panic: maddr rwlock 0xffff800001565860: enter read deadlock Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 98501 89022 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(ffff800001565860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806bb52200,ffffffff839adbf8,0,0,ffff80002a739540,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001597980,83,0) 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(ffff80002a72cf90) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72cf90) 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 0xffff800001565860: 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(ffff800001565860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806bb52200,ffffffff839adbf8,0,0,ffff80002a739540,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001597980,83,0) 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(ffff80002a72cf90) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72cf90) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002a739250 rbx 0xffff800001565800 rdx 0 rcx 0 rax 0xffff80002a72cf90 r8 0x101010101010101 r9 0x8080808080808080 r10 0xe7469b38c53b2e03 r11 0xbc44322245a76744 r12 0 r13 0xffff80002a72cf94 r14 0 r15 0x1 rip 0xffffffff82215455 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a739240 ss 0 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=98501 pid=89022 tcnt=1 stat=onproc flags process=14000 proc=40000200 runpri=0, usrpri=50, slppri=0, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a72d228,0xffff80002a72cd08 process=0xffff8000ffffd200 user=0xffff80002a734000, vmspace=0xffffffff839ad710 estcpu=0, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 512 36770 9889 0 2 0 syz-executor 512 452816 9889 0 3 0x4000080 lockf syz-executor 75488 270653 59382 0 2 0 syz-executor 75488 369914 59382 0 3 0x4000000 smrbar syz-executor 61920 108740 4445 0 2 0 syz-executor 61920 458699 4445 0 3 0x4000080 dtread syz-executor 86513 328022 88359 0 2 0 syz-executor 86513 455453 88359 0 3 0x4000080 fsleep syz-executor 86513 26941 88359 0 3 0x4000080 fsleep syz-executor 9889 192838 88764 0 2 0xc82 syz-executor 52455 474983 0 0 3 0x14280 nfsidl nfsio 6411 182554 0 0 3 0x14280 nfsidl nfsio 20365 198870 0 0 3 0x14280 nfsidl nfsio 32464 95012 0 0 3 0x14280 nfsidl nfsio 23030 155117 0 0 3 0x14280 nfsidl nfsio 75347 281307 0 0 3 0x14280 nfsidl nfsio 27920 271021 0 0 3 0x14280 nfsidl nfsio 3201 269060 0 0 3 0x14280 nfsidl nfsio 18278 447720 0 0 3 0x14280 nfsidl nfsio 77175 467199 0 0 3 0x14280 nfsidl nfsio 34442 302986 0 0 3 0x14280 nfsidl nfsio 93395 414921 0 0 3 0x14280 nfsidl nfsio 49186 153086 0 0 3 0x14280 nfsidl nfsio 40129 230297 0 0 3 0x14280 nfsidl nfsio 41624 312484 0 0 3 0x14280 nfsidl nfsio 8746 292031 0 0 3 0x14280 nfsidl nfsio 86886 18839 0 0 3 0x14280 nfsidl nfsio 13956 331851 0 0 3 0x14280 nfsidl nfsio 46930 414759 0 0 3 0x14280 nfsidl nfsio 48021 93309 0 0 3 0x14280 nfsidl nfsio 38531 11203 0 0 3 0x14200 acct acct 81578 178815 88764 0 3 0x82 nanoslp syz-executor 72519 134597 88764 0 3 0x82 wait syz-executor 88359 322028 88764 0 3 0x82 nanoslp syz-executor 59382 80818 88764 0 2 0xc82 syz-executor 4445 36815 88764 0 2 0xc82 syz-executor 90059 297114 88764 0 2 0xc82 syz-executor 66701 316324 88764 0 2 0xc82 syz-executor 88764 176142 68859 0 3 0x82 kqread syz-executor 68859 452987 11151 0 3 0x10008a sigsusp ksh 11151 406740 15237 0 3 0x98 kqread sshd-session 15237 186522 60252 0 3 0x92 kqread sshd-session 15140 57197 1 0 3 0x100083 ttyin getty 60252 339675 1 0 3 0x88 kqread sshd 25747 239924 64607 73 3 0x1100090 kqread syslogd 64607 299662 1 0 3 0x100082 sbwait syslogd 75721 493851 1 0 3 0x100080 kqread resolvd 62505 291365 15342 77 3 0x100092 kqread dhcpleased 17499 371813 15342 77 3 0x100092 kqread dhcpleased 15342 341450 1 0 3 0x80 kqread dhcpleased 42063 81353 0 0 2 0x14200 smr 46170 159432 0 0 2 0x14200 zerothread 26121 179594 0 0 3 0x14200 aiodoned aiodoned 81923 402732 0 0 3 0x14200 syncer update 51994 180061 0 0 3 0x14200 cleaner cleaner 71480 392473 0 0 3 0x14200 reaper reaper 74588 394375 0 0 3 0x14200 pgdaemon pagedaemon 27776 117877 0 0 3 0x14200 bored viomb 92075 309119 0 0 3 0x40014200 acpi0 acpi0 10564 140151 0 0 3 0x14200 bored softnet0 54719 107098 0 0 3 0x14200 smrbar systqmp 11501 427420 0 0 3 0x14200 bored systq *89022 98501 0 0 7 0x40014200 softclock 73039 398022 0 0 3 0x40014200 idle0 1 154187 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 11057 12172K 13234K 166960K 13320 0 pcb 18 13K 14K 166960K 143 0 rtable 206 6K 7K 166960K 438 0 pf 34 13K 15K 166960K 57 0 ifaddr 40 6K 7K 166960K 62 0 ifgroup 50 2K 2K 166960K 77 0 sysctl 3 1K 9K 166960K 7 0 counters 35 18K 18K 166960K 45 0 ioctlops 0 0K 4K 166960K 92 0 iov 0 0K 20K 166960K 23 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1458 92K 92K 166960K 1833 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 13 0 VM map 2 1K 1K 166960K 2 0 sem 8 1K 1K 166960K 9 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 97K 166960K 514 0 sigio 0 0K 0K 166960K 8 0 proc 60 59K 91K 166960K 535 0 subproc 72 4K 4K 166960K 81 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 3 0K 0K 166960K 45 0 in_multi 88 6K 7K 166960K 126 0 ether_multi 2 0K 0K 166960K 3 0 mrt 1 0K 0K 166960K 4 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 79 360K 360K 166960K 79 0 exec 0 0K 1K 166960K 432 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 2 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 233 143K 159K 166960K 6141 0 UVM aobj 15 4K 4K 166960K 17 0 pinsyscall 39 78K 96K 166960K 1613 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 20 0 NDP 12 0K 2K 166960K 40 0 temp 75 8672K 8736K 166960K 12722 0 kqueue 14 22K 30K 166960K 74 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 120 125 0 122 3 0 3 3 0 8 2 rtentry 136 133 0 43 4 0 4 4 0 8 0 unpcb 144 415 0 400 6 0 6 6 0 8 5 syncache 336 4 0 4 1 0 1 1 0 8 1 tcpqe 32 1 0 1 1 0 1 1 0 8 1 tcpcb 736 92 0 87 2 0 2 2 0 8 0 arp 96 23 0 7 1 0 1 1 0 8 0 ipq 40 1 0 0 1 0 1 1 0 8 0 ipqe 40 2 0 0 1 0 1 1 0 8 0 inpcb 328 407 0 395 7 0 7 7 0 8 5 ip6q 72 3 0 2 1 0 1 1 0 8 0 ip6af 40 4 0 4 1 0 1 1 0 8 1 nd6 112 28 0 6 1 0 1 1 0 8 0 pkpcb 40 39 0 39 1 0 1 1 0 8 1 kcovpl 48 9 0 1 1 0 1 1 0 8 0 ppxss 1072 9 0 6 1 0 1 1 0 8 0 pppxif 1416 1 0 1 1 0 1 1 0 8 1 pfstscr 40 2 0 2 1 0 1 1 0 8 1 pfstkey 128 2 0 2 1 0 1 1 0 8 1 pfstate 384 1 0 1 1 0 1 1 0 8 1 rttmr 136 1 0 1 1 0 1 1 0 8 1 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 547 0 98 29 0 29 29 0 8 0 art_table 40 549 0 98 5 0 5 5 0 8 0 art_node 32 133 0 41 1 0 1 1 0 8 0 sysvmsgpl 40 1 0 0 1 0 1 1 0 8 0 semapl 112 6 0 0 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 2287 0 793 95 0 95 95 0 8 0 ffsino 256 2287 0 793 95 0 95 95 0 8 0 nchpl 144 2995 0 1294 64 0 64 64 0 8 0 rtmask 32 1 0 0 1 0 1 1 0 8 0 vnodes 216 2696 0 0 150 0 150 150 0 8 0 namei 1024 9838 0 9838 2 0 2 2 0 8 2 vcpupl 3904 1 0 0 1 0 1 1 0 8 0 vmpool 808 1 0 0 1 0 1 1 0 8 0 kstatmem 264 42 0 18 2 0 2 2 0 8 0 scsiplug 72 5 0 5 1 0 1 1 0 8 1 scxspl 216 13942 0 13942 8 0 8 8 1 8 8 plimitpl 152 208 0 188 1 0 1 1 0 8 0 sigapl 424 820 0 756 8 0 8 8 0 8 0 knotepl 120 16683 0 16497 13 0 13 13 0 8 7 kqueuepl 184 203 0 192 4 0 4 4 0 8 3 pipepl 304 169 0 142 5 0 5 5 0 8 2 fdescpl 448 786 0 756 5 0 5 5 0 8 1 filepl 120 4335 0 4104 15 0 15 15 0 8 7 lockfpl 104 122 0 118 1 0 1 1 0 8 0 lockfspl 48 55 0 52 1 0 1 1 0 8 0 sessionpl 144 23 0 15 1 0 1 1 0 8 0 pgrppl 48 35 0 19 1 0 1 1 0 8 0 ucredpl 104 417 0 406 1 0 1 1 0 8 0 zombiepl 144 760 0 756 1 0 1 1 0 8 0 processpl 1152 820 0 756 5 0 5 5 0 8 0 procpl 664 1363 0 1294 7 0 7 7 0 8 0 sosppl 176 5 0 5 1 0 1 1 0 8 1 sockpl 552 997 0 967 17 7 10 17 0 8 7 mcl64k 65536 16 0 16 1 0 1 1 0 8 1 mcl8k 8192 7 0 7 1 0 1 1 0 8 1 mcl4k 4096 2944 0 2888 15 0 15 15 0 8 7 mcl2k2 2112 1 0 1 1 0 1 1 0 8 1 mcl2k 2048 873 0 872 2 0 2 2 0 8 1 mtagpl 96 26 0 8 1 0 1 1 0 8 0 mbufpl 256 25831 0 25662 12 0 12 12 0 8 0 bufpl 280 5349 0 119 374 0 374 374 0 8 0 anonpl 24 145382 0 141937 62 0 62 62 0 187 27 amapchunkpl 152 19488 0 18991 30 0 30 30 0 158 10 amappl16 200 2970 0 2922 25 13 12 25 0 8 8 amappl15 192 2 0 2 1 0 1 1 0 8 1 amappl14 184 4 0 4 1 0 1 1 0 8 1 amappl13 176 414 0 412 1 0 1 1 0 8 0 amappl12 168 1133 0 1094 2 0 2 2 0 8 0 amappl11 160 26 0 26 1 0 1 1 0 8 1 amappl10 152 44 0 33 1 0 1 1 0 8 0 amappl9 144 244 0 244 1 0 1 1 0 8 1 amappl8 136 37 0 36 1 0 1 1 0 8 0 amappl7 128 102 0 100 1 0 1 1 0 8 0 amappl6 120 271 0 260 1 0 1 1 0 8 0 amappl5 112 79 0 71 1 0 1 1 0 8 0 amappl4 104 387 0 364 1 0 1 1 0 8 0 amappl3 96 3380 0 3286 3 0 3 3 0 8 0 amappl2 88 899 0 828 2 0 2 2 0 8 0 amappl1 80 10634 0 10090 13 0 13 13 0 8 0 amappl 88 5376 0 5209 5 0 5 5 0 92 0 uvmvnodes 80 106 0 0 3 0 3 3 0 8 0 dma4096 4096 3 0 3 1 0 1 1 0 8 1 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 7 0 7 1 0 1 1 0 8 1 dma128 128 253 0 253 1 0 1 1 0 8 1 dma64 64 6 0 6 1 0 1 1 0 8 1 dma32 32 7 0 7 1 0 1 1 0 8 1 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 16 0 2 1 0 1 1 0 8 0 uaddrrnd 24 786 0 756 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 786 0 756 1 0 1 1 0 8 0 vmmpekpl 168 7920 0 7885 2 0 2 2 0 8 0 vmmpepl 168 57000 0 55147 99 0 99 99 0 357 18 vmsppl 368 785 0 756 4 0 4 4 0 8 1 rwobjpl 40 18186 0 17200 15 0 15 15 0 8 1 pdppl 4096 1581 0 1513 102 34 68 83 0 8 0 pvpl 32 366932 0 356885 137 0 137 137 0 265 50 pmappl 216 786 0 756 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 375 0 34 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(ffff800001565860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806bb52200,ffffffff839adbf8,0,0,ffff80002a739540,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001597980,83,0) 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(ffff80002a72cf90) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72cf90) 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(ffff800001565860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806bb522f0,ffff800001565800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806bb52200,ffffffff839adbf8,0,0,ffff80002a739540,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001597980,83,0) 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(ffff80002a72cf90) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72cf90) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10