panic: maddr rwlock 0xffff80000157f060: enter read deadlock Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *388481 13704 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83325ab2) at panic+0x1cf sys/kern/subr_prf.c:198 rw_do_enter_read(ffff80000157f060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806d45a900,ffffffff839adbf8,0,0,ffff80002a739a40,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159e400,83,0) at mld6_sendpkt+0x364 sys/netinet6/mld6.c:499 mld6_fasttimo() at mld6_fasttimo+0x16d mld6_checktimer sys/netinet6/mld6.c:395 [inline] mld6_fasttimo() at mld6_fasttimo+0x16d sys/netinet6/mld6.c:369 pffasttimo(ffffffff838bf828) at pffasttimo+0x184 sys/kern/uipc_domain.c:-1 timeout_run(ffffffff837b82a0,ffffffff838bf828) at timeout_run+0xf3 sys/kern/kern_timeout.c:-1 softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: 5 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: maddr rwlock 0xffff80000157f060: enter read deadlock ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83325ab2) at panic+0x1cf sys/kern/subr_prf.c:198 rw_do_enter_read(ffff80000157f060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806d45a900,ffffffff839adbf8,0,0,ffff80002a739a40,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159e400,83,0) at mld6_sendpkt+0x364 sys/netinet6/mld6.c:499 mld6_fasttimo() at mld6_fasttimo+0x16d mld6_checktimer sys/netinet6/mld6.c:395 [inline] mld6_fasttimo() at mld6_fasttimo+0x16d sys/netinet6/mld6.c:369 pffasttimo(ffffffff838bf828) at pffasttimo+0x184 sys/kern/uipc_domain.c:-1 timeout_run(ffffffff837b82a0,ffffffff838bf828) at timeout_run+0xf3 sys/kern/kern_timeout.c:-1 softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002a739750 rbx 0xffff80000157f000 rdx 0 rcx 0 rax 0xffff80002a72d4c0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x32fdbdb13c17f6aa r11 0xe5ce4e2b06aba8a7 r12 0 r13 0xffff80002a72d4c4 r14 0 r15 0x1 rip 0xffffffff82215455 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a739740 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=388481 pid=13704 tcnt=1 stat=onproc flags process=14000 proc=40000200 runpri=36, usrpri=50, slppri=36, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a72d758,0xffff80002a72d238 process=0xffff8000ffffe880 user=0xffff80002a734000, vmspace=0xffffffff839ad710 estcpu=0, cpticks=1, pctcpu=0.0, user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 42929 462250 49369 0 2 0 syz-executor 42929 344018 49369 0 3 0x4000080 fsleep syz-executor 4418 421332 55678 0 2 0 syz-executor 4418 201163 55678 0 2 0x4000000 syz-executor 4418 92856 55678 0 2 0x4000000 syz-executor 58085 440730 65683 0 3 0x80 nanoslp syz-executor 58085 308378 65683 0 2 0x4000000 syz-executor 58085 95808 65683 0 3 0x4000080 fsleep syz-executor 58085 201428 65683 0 3 0x4000080 fsleep syz-executor 42567 403486 81322 0 2 0 syz-executor 42567 117583 81322 0 2 0x4000000 syz-executor 42567 24185 81322 0 2 0x4000000 syz-executor 42567 346499 81322 0 3 0x4000080 fsleep syz-executor 39435 174304 79902 0 3 0x3000 suspend syz-executor 39435 315195 79902 0 2 0x4081000 syz-executor 39435 252345 79902 0 2 0x4081000 syz-executor 97766 454959 0 0 3 0x14280 nfsidl nfsio 77852 39817 0 0 3 0x14280 nfsidl nfsio 79974 388630 0 0 3 0x14280 nfsidl nfsio 237 406549 0 0 3 0x14280 nfsidl nfsio 12383 112135 0 0 3 0x14280 nfsidl nfsio 74400 109295 0 0 3 0x14280 nfsidl nfsio 60685 377373 0 0 3 0x14280 nfsidl nfsio 69903 167943 0 0 3 0x14280 nfsidl nfsio 69094 377237 0 0 3 0x14280 nfsidl nfsio 39584 89004 0 0 3 0x14280 nfsidl nfsio 90492 289211 0 0 3 0x14280 nfsidl nfsio 57138 46325 0 0 3 0x14280 nfsidl nfsio 20174 509810 0 0 3 0x14280 nfsidl nfsio 65925 92960 0 0 3 0x14280 nfsidl nfsio 28517 141551 0 0 3 0x14280 nfsidl nfsio 63877 38602 0 0 3 0x14280 nfsidl nfsio 7316 238024 0 0 3 0x14280 nfsidl nfsio 57341 405946 0 0 3 0x14280 nfsidl nfsio 70365 365329 0 0 3 0x14280 nfsidl nfsio 86883 278354 0 0 3 0x14280 nfsidl nfsio 55678 523133 98798 0 3 0x82 nanoslp syz-executor 65683 325514 98798 0 3 0x82 nanoslp syz-executor 49369 220053 98798 0 3 0x82 nanoslp syz-executor 79902 344870 98798 0 3 0x82 nanoslp syz-executor 81322 124193 98798 0 3 0x82 nanoslp syz-executor 98562 322356 98798 0 2 0x2 syz-executor 93540 361349 98798 0 3 0x82 wait syz-executor 8886 74338 98798 0 2 0x2 syz-executor 98798 86460 97802 0 3 0x82 kqread syz-executor 97802 254304 60432 0 3 0x10008a sigsusp ksh 60432 463543 50813 0 3 0x98 kqread sshd-session 50813 208795 33606 0 3 0x92 kqread sshd-session 2948 466477 1 0 3 0x100083 ttyopn getty 33606 493494 1 0 3 0x88 kqread sshd 76577 387524 99709 73 3 0x1100090 kqread syslogd 99709 350061 1 0 3 0x100082 sbwait syslogd 44982 194822 1 0 3 0x100080 kqread resolvd 99507 332761 56789 77 3 0x100092 kqread dhcpleased 35559 446453 56789 77 3 0x100092 kqread dhcpleased 56789 120615 1 0 3 0x80 kqread dhcpleased 40814 57955 0 0 3 0x14200 bored smr 45958 506839 0 0 2 0x14200 zerothread 60354 416806 0 0 3 0x14200 aiodoned aiodoned 43427 438078 0 0 3 0x14200 syncer update 50745 260865 0 0 3 0x14200 cleaner cleaner 47353 344499 0 0 3 0x14200 reaper reaper 4022 12826 0 0 3 0x14200 pgdaemon pagedaemon 70699 124541 0 0 3 0x14200 bored viomb 13856 420065 0 0 3 0x40014200 acpi0 acpi0 20813 302898 0 0 3 0x14200 bored softnet0 52387 486469 0 0 3 0x14200 bored systqmp 74796 284084 0 0 3 0x14200 bored systq *13704 388481 0 0 7 0x40014200 softclock 57604 97894 0 0 3 0x40014200 idle0 1 376858 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11033 12163K 12507K 166960K 12661 0 pcb 18 15K 17K 166960K 156 0 rtable 215 7K 8K 166960K 608 0 pf 29 12K 17K 166960K 72 0 ifaddr 38 6K 8K 166960K 59 0 ifgroup 46 2K 2K 166960K 82 0 sysctl 4 1K 9K 166960K 11 0 counters 32 17K 18K 166960K 111 0 ioctlops 0 0K 4K 166960K 147 0 iov 0 0K 12K 166960K 15 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1404 88K 89K 166960K 1736 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 9 0 VM map 2 1K 1K 166960K 2 0 sem 9 0K 0K 166960K 11 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 98K 166960K 394 0 sigio 1 0K 0K 166960K 8 0 proc 60 59K 100K 166960K 508 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 25 0 in_multi 88 6K 7K 166960K 110 0 ether_multi 1 0K 0K 166960K 1 0 mrt 0 0K 0K 166960K 1 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 383 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 228 150K 159K 166960K 5176 0 UVM aobj 15 4K 6K 166960K 18 0 pinsyscall 39 78K 94K 166960K 1465 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 13 0 NDP 10 0K 2K 166960K 36 0 temp 117 8666K 8730K 166960K 8722 0 kqueue 17 28K 29K 166960K 67 0 SYN cache 2 16K 16K 166960K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 55 0 52 1 0 1 1 0 8 0 rtentry 136 187 0 96 4 0 4 4 0 8 0 unpcb 144 193 0 166 1 0 1 1 0 8 0 syncache 336 3 0 3 1 1 0 1 0 8 0 tcpcb 736 106 0 99 4 0 4 4 0 8 3 arp 96 20 0 3 1 0 1 1 0 8 0 ipq 40 2 0 0 1 0 1 1 0 8 0 ipqe 40 2 0 0 1 0 1 1 0 8 0 inpcb 328 366 0 354 10 0 10 10 0 8 9 ip6q 72 1 0 0 1 0 1 1 0 8 0 ip6af 40 1 0 0 1 0 1 1 0 8 0 nd6 112 28 0 5 1 0 1 1 0 8 0 pkpcb 40 3 0 3 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1072 73 0 73 1 0 1 1 0 8 1 pppxif 1416 2 0 2 1 0 1 1 0 8 1 pfstscr 40 2 0 2 1 1 0 1 0 8 0 pfanchor 1288 2 0 0 1 0 1 1 0 8 0 pfstitem 24 2 0 0 1 0 1 1 0 8 0 pfstkey 128 3 0 1 1 0 1 1 0 8 0 pfstate 384 2 0 1 1 0 1 1 0 8 0 pfrule 1344 4 0 2 1 0 1 1 0 8 0 art_heap8 4096 3 0 0 3 0 3 3 0 8 0 art_heap4 256 507 0 131 31 1 30 31 0 8 3 art_table 40 510 0 131 5 0 5 5 0 8 0 art_node 32 122 0 40 1 0 1 1 0 8 0 sysvmsgpl 40 3 0 3 2 1 1 1 0 8 1 semapl 112 8 0 1 1 0 1 1 0 8 0 shmpl 112 13 0 2 1 0 1 1 0 8 0 dirhash 1024 19 0 2 3 0 3 3 0 8 0 dino2pl 256 2078 0 578 95 0 95 95 0 8 0 ffsino 256 2078 0 578 95 0 95 95 0 8 0 nchpl 144 2622 0 937 64 0 64 64 0 8 0 vnodes 216 2418 0 0 135 0 135 135 0 8 0 namei 1024 8153 0 8153 3 2 1 2 0 8 1 vcpupl 3904 1 0 0 1 0 1 1 0 8 0 vmpool 808 2 0 1 1 0 1 1 0 8 0 kstatmem 264 40 0 20 2 0 2 2 0 8 0 scsiplug 72 1 0 1 1 1 0 1 0 8 0 scxspl 216 8458 0 8458 2 1 1 2 1 8 1 plimitpl 152 67 0 51 1 0 1 1 0 8 0 sigapl 424 696 0 633 9 1 8 8 0 8 0 knotepl 120 13581 0 13473 17 8 9 10 0 8 5 kqueuepl 184 121 0 107 3 2 1 3 0 8 0 pipepl 304 128 0 101 3 0 3 3 0 8 0 fdescpl 448 663 0 633 5 1 4 5 0 8 0 filepl 120 3261 0 3026 12 1 11 11 0 8 1 lockfpl 104 90 0 88 1 0 1 1 0 8 0 lockfspl 48 39 0 37 1 0 1 1 0 8 0 sessionpl 144 21 0 13 1 0 1 1 0 8 0 pgrppl 48 29 0 13 1 0 1 1 0 8 0 ucredpl 104 516 0 504 1 0 1 1 0 8 0 zombiepl 144 707 0 705 1 0 1 1 0 8 0 processpl 1152 696 0 633 5 0 5 5 0 8 0 procpl 664 1102 0 1028 7 0 7 7 0 8 0 sosppl 176 1 0 1 1 1 0 1 0 8 0 sockpl 552 625 0 583 10 0 10 10 0 8 6 mcl64k 65536 14 0 14 2 1 1 1 0 8 1 mcl8k 8192 76 0 76 2 1 1 1 0 8 1 mcl4k 4096 2760 0 2703 13 5 8 13 0 8 0 mcl2k2 2112 1 0 1 1 1 0 1 0 8 0 mcl2k 2048 719 0 716 3 2 1 3 0 8 0 mtagpl 96 16 0 4 1 0 1 1 0 8 0 mbufpl 256 7000 0 6792 14 0 14 14 0 8 0 bufpl 280 2906 0 122 199 0 199 199 0 8 0 anonpl 24 117817 0 114735 43 11 32 36 0 187 6 amapchunkpl 152 15762 0 15290 34 6 28 28 0 158 7 amappl16 200 1824 0 1791 5 2 3 5 0 8 0 amappl15 192 8 0 8 1 1 0 1 0 8 0 amappl14 184 4 0 4 1 1 0 1 0 8 0 amappl13 176 408 0 406 1 0 1 1 0 8 0 amappl12 168 998 0 961 2 0 2 2 0 8 0 amappl11 160 8 0 8 1 1 0 1 0 8 0 amappl10 152 51 0 40 1 0 1 1 0 8 0 amappl9 144 277 0 277 1 1 0 1 0 8 0 amappl8 136 24 0 23 1 0 1 1 0 8 0 amappl7 128 78 0 77 1 0 1 1 0 8 0 amappl6 120 265 0 254 1 0 1 1 0 8 0 amappl5 112 70 0 62 1 0 1 1 0 8 0 amappl4 104 378 0 353 1 0 1 1 0 8 0 amappl3 96 2658 0 2572 3 0 3 3 0 8 0 amappl2 88 782 0 710 2 0 2 2 0 8 0 amappl1 80 9769 0 9244 13 1 12 13 0 8 0 amappl 88 4443 0 4284 5 0 5 5 0 92 0 uvmvnodes 80 99 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 7 0 7 1 1 0 1 0 8 0 dma128 128 254 0 254 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 17 0 3 1 0 1 1 0 8 0 uaddrrnd 24 663 0 633 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 662 0 633 1 0 1 1 0 8 0 vmmpekpl 168 6904 0 6873 2 0 2 2 0 8 0 vmmpepl 168 48470 0 46711 85 3 82 83 0 357 0 vmsppl 368 662 0 633 4 1 3 4 0 8 0 rwobjpl 40 15454 0 14501 11 0 11 11 0 8 0 pdppl 4096 1337 0 1269 100 32 68 83 0 8 0 pvpl 32 303402 0 295294 120 23 97 103 0 265 16 pmappl 216 664 0 634 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 382 0 49 11 0 11 11 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83325ab2) at panic+0x1cf sys/kern/subr_prf.c:198 rw_do_enter_read(ffff80000157f060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806d45a900,ffffffff839adbf8,0,0,ffff80002a739a40,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159e400,83,0) at mld6_sendpkt+0x364 sys/netinet6/mld6.c:499 mld6_fasttimo() at mld6_fasttimo+0x16d mld6_checktimer sys/netinet6/mld6.c:395 [inline] mld6_fasttimo() at mld6_fasttimo+0x16d sys/netinet6/mld6.c:369 pffasttimo(ffffffff838bf828) at pffasttimo+0x184 sys/kern/uipc_domain.c:-1 timeout_run(ffffffff837b82a0,ffffffff838bf828) at timeout_run+0xf3 sys/kern/kern_timeout.c:-1 softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83325ab2) at panic+0x1cf sys/kern/subr_prf.c:198 rw_do_enter_read(ffff80000157f060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806d45a9f0,ffff80000157f000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806d45a900,ffffffff839adbf8,0,0,ffff80002a739a40,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159e400,83,0) at mld6_sendpkt+0x364 sys/netinet6/mld6.c:499 mld6_fasttimo() at mld6_fasttimo+0x16d mld6_checktimer sys/netinet6/mld6.c:395 [inline] mld6_fasttimo() at mld6_fasttimo+0x16d sys/netinet6/mld6.c:369 pffasttimo(ffffffff838bf828) at pffasttimo+0x184 sys/kern/uipc_domain.c:-1 timeout_run(ffffffff837b82a0,ffffffff838bf828) at timeout_run+0xf3 sys/kern/kern_timeout.c:-1 softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d4c0) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10