panic: pool_p_free: pffrnode free list modified: page 0xfffffd8065b7c000; item addr 0xfffffd8065b7c000; offset 0x0=0x0 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 297264 27104 73 0x100010 0 1K syslogd *166948 23510 0 0x14000 0x200 0 systqmp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8224c780) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff826891c0,fffffd8065b7cf90) at pool_p_free+0x1de sys/kern/subr_pool.c:983 pool_gc_pages(0) at pool_gc_pages+0x255 sys/kern/subr_pool.c:1578 taskq_thread(ffffffff8252a940) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: 10 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 pool_p_free: pffrnode free list modified: page 0xfffffd8065b7c000; item addr 0xfffffd8065b7c000; offset 0x0=0x0 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8224c780) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff826891c0,fffffd8065b7cf90) at pool_p_free+0x1de sys/kern/subr_pool.c:983 pool_gc_pages(0) at pool_gc_pages+0x255 sys/kern/subr_pool.c:1578 taskq_thread(ffffffff8252a940) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: -5 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800020a33a00 rbx 0xffff800020a33ab0 rdx 0xffff800020a18270 rcx 0 rax 0 r8 0xffffffff81e0c6df kprintf+0x16f r9 0x1 r10 0x25 r11 0xd0cf18a6a7bbea26 r12 0x3000000008 r13 0xffff800020a33a10 r14 0x100 r15 0x1 rip 0xffffffff812eee78 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a339f0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (systqmp) pid=166948 stat=onproc flags process=14000 proc=200 pri=32, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a184e0,0xffff800020a18010 process=0xffff800020a1a3c0 user=0xffff800020a2e000, vmspace=0xffffffff82650700 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 35754 432637 81578 0 3 0x80 nanosleep syz-executor.0 35754 499673 81578 0 3 0x4000080 select syz-executor.0 41840 440344 0 0 3 0x14200 bored sosplice 63375 439689 41952 0 3 0x82 piperd syz-executor.1 81578 516678 41952 0 3 0x82 nanosleep syz-executor.0 41952 423728 63362 0 3 0x82 thrsleep syz-fuzzer 41952 460902 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 101894 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 77222 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 353762 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 121118 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 418154 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 346638 63362 0 3 0x4000082 kqread syz-fuzzer 41952 149653 63362 0 3 0x4000082 thrsleep syz-fuzzer 41952 417540 63362 0 3 0x4000082 thrsleep syz-fuzzer 63362 97009 96355 0 3 0x10008a pause ksh 96355 368299 68422 0 3 0x92 select sshd 60800 56446 1 0 3 0x100083 ttyin getty 68422 68480 1 0 3 0x80 select sshd 8578 169174 78480 74 2 0x100012 pflogd 78480 13976 1 0 3 0x80 netio pflogd 27104 297264 40354 73 7 0x100010 syslogd 40354 346094 1 0 3 0x100082 netio syslogd 68934 294425 1 77 3 0x100090 poll dhclient 47958 434894 1 0 3 0x80 poll dhclient 72778 428765 0 0 3 0x14200 bored smr 49541 515895 0 0 3 0x14200 pgzero zerothread 30253 458476 0 0 3 0x14200 aiodoned aiodoned 30539 256927 0 0 3 0x14200 syncer update 77280 438942 0 0 3 0x14200 cleaner cleaner 78466 120777 0 0 3 0x14200 reaper reaper 50690 509738 0 0 3 0x14200 pgdaemon pagedaemon 89279 436932 0 0 3 0x14200 bored crynlk 85524 161519 0 0 3 0x14200 bored crypto 28208 453056 0 0 3 0x40014200 acpi0 acpi0 65207 59386 0 0 3 0x40014200 idle1 7241 123436 0 0 3 0x14200 bored softnet *23510 166948 0 0 7 0x14200 systqmp 73352 4539 0 0 3 0x14200 bored systq 85336 218542 0 0 3 0x40014200 bored softclock 20889 371439 0 0 3 0x40014200 idle0 1 510878 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 23510 (systqmp) thread 0xffff800020a18270 (166948) shared rwlock pools r = 0 (0xffffffff825296b0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 pool_gc_pages+0x21 sys/kern/subr_pool.c:1555 #2 taskq_thread+0x9c sys/kern/kern_task.c:369 #3 proc_trampoline+0x1c shared rwlock systqmp r = 0 (0xffffffff8252a9a0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 taskq_thread+0x8f sys/kern/kern_task.c:368 #2 proc_trampoline+0x1c ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9500 6413K 6793K 78643K 10819 0 pcb 13 8K 8K 78643K 85 0 rtable 113 4K 4K 78643K 281 0 ifaddr 59 12K 14K 78643K 104 0 counters 43 33K 34K 78643K 61 0 ioctlops 0 0K 4K 78643K 1477 0 iov 0 0K 12K 78643K 16 0 mount 1 1K 1K 78643K 1 0 vnodes 1222 77K 77K 78643K 1296 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 6 0 VM map 2 1K 1K 78643K 2 0 sem 12 1K 1K 78643K 18 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 111 0 sigio 0 0K 0K 78643K 5 0 proc 63 63K 95K 78643K 450 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 9 0 in_multi 40 2K 2K 78643K 45 0 ether_multi 1 0K 0K 78643K 3 0 mrt 0 0K 0K 78643K 3 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 55 254K 254K 78643K 55 0 exec 0 0K 1K 78643K 211 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 115 54K 54K 78643K 1278 0 UVM aobj 13 2K 2K 78643K 29 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 17 0 NDP 9 0K 0K 78643K 22 0 temp 102 3021K 3086K 78643K 4762 0 kqueue 3 4K 12K 78643K 12 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 arp 64 6 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 31 0 29 1 0 1 1 0 8 0 rtentry 112 47 0 2 2 0 2 2 0 8 0 unpcb 120 85 0 75 1 0 1 1 0 8 0 syncache 264 5 0 5 2 1 1 1 0 8 1 tcpqe 32 98 0 98 1 1 0 1 0 8 0 tcpcb 544 33 0 29 1 0 1 1 0 8 0 inpcb 280 170 0 162 2 0 2 2 0 8 1 rttmr 72 1 0 1 1 0 1 1 0 8 1 nd6 48 7 0 0 1 0 1 1 0 8 0 ppxss 1128 1 0 1 1 0 1 1 0 8 1 pffrag 232 3 0 3 1 1 0 1 0 482 0 pffrnode 88 3 0 3 1 1 0 1 0 8 0 pffrent 40 135 0 135 1 0 1 1 0 8 1 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 25 0 0 1 0 1 1 0 8 0 pfstkey 112 25 0 0 1 0 1 1 0 8 0 pfstate 328 25 0 0 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 256 191 0 0 12 0 12 12 0 8 0 art_table 32 192 0 0 2 0 2 2 0 8 0 art_node 16 46 0 5 1 0 1 1 0 8 0 sysvmsgpl 40 11 0 2 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 16 0 6 1 0 1 1 0 8 0 shmpl 112 27 0 16 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1562 0 155 46 0 46 46 0 8 0 ffsino 272 1562 0 155 95 0 95 95 0 8 0 nchpl 144 1899 0 284 61 0 61 61 0 8 0 uvmvnodes 72 1652 0 0 31 0 31 31 0 8 0 vnodes 208 1652 0 0 87 0 87 87 0 8 0 namei 1024 5064 0 5064 1 0 1 1 0 8 1 percpumem 16 41 0 9 1 0 1 1 0 8 0 vcpupl 1984 4 0 0 1 0 1 1 0 8 0 vmpool 560 4 0 0 1 0 1 1 0 8 0 scxspl 192 5650 0 5648 8 1 7 7 0 8 6 plimitpl 152 17 0 9 1 0 1 1 0 8 0 sigapl 424 327 0 295 4 0 4 4 0 8 0 futexpl 56 1663 0 1663 1 0 1 1 0 8 1 knotepl 112 65 0 46 1 0 1 1 0 8 0 kqueuepl 144 20 0 18 1 0 1 1 0 8 0 pipelkpl 48 96 0 86 1 0 1 1 0 8 0 pipepl 120 192 0 173 1 0 1 1 0 8 0 fdescpl 496 311 0 295 3 0 3 3 0 8 0 filepl 152 1817 0 1717 5 0 5 5 0 8 1 lockfpl 104 36 0 35 1 0 1 1 0 8 0 lockfspl 48 15 0 14 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 22 0 11 1 0 1 1 0 8 0 ucredpl 96 141 0 132 1 0 1 1 0 8 0 zombiepl 144 295 0 295 1 0 1 1 0 8 1 processpl 960 327 0 295 5 0 5 5 0 8 0 procpl 624 513 0 471 4 0 4 4 0 8 0 sosppl 128 2 0 2 1 0 1 1 0 8 1 sockpl 400 287 0 268 3 0 3 3 0 8 1 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 3 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 151 0 0 18 0 18 18 0 8 0 mtagpl 80 4 0 0 1 0 1 1 0 8 0 mbufpl 256 247 0 0 15 0 15 15 0 8 0 bufpl 280 4255 0 175 292 0 292 292 0 8 0 anonpl 16 44610 0 27637 70 1 69 69 0 124 0 amapchunkpl 152 1485 0 1342 8 1 7 8 0 158 0 amappl16 192 1377 0 454 47 0 47 47 0 8 0 amappl15 184 3 0 2 2 1 1 1 0 8 0 amappl14 176 5 0 3 2 1 1 1 0 8 0 amappl13 168 25 0 24 1 0 1 1 0 8 0 amappl12 160 17 0 13 2 1 1 1 0 8 0 amappl11 152 156 0 135 1 0 1 1 0 8 0 amappl10 144 17 0 13 1 0 1 1 0 8 0 amappl9 136 390 0 387 1 0 1 1 0 8 0 amappl8 128 317 0 295 1 0 1 1 0 8 0 amappl7 120 117 0 106 1 0 1 1 0 8 0 amappl6 112 101 0 95 1 0 1 1 0 8 0 amappl5 104 173 0 159 1 0 1 1 0 8 0 amappl4 96 535 0 502 2 1 1 2 0 8 0 amappl3 88 111 0 104 1 0 1 1 0 8 0 amappl2 80 1580 0 1506 3 1 2 3 0 8 0 amappl1 72 16799 0 16361 25 15 10 20 0 8 0 amappl 80 764 0 714 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 28 0 16 1 0 1 1 0 8 0 uaddrrnd 24 315 0 295 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 315 0 295 1 0 1 1 0 8 0 vmmpekpl 168 6297 0 6262 2 0 2 2 0 8 0 vmmpepl 168 45230 0 43160 123 7 116 118 0 357 22 vmsppl 368 314 0 295 2 0 2 2 0 8 0 pdppl 4096 638 0 594 6 0 6 6 0 8 0 pvpl 32 152863 0 132774 166 0 166 166 0 265 2 pmappl 232 314 0 295 2 0 2 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 168 0 3 5 0 5 5 0 8 0