5f978,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1448
uvm_fault(ffffffff8263e440,6b19aa5a3000,0,1) at uvm_fault+0x7f sys/uvm/uvm_fault.c:524
pageflttrap(ffff800020e5fb10,0) at pageflttrap+0x1b8 sys/arch/amd64/amd64/trap.c:221
kerntrap(ffff800020e5fb10) at kerntrap+0xec sys/arch/amd64/amd64/trap.c:302
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
pool_do_put(ffffffff826553e0,ffff800020efe000) at pool_do_put+0x12e sys/kern/subr_pool.c:836
pool_put(ffffffff826553e0,ffff800020efe000) at pool_put+0x6f sys/kern/subr_pool.c:794
pmap_destroy(fffffd807efff9f8) at pmap_destroy+0x248 sys/arch/amd64/amd64/pmap.c:1399
uvm_map_teardown(fffffd806e9488a8) at uvm_map_teardown+0x269 sys/uvm/uvm_map.c:2760
uvmspace_free(fffffd806e9488a8) at uvmspace_free+0x86 sys/uvm/uvm_map.c:3646
end trace frame: 0xffff800020e5fdd0, 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{1}>
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
acquiring blockable sleep lock with spinlock or critical section held (rwlock) vmmaplk
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff8220b555) at panic+0x15c sys/kern/subr_prf.c:207
witness_checkorder(ffffffff8263e458,1,0) at witness_checkorder+0x10e0 sys/kern/subr_witness.c:821
rw_enter_read(ffffffff8263e448) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:111
uvmfault_lookup(ffff800020e5f978,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1448
uvm_fault(ffffffff8263e440,6b19aa5a3000,0,1) at uvm_fault+0x7f sys/uvm/uvm_fault.c:524
pageflttrap(ffff800020e5fb10,0) at pageflttrap+0x1b8 sys/arch/amd64/amd64/trap.c:221
kerntrap(ffff800020e5fb10) at kerntrap+0xec sys/arch/amd64/amd64/trap.c:302
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
pool_do_put(ffffffff826553e0,ffff800020efe000) at pool_do_put+0x12e sys/kern/subr_pool.c:836
pool_put(ffffffff826553e0,ffff800020efe000) at pool_put+0x6f sys/kern/subr_pool.c:794
pmap_destroy(fffffd807efff9f8) at pmap_destroy+0x248 sys/arch/amd64/amd64/pmap.c:1399
uvm_map_teardown(fffffd806e9488a8) at uvm_map_teardown+0x269 sys/uvm/uvm_map.c:2760
uvmspace_free(fffffd806e9488a8) at uvmspace_free+0x86 sys/uvm/uvm_map.c:3646
uvm_exit(ffff800020ec87c8) at uvm_exit+0x29 sys/uvm/uvm_glue.c:297
reaper(ffff800020e19110) at reaper+0x189 sys/kern/kern_exit.c:456
end trace frame: 0x0, count: -16
ddb{1}> show registers
rdi 0
rsi 0x1
rbp 0xffff800020e5f5f0
rbx 0xffff800020e5f6a0
rdx 0xffff800020e19110
rcx 0
rax 0
r8 0xffffffff8199412f kprintf+0x16f
r9 0x1
r10 0x25
r11 0xe26ec0448a5e1f3a
r12 0x3000000008
r13 0xffff800020e5f600
r14 0x100
r15 0x1
rip 0xffffffff810c3ce8 db_enter+0x18
cs 0x8
rflags 0x246
rsp 0xffff800020e5f5e0
ss 0x10
db_enter+0x18: addq $0x8,%rsp
ddb{1}> show proc
PROC (reaper) pid=60436 stat=onproc
flags process=14000<NOZOMBIE,SYSTEM> proc=200<SYSTEM>
pri=4, usrpri=53, nice=20
forw=0xffffffffffffffff, list=0xffff800020e18ea0,0xffff800020e19600
process=0xffff800020e4c7b8 user=0xffff800020e5a000, vmspace=0xffffffff8263e440
estcpu=3, cpticks=11, pctcpu=0.2
user=0, sys=12, intr=0
ddb{1}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
43984 479628 0 0 3 0x14200 bored sosplice
15572 361989 87737 0 3 0x10008a pause ksh
87737 126117 87818 0 3 0x92 select sshd
57558 234646 1 0 3 0x100083 ttyin getty
87818 332619 1 0 3 0x80 select sshd
90891 377711 69305 74 3 0x100092 bpf pflogd
69305 73377 1 0 3 0x80 netio pflogd
73098 311520 36230 73 3 0x100090 kqread syslogd
36230 167117 1 0 3 0x100082 netio syslogd
25268 219509 1 77 3 0x100090 poll dhclient
67692 315408 1 0 3 0x80 poll dhclient
36021 387889 0 0 2 0x40014200 smr
61237 247074 0 0 3 0x14200 pgzero zerothread
57758 472440 0 0 3 0x14200 aiodoned aiodoned
28232 96609 0 0 3 0x14200 syncer update
34268 512122 0 0 3 0x14200 cleaner cleaner
* 3135 60436 0 0 7 0x14200 reaper
57018 269434 0 0 3 0x14200 pgdaemon pagedaemon
48528 240327 0 0 3 0x14200 bored crynlk
86793 359106 0 0 3 0x14200 bored crypto
58001 103997 0 0 3 0x40014200 acpi0 acpi0
10240 47925 0 0 3 0x40014200 idle1
71977 157013 0 0 3 0x14200 bored softnet
11814 311247 0 0 3 0x14200 bored systqmp
50838 20370 0 0 3 0x14200 bored systq
56963 372736 0 0 3 0x40014200 bored softclock
59373 305523 0 0 7 0x40014200 idle0
1 444187 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{1}> show all locks
CPU 1:
exclusive mutex pdppl r = 0 (0xffffffff826553f0)
#0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1 mtx_enter_try+0x102
#2 mtx_enter+0x4b sys/kern/kern_lock.c:266
#3 pool_put+0x64 sys/kern/subr_pool.c:792
#4 pmap_destroy+0x248 sys/arch/amd64/amd64/pmap.c:1399
#5 uvm_map_teardown+0x269 sys/uvm/uvm_map.c:2760
#6 uvmspace_free+0x86 sys/uvm/uvm_map.c:3646
#7 uvm_exit+0x29 sys/uvm/uvm_glue.c:297
#8 reaper+0x189 sys/kern/kern_exit.c:456
#9 proc_trampoline+0x1c
Process 3135 (reaper) thread 0xffff800020e19110 (60436)
exclusive kernel_lock &kernel_lock r = 1 (0xffffffff8265c968)
#0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1 uvm_map_teardown+0x261 sys/uvm/uvm_map.c:2759
#2 uvmspace_free+0x86 sys/uvm/uvm_map.c:3646
#3 uvm_exit+0x29 sys/uvm/uvm_glue.c:297
#4 reaper+0x189 sys/kern/kern_exit.c:456
#5 proc_trampoline+0x1c
exclusive mutex pdppl r = 0 (0xffffffff826553f0)
#0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1 mtx_enter_try+0x102
#2 mtx_enter+0x4b sys/kern/kern_lock.c:266
#3 pool_put+0x64 sys/kern/subr_pool.c:792
#4 pmap_destroy+0x248 sys/arch/amd64/amd64/pmap.c:1399
#5 uvm_map_teardown+0x269 sys/uvm/uvm_map.c:2760
#6 uvmspace_free+0x86 sys/uvm/uvm_map.c:3646
#7 uvm_exit+0x29 sys/uvm/uvm_glue.c:297
#8 reaper+0x189 sys/kern/kern_exit.c:456
#9 proc_trampoline+0x1c
ddb{1}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 9501 6417K 6924K 78643K 11271 0
pcb 13 8K 8K 78643K 82 0
rtable 87 3K 4K 78643K 321 0
ifaddr 58 11K 12K 78643K 96 0
counters 43 33K 34K 78643K 53 0
ioctlops 0 0K 4K 78643K 1476 0
iov 0 0K 12K 78643K 28 0
mount 1 1K 1K 78643K 1 0
vnodes 1239 78K 78K 78643K 1621 0
UFS quota 1 32K 32K 78643K 1 0
UFS mount 5 36K 36K 78643K 5 0
shm 2 1K 5K 78643K 3 0
VM map 2 1K 1K 78643K 2 0
sem 12 0K 1K 78643K 33 0
dirhash 12 2K 2K 78643K 12 0
ACPI 1809 196K 290K 78643K 12766 0
file desc 3 8K 25K 78643K 286 0
sigio 0 0K 0K 78643K 7 0
proc 59 63K 95K 78643K 598 0
subproc 22 1K 3K 78643K 238 0
NFS srvsock 1 0K 0K 78643K 1 0
NFS daemon 1 16K 16K 78643K 1 0
ip_moptions 0 0K 0K 78643K 23 0
in_multi 37 2K 2K 78643K 93 0
ether_multi 1 0K 0K 78643K 17 0
ISOFS mount 1 32K 32K 78643K 1 0
MSDOSFS mount 1 16K 16K 78643K 1 0
ttys 43 201K 201K 78643K 43 0
exec 0 0K 1K 78643K 266 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 71 35K 54K 78643K 1829 0
UVM aobj 4 2K 2K 78643K 6 0
memdesc 1 4K 4K 78643K 1 0
crypto data 1 1K 1K 78643K 1 0
ip6_options 0 0K 0K 78643K 58 0
NDP 10 0K 0K 78643K 21 0
temp 94 3038K 3102K 78643K 3467 0
kqueue 2 2K 8K 78643K 13 0
SYN cache 2 16K 16K 78643K 2 0
ddb{1}> show all pools
Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
arp 64 8 0 5 1 0 1 1 0 8 0
plcache 128 20 0 0 1 0 1 1 0 8 0
rtpcb 80 37 0 35 1 0 1 1 0 8 0
rtentry 112 60 0 28 2 1 1 2 0 8 0
unpcb 120 148 0 138 1 0 1 1 0 8 0
syncache 264 8 0 8 2 2 0 1 0 8 0
tcpqe 32 223 0 223 3 2 1 1 0 8 1
tcpcb 544 154 0 151 2 1 1 2 0 8 0
inpcb 280 385 0 379 2 1 1 2 0 8 0
nd6 48 9 0 6 1 0 1 1 0 8 0
ppxss 1128 2 0 2 1 1 0 1 0 8 0
pffrag 232 1 0 1 1 1 0 1 0 482 0
pffrnode 88 1 0 1 1 1 0 1 0 8 0
pffrent 40 45 0 45 1 1 0 1 0 8 0
pfosfp 40 846 0 423 5 0 5 5 0 8 0
pfosfpen 112 1428 0 714 21 0 21 21 0 8 0
pfstitem 24 34 0 29 1 0 1 1 0 8 0
pfstkey 112 34 0 29 1 0 1 1 0 8 0
pfstate 328 34 0 29 3 0 3 3 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 256 248 0 100 12 2 10 12 0 8 0
art_table 32 249 0 100 2 0 2 2 0 8 0
art_node 16 59 0 30 1 0 1 1 0 8 0
sysvmsgpl 40 4 0 4 1 1 0 1 0 8 0
semupl 112 1 0 1 1 1 0 1 0 8 0
semapl 112 27 0 17 1 0 1 1 0 8 0
shmpl 112 4 0 2 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1686 0 284 89 0 89 89 0 8 0
ffsino 272 1686 0 284 95 0 95 95 0 8 0
nchpl 144 2303 0 708 61 0 61 61 0 8 0
uvmvnodes 72 2095 0 0 39 0 39 39 0 8 0
vnodes 208 2095 0 0 111 0 111 111 0 8 0
namei 1024 6536 0 6536 2 1 1 1 0 8 1
percpumem 16 37 0 5 1 0 1 1 0 8 0
vcpupl 1984 2 0 0 1 0 1 1 0 8 0
vmpool 560 2 0 0 1 0 1 1 0 8 0
scxspl 192 6458 0 6458 12 11 1 7 0 8 1
plimitpl 152 45 0 37 1 0 1 1 0 8 0
sigapl 424 466 0 436 4 0 4 4 0 8 0
futexpl 56 3134 0 3134 2 2 0 1 0 8 0
knotepl 112 208 0 203 1 0 1 1 0 8 0
kqueuepl 144 28 0 27 1 0 1 1 0 8 0
pipelkpl 48 142 0 136 1 0 1 1 0 8 0
pipepl 120 284 0 275 1 0 1 1 0 8 0
fdescpl 496 450 0 436 3 0 3 3 0 8 0
filepl 152 2874 0 2796 5 0 5 5 0 8 0
lockfpl 104 43 0 42 1 0 1 1 0 8 0
lockfspl 48 19 0 18 1 0 1 1 0 8 0
sessionpl 112 30 0 19 1 0 1 1 0 8 0
pgrppl 48 36 0 25 1 0 1 1 0 8 0
ucredpl 96 177 0 168 1 0 1 1 0 8 0
zombiepl 144 438 0 435 1 0 1 1 0 8 0
processpl 984 466 0 435 5 0 5 5 0 8 0
procpl 624 883 0 852 4 0 4 4 0 8 0
srpgc 64 2 0 2 1 1 0 1 0 8 0
sosppl 128 5 0 5 1 1 0 1 0 8 0
sockpl 400 570 0 552 6 3 3 5 0 8 1
mcl64k 65536 7 0 0 1 0 1 1 0 8 0
mcl16k 16384 1 0 0 1 0 1 1 0 8 0
mcl12k 12288 3 0 0 1 0 1 1 0 8 0
mcl9k 9216 2 0 0 1 0 1 1 0 8 0
mcl8k 8192 3 0 0 1 0 1 1 0 8 0
mcl4k 4096 6 0 0 1 0 1 1 0 8 0
mcl2k 2048 190 0 0 23 0 23 23 0 8 0
mtagpl 80 43 0 0 1 0 1 1 0 8 0
mbufpl 256 488 0 0 30 0 30 30 0 8 0
bufpl 280 4409 0 191 302 0 302 302 0 8 0
anonpl 16 57810 0 56469 66 1 65 65 0 124 51
amapchunkpl 152 3182 0 3137 20 13 7 20 0 158 3
amappl16 192 1834 0 1818 44 0 44 44 0 8 35
amappl15 184 115 0 113 2 1 1 1 0 8 0
amappl14 176 26 0 23 1 0 1 1 0 8 0
amappl13 168 47 0 46 1 0 1 1 0 8 0
amappl12 160 142 0 138 1 0 1 1 0 8 0
amappl11 152 57 0 42 1 0 1 1 0 8 0
amappl10 144 21 0 19 1 0 1 1 0 8 0
amappl9 136 391 0 390 1 0 1 1 0 8 0
amappl8 128 442 0 440 2 0 2 2 0 8 1
amappl7 120 153 0 145 1 0 1 1 0 8 0
amappl6 112 33 0 33 2 1 1 1 0 8 1
amappl5 104 332 0 315 1 0 1 1 0 8 0
amappl4 96 542 0 517 1 0 1 1 0 8 0
amappl3 88 117 0 112 1 0 1 1 0 8 0
amappl2 80 2464 0 2397 3 1 2 3 0 8 0
amappl1 72 20016 0 19587 26 15 11 20 0 8 0
amappl 80 1225 0 1197 2 0 2 2 0 84 0
dma4096 4096 1 0 1 1 1 0 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 5 0 2 1 0 1 1 0 8 0
uaddrrnd 24 452 0 436 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 452 0 436 1 0 1 1 0 8 0
vmmpekpl 168 7834 0 7801 2 0 2 2 0 8 0
vmmpepl 168 71394 0 70409 162 36 126 126 0 357 70
vmsppl 368 451 0 435 2 0 2 2 0 8 0
pdppl 4096 912 0 872 6 0 6 6 0 8 0
pdppl: pool(0xffffffff826553e0:pdppl): page inconsistency: page 0xffff800020efa000; item ordinal 0; addr 0x6b19aa5a3888
pvpl 32 195136 0 191946 158 1 157 158 0 265 92
pmappl 232 451 0 435 2 0 2 2 0 8 0
extentpl 40 46 0 29 1 0 1 1 0 8 0
phpool 112 283 0 10 8 0 8 8 0 8 0


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[Anton Lindqvist]

#syz dup: panic: acquiring blockable sleep lock with spinlock or critical section held (kernel_lock) &kernel_lock (2)