panic: pool_p_free: rttmr free list modified: page 0xfffffd80622bd000; item addr 0xfffffd80622bdd48; offset 0x10=0x83930550 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 35977 31600 0 0x14000 0x200 1 systqmp 383532 37350 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833667b2) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_p_free(ffffffff83966250,fffffd80622bdf90) at pool_p_free+0x2d1 sys/kern/subr_pool.c:986 pool_gc_pages(0) at pool_gc_pages+0x357 sys/kern/subr_pool.c:1587 taskq_thread(ffffffff837c2430) at taskq_thread+0x157 sys/kern/kern_task.c:446 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: pool_p_free: rttmr free list modified: page 0xfffffd80622bd000; item addr 0xfffffd80622bdd48; offset 0x10=0x83930550 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833667b2) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_p_free(ffffffff83966250,fffffd80622bdf90) at pool_p_free+0x2d1 sys/kern/subr_pool.c:986 pool_gc_pages(0) at pool_gc_pages+0x357 sys/kern/subr_pool.c:1587 taskq_thread(ffffffff837c2430) at taskq_thread+0x157 sys/kern/kern_task.c:446 end trace frame: 0x0, count: -5 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80002a219f50 rbx 0xffff8000299eeddf rdx 0 rcx 0xffff8000ffffea60 rax 0xffff8000299edff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xc8d05f192ee9f7f9 r11 0xa5327da5b76a881b r12 0xffff8000299eebe0 r13 0 r14 0 r15 0x1 rip 0xffffffff814f2bd5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a219f40 ss 0 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (systqmp) tid=35977 pid=31600 tcnt=1 stat=onproc flags process=14000 proc=200 runpri=32, usrpri=51, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000ffffef90,0xffff8000ffffe540 process=0xffff8000ffff9380 user=0xffff80002a215000, vmspace=0xffffffff8398fd48 estcpu=1, cpticks=8, pctcpu=0.0, user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 80662 518818 56084 0 2 0 syz-executor 80662 129153 56084 0 2 0x4000000 syz-executor 87999 441702 68539 0 2 0 syz-executor 87999 258043 68539 0 2 0x4000000 syz-executor 67099 237671 44179 0 2 0 syz-executor 67099 39539 44179 0 3 0x4000080 ttyout syz-executor 67099 275233 44179 0 3 0x4000080 fsleep syz-executor 52468 197120 23989 0 2 0 syz-executor 52468 398856 23989 0 3 0x4000080 fsleep syz-executor 966 229717 31591 0 2 0 syz-executor 966 116463 31591 0 3 0x4000080 ttyin syz-executor 72282 324836 32317 0 2 0 syz-executor 31769 171704 19935 0 2 0 syz-executor 31769 436398 19935 0 3 0x4000080 fsleep syz-executor 31769 180072 19935 0 3 0x4000080 fsleep syz-executor 32317 347792 66952 0 2 0xc82 syz-executor 56084 104834 66952 0 2 0xc82 syz-executor 23989 151686 66952 0 2 0xc82 syz-executor 79034 164193 1 0 3 0x100083 ttyin getty 44179 382902 66952 0 2 0xc82 syz-executor 19935 281196 66952 0 2 0xc82 syz-executor 75473 511161 66952 0 2 0xc82 syz-executor 68539 113807 66952 0 2 0xc82 syz-executor 31591 254022 66952 0 2 0xc82 syz-executor 88223 171333 0 0 3 0x14200 bored sosplice 66952 239521 80954 0 2 0xc82 syz-executor 80954 433801 60364 0 3 0x10008a sigsusp ksh 60364 238164 21100 0 3 0x98 kqread sshd-session 21100 89533 83899 0 3 0x92 kqread sshd-session 83899 238950 1 0 3 0x88 kqread sshd 37055 509960 58355 74 3 0x1100092 bpf pflogd 58355 458256 1 0 3 0x80 sbwait pflogd 13960 505176 53971 73 3 0x1100090 kqread syslogd 53971 227098 1 0 3 0x100082 sbwait syslogd 12299 104813 1 0 3 0x100080 kqread resolvd 27519 324533 76196 77 3 0x100092 kqread dhcpleased 61671 398785 76196 77 3 0x100092 kqread dhcpleased 76196 58659 1 0 3 0x80 kqread dhcpleased 71717 160293 0 0 3 0x14200 bored smr 39266 26133 0 0 2 0x14200 zerothread 33217 156196 0 0 3 0x14200 aiodoned aiodoned 68026 394212 0 0 2 0x14e00 update 30889 276395 0 0 3 0x14200 cleaner cleaner 62272 398599 0 0 3 0x14200 reaper reaper 46712 469779 0 0 3 0x14200 pgdaemon pagedaemon 5192 268523 0 0 3 0x14200 bored viomb 64698 235701 0 0 3 0x40014200 acpi0 acpi0 42752 125744 0 0 3 0x40014200 idle1 3498 345308 0 0 3 0x14200 bored softnet7 29450 86033 0 0 3 0x14200 bored softnet6 50778 330627 0 0 3 0x14200 bored softnet5 42385 323745 0 0 3 0x14200 bored softnet4 46217 442358 0 0 3 0x14200 bored softnet3 90879 40479 0 0 3 0x14200 bored softnet2 60476 198618 0 0 3 0x14200 bored softnet1 85938 385571 0 0 2 0x14200 softnet0 *31600 35977 0 0 7 0x14200 systqmp 29563 421063 0 0 3 0x14200 bored systq 39681 397668 0 0 2 0x14200 softclockmp 37350 383532 0 0 7 0x40014200 softclock 14034 222787 0 0 3 0x40014200 idle0 1 433121 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks CPU 0: exclusive mutex /syzkaller/managers/multicore/kernel/sys/kern/kern_timeout.c:62 r = 0 (0xffffffff837a96e0) #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_try+0x1ad sys/kern/kern_lock.c:311 #2 mtx_enter+0x62 sys/kern/kern_lock.c:261 #3 timeout_run+0x178 sys/kern/kern_timeout.c:702 #4 softclock_process_tick_timeout+0x232 sys/kern/kern_timeout.c:756 #5 softclock+0x152 sys/kern/kern_timeout.c:788 #6 softintr_dispatch+0x13b sys/kern/kern_softintr.c:84 #7 dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 #8 Xsoftclock+0x27 Process 80662 (syz-executor) thread 0xffff80003c45aa88 (518818) Process 80662 (syz-executor) thread 0xffff80003c45b780 (129153) Process 87999 (syz-executor) thread 0xffff80003c45bcb0 (258043) Process 31600 (systqmp) thread 0xffff8000ffffea60 (35977) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10271 11140K 12564K 166960K 21779 0 pcb 20 20K 30K 166960K 2177 0 rtable 222 15K 16K 166960K 1406 0 pf 42 18K 21K 166960K 554 0 ifaddr 46 9K 9K 166960K 414 0 ifgroup 69 2K 3K 166960K 698 0 sysctl 4 1K 9K 166960K 56 0 counters 80 38K 38K 166960K 1034 0 ioctlops 0 0K 6K 166960K 3319 0 iov 0 0K 32K 166960K 534 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1550 97K 98K 166960K 7336 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 120K 120K 166960K 66 0 VM map 2 1K 1K 166960K 2 0 sem 29 20K 21K 166960K 171 0 dirhash 12 2K 2K 166960K 96 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 240K 166960K 7111 0 sigio 0 0K 0K 166960K 277 0 proc 72 115K 180K 166960K 1942 0 subproc 72 4K 4K 166960K 264 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 1030 0 in_multi 73 5K 7K 166960K 623 0 ether_multi 1 0K 0K 166960K 62 0 mrt 2 0K 0K 166960K 52 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 265 1182K 1182K 166960K 265 0 exec 0 0K 1K 166960K 2114 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 15 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 253 177K 195K 166960K 63347 0 UVM aobj 61 6K 6K 166960K 72 0 pinsyscall 42 84K 102K 166960K 8822 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 472 0 NDP 16 0K 2K 166960K 302 0 temp 88 8652K 8780K 166960K 408462 0 kqueue 14 22K 34K 166960K 1365 0 SYN cache 2 8K 16K 166960K 3 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 26 0 0 1 0 1 1 0 8 0 rtpcb 120 943 0 940 12 11 1 3 0 8 0 rtentry 176 492 0 419 6 2 4 5 0 8 0 unpcb 144 5790 0 5771 45 44 1 7 0 8 0 syncache 336 29 0 29 12 12 0 1 0 8 0 tcpqe 32 12 0 12 9 9 0 1 0 8 0 tcpcb 736 2657 0 2651 54 53 1 10 0 8 0 arp 128 59 0 44 1 0 1 1 0 8 0 inpcb 328 9275 0 9264 109 103 6 15 0 8 4 nd6 144 97 0 85 1 0 1 1 0 8 0 pkpcb 40 140 0 140 19 18 1 1 0 8 1 kcovpl 48 29 0 21 1 0 1 1 0 8 0 mppekey 1024 9 0 9 5 5 0 1 0 8 0 ppxss 1192 409 0 406 11 10 1 1 0 8 0 pppxif 1504 90 0 90 17 17 0 1 0 8 0 pffrag 232 130 0 119 1 0 1 1 0 482 0 pffrnode 88 120 0 110 1 0 1 1 0 8 0 pffrent 40 300 0 288 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 pfrktable 1344 1 0 1 1 1 0 1 0 8 0 pfstitem 24 529 0 432 1 0 1 1 0 8 0 pfstkey 128 529 0 432 5 1 4 5 0 8 0 pfstate 384 529 0 432 15 4 11 13 0 8 0 pfrule 1344 23 0 18 2 1 1 2 0 8 0 rttmr 136 10 0 10 7 7 0 1 0 8 0 art_heap8 4096 7 0 3 7 3 4 5 0 8 0 art_heap4 256 2627 0 2304 67 44 23 29 0 8 0 art_table 40 2634 0 2307 5 1 4 5 0 8 0 art_node 32 491 0 432 1 0 1 1 0 8 0 sysvmsgpl 40 22 0 15 1 0 1 1 0 8 0 semupl 112 4 0 4 3 3 0 1 0 8 0 semapl 112 157 0 130 1 0 1 1 0 8 0 shmpl 112 69 0 11 2 0 2 2 0 8 0 dirhash 1024 75 0 58 3 0 3 3 0 8 0 dino2pl 256 14902 0 13349 98 0 98 98 0 8 0 ffsino 296 14902 0 13349 121 1 120 121 0 8 0 nchpl 144 25188 0 24600 64 38 26 64 0 8 0 rtmask 32 60 0 60 19 18 1 1 0 8 1 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 90340 0 90340 10 9 1 2 0 8 1 percpumem 16 532 0 477 1 0 1 1 0 8 0 kstatmem 264 486 0 448 3 0 3 3 0 8 0 acpiwqpl 32 4 0 4 1 0 1 1 1 8 1 scsiplug 72 39 0 39 16 16 0 1 0 8 0 scxspl 216 182623 0 182623 26 25 1 8 1 8 1 plimitpl 152 1846 0 1828 1 0 1 1 0 8 0 sigapl 424 7394 0 7339 9 1 8 9 0 8 0 knotepl 120 935 0 0 25 0 25 25 0 8 0 kqueuepl 224 2607 0 2596 29 27 2 5 0 8 1 pipepl 344 886 0 858 12 9 3 9 0 8 0 fdescpl 528 7327 0 7296 3 0 3 3 0 8 0 filepl 160 55993 0 55770 69 55 14 20 0 8 0 lockfpl 104 3452 0 3450 5 4 1 2 0 8 0 lockfspl 48 1387 0 1385 1 0 1 1 0 8 0 sessionpl 144 73 0 64 1 0 1 1 0 8 0 pgrppl 48 241 0 224 1 0 1 1 0 8 0 ucredpl 104 9359 0 9346 1 0 1 1 0 8 0 zombiepl 144 9493 0 9492 2 1 1 1 0 8 0 processpl 1248 7394 0 7339 7 1 6 7 0 8 0 procpl 664 18729 0 18666 8 1 7 8 0 8 0 sosppl 168 58 0 58 16 15 1 1 0 8 1 sockpl 752 16436 0 16402 186 176 10 29 0 8 6 mcl64k 65536 19 0 0 3 0 3 3 0 8 0 mcl16k 16384 3 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 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 135 0 0 15 0 15 15 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 73 0 0 6 0 6 6 0 8 0 mtagpl 96 220 0 0 6 0 6 6 0 8 0 mbufpl 256 1447 0 0 82 0 82 82 0 8 0 bufpl 280 74078 0 67935 440 0 440 440 0 8 0 anonpl 32 20764 0 0 166 0 166 166 0 246 0 amapchunkpl 152 231988 0 231307 134 102 32 37 0 158 3 amappl16 200 27156 0 26830 220 189 31 46 0 8 2 amappl15 192 3 0 3 1 1 0 1 0 8 0 amappl14 184 207 0 194 1 0 1 1 0 8 0 amappl13 176 8 0 8 4 4 0 1 0 8 0 amappl12 168 8339 0 8307 3 1 2 2 0 8 0 amappl11 160 49 0 35 1 0 1 1 0 8 0 amappl10 152 17 0 16 2 1 1 1 0 8 0 amappl9 144 254 0 253 2 1 1 1 0 8 0 amappl8 136 28 0 25 1 0 1 1 0 8 0 amappl7 128 175 0 162 1 0 1 1 0 8 0 amappl6 120 416 0 411 1 0 1 1 0 8 0 amappl5 112 222 0 212 1 0 1 1 0 8 0 amappl4 104 418 0 396 1 0 1 1 0 8 0 amappl3 96 47830 0 47713 4 0 4 4 0 8 0 amappl2 88 1182 0 1115 2 0 2 2 0 8 0 amappl1 80 43642 0 43037 18 2 16 17 0 8 0 amappl 88 61055 0 60876 5 0 5 5 0 92 0 dma65536 65536 2 0 2 2 2 0 2 0 8 0 dma32768 32768 1 0 1 1 1 0 1 0 8 0 dma16384 16384 1 0 1 1 1 0 1 0 8 0 dma8192 8192 1 0 1 1 1 0 1 0 8 0 dma4096 4096 2 0 2 2 2 0 1 0 8 0 dma2048 2048 1 0 1 1 1 0 1 0 8 0 dma1024 1024 3 0 2 1 0 1 1 0 8 0 dma256 256 12 0 12 6 6 0 1 0 8 0 dma128 128 270 0 270 13 13 0 1 0 8 0 dma64 64 10 0 10 5 5 0 1 0 8 0 dma32 32 8 0 8 2 2 0 1 0 8 0 dma16 16 23 0 22 1 0 1 1 0 8 0 aobjpl 72 71 0 11 2 0 2 2 0 8 0 uaddrrnd 24 7327 0 7295 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 7327 0 7295 1 0 1 1 0 8 0 vmmpekpl 168 53554 0 53487 4 0 4 4 0 8 0 vmmpepl 168 469974 0 467529 230 104 126 134 0 357 4 vmsppl 488 7326 0 7295 5 0 5 5 0 8 0 rwobjpl 80 122470 0 115230 186 30 156 160 0 8 0 pdppl 4096 14661 0 14590 213 142 71 85 0 8 0 pvpl 32 29422 0 0 237 2 235 236 0 265 0 pmappl 256 7326 0 7295 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 595 0 282 10 0 10 10 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8383fff0) 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(ffffffff8394d108) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8394d108) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8394d108) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8394d108) at __mp_lock+0x192 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff8394d108,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 softclock_thread_run(ffffffff837a9778) at softclock_thread_run+0x79 sys/kern/kern_timeout.c:836 softclock_thread(ffff8000fffff4c0) at softclock_thread+0x10a sys/kern/kern_timeout.c:858 end trace frame: 0x0, count: 3 ddb{0}> trace x86_ipi_db(ffffffff8383fff0) 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(ffffffff8394d108) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8394d108) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8394d108) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8394d108) at __mp_lock+0x192 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff8394d108,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 softclock_thread_run(ffffffff837a9778) at softclock_thread_run+0x79 sys/kern/kern_timeout.c:836 softclock_thread(ffff8000fffff4c0) at softclock_thread+0x10a sys/kern/kern_timeout.c:858 end trace frame: 0x0, count: -12 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x25: addq $0x8,%rsp db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833667b2) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_p_free(ffffffff83966250,fffffd80622bdf90) at pool_p_free+0x2d1 sys/kern/subr_pool.c:986 pool_gc_pages(0) at pool_gc_pages+0x357 sys/kern/subr_pool.c:1587 taskq_thread(ffffffff837c2430) at taskq_thread+0x157 sys/kern/kern_task.c:446 end trace frame: 0x0, count: 10 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833667b2) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_p_free(ffffffff83966250,fffffd80622bdf90) at pool_p_free+0x2d1 sys/kern/subr_pool.c:986 pool_gc_pages(0) at pool_gc_pages+0x357 sys/kern/subr_pool.c:1587 taskq_thread(ffffffff837c2430) at taskq_thread+0x157 sys/kern/kern_task.c:446 end trace frame: 0x0, count: -5