panic: maddr rwlock 0xffff800001584060: enter read deadlock Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *231219 48318 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(ffff800001584060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd8065f6f900,ffffffff839adbf8,0,0,ffff80002a738fc0,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff8000015a2400,83,0) 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(ffff80002a72d228) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d228) 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 0xffff800001584060: 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(ffff800001584060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd8065f6f900,ffffffff839adbf8,0,0,ffff80002a738fc0,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff8000015a2400,83,0) 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(ffff80002a72d228) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d228) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002a738cd0 rbx 0xffff800001584000 rdx 0 rcx 0 rax 0xffff80002a72d228 r8 0x101010101010101 r9 0x8080808080808080 r10 0xcc1059d5fe7a60a7 r11 0x6a89afbea05801fd r12 0 r13 0xffff80002a72d22c r14 0 r15 0x1 rip 0xffffffff82215455 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a738cc0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=231219 pid=48318 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=0xffff80002a72d758,0xffff80002a72ca70 process=0xffff8000fffff180 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 38826 493536 70986 0 2 0 syz-executor 38826 282301 70986 0 2 0x4000080 syz-executor 61831 122414 93365 0 3 0x80 nanoslp syz-executor 61831 25534 93365 0 3 0x4000080 kqread syz-executor 61831 457650 93365 0 3 0x4000080 fsleep syz-executor 4984 11939 6494 0 2 0 syz-executor 4984 363072 6494 0 2 0x4000000 syz-executor 63780 407377 47440 0 2 0xc80 syz-executor 63780 163925 47440 0 3 0x4000080 kqread syz-executor 63780 398353 47440 0 3 0x4000080 fsleep syz-executor 73012 361314 42496 0 3 0x80 nanoslp syz-executor 73012 355803 42496 0 3 0x4000080 fsleep syz-executor 73012 187224 42496 0 3 0x4000080 ttyopn syz-executor 73012 311157 42496 0 3 0x4000080 ttyopn syz-executor 52576 386615 0 0 3 0x14280 nfsidl nfsio 86207 20568 0 0 3 0x14280 nfsidl nfsio 218 180063 0 0 3 0x14280 nfsidl nfsio 93534 472398 0 0 3 0x14280 nfsidl nfsio 55411 482332 0 0 3 0x14280 nfsidl nfsio 43849 369418 0 0 3 0x14280 nfsidl nfsio 47409 426043 0 0 3 0x14280 nfsidl nfsio 31280 57033 0 0 3 0x14280 nfsidl nfsio 69001 521437 0 0 3 0x14280 nfsidl nfsio 43419 472286 0 0 3 0x14280 nfsidl nfsio 99360 200097 0 0 3 0x14280 nfsidl nfsio 71057 239613 0 0 3 0x14280 nfsidl nfsio 2074 149659 0 0 3 0x14280 nfsidl nfsio 21057 477562 0 0 3 0x14280 nfsidl nfsio 75191 276136 0 0 3 0x14280 nfsidl nfsio 31685 120504 0 0 3 0x14280 nfsidl nfsio 34718 269436 0 0 3 0x14280 nfsidl nfsio 13661 119994 0 0 3 0x14280 nfsidl nfsio 73113 257165 0 0 3 0x14280 nfsidl nfsio 98196 398814 0 0 3 0x14280 nfsidl nfsio 47440 297375 95386 0 2 0xc82 syz-executor 90296 429523 95386 0 2 0x2 syz-executor 6494 263664 95386 0 3 0x82 nanoslp syz-executor 42496 320562 95386 0 2 0xc82 syz-executor 37054 175708 95386 0 3 0x82 nanoslp syz-executor 70986 316878 95386 0 3 0x82 nanoslp syz-executor 93365 227429 95386 0 3 0x82 nanoslp syz-executor 45752 313126 95386 0 2 0x2 syz-executor 95386 216132 12891 0 3 0x82 kqread syz-executor 12891 512129 77197 0 3 0x10008a sigsusp ksh 77197 87865 55773 0 3 0x98 kqread sshd-session 55773 321233 62224 0 3 0x92 kqread sshd-session 57202 275090 1 0 3 0x100083 ttyin getty 62224 70968 1 0 3 0x88 kqread sshd 82 302877 49200 73 3 0x1100090 kqread syslogd 49200 64914 1 0 3 0x100082 sbwait syslogd 83573 346546 1 0 3 0x100080 kqread resolvd 18557 313937 79311 77 3 0x100092 kqread dhcpleased 4220 440929 79311 77 3 0x100092 kqread dhcpleased 79311 116510 1 0 3 0x80 kqread dhcpleased 92454 166115 0 0 3 0x14200 bored smr 7603 263059 0 0 2 0x14200 zerothread 47661 108983 0 0 3 0x14200 aiodoned aiodoned 53395 298335 0 0 3 0x14200 syncer update 1927 155238 0 0 3 0x14200 cleaner cleaner 93436 89435 0 0 3 0x14200 reaper reaper 65044 498213 0 0 3 0x14200 pgdaemon pagedaemon 95658 275930 0 0 3 0x14200 bored viomb 64078 418653 0 0 3 0x40014200 acpi0 acpi0 11767 383139 0 0 3 0x14200 bored softnet0 71354 353356 0 0 3 0x14200 bored systqmp 47842 388680 0 0 3 0x14200 bored systq *48318 231219 0 0 7 0x40014200 softclock 84545 102212 0 0 3 0x40014200 idle0 1 368459 0 0 3 0x80082 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11041 12180K 12540K 166960K 12998 0 pcb 18 14K 15K 166960K 116 0 rtable 258 9K 9K 166960K 406 0 pf 33 13K 17K 166960K 64 0 ifaddr 43 7K 8K 166960K 63 0 ifgroup 52 2K 2K 166960K 87 0 sysctl 1 1K 9K 166960K 8 0 counters 36 18K 18K 166960K 54 0 ioctlops 0 0K 4K 166960K 109 0 iov 0 0K 12K 166960K 8 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1413 89K 90K 166960K 1690 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 6 0 VM map 2 1K 1K 166960K 2 0 sem 4 0K 0K 166960K 7 0 dirhash 12 2K 2K 166960K 21 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 16 57K 97K 166960K 358 0 sigio 1 0K 0K 166960K 70 0 proc 60 59K 124K 166960K 487 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 94 0 in_multi 99 7K 7K 166960K 112 0 ether_multi 1 0K 0K 166960K 2 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 67 307K 307K 166960K 67 0 exec 0 0K 1K 166960K 388 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 151K 170K 166960K 4936 0 UVM aobj 9 8K 8K 166960K 12 0 pinsyscall 37 74K 96K 166960K 1436 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 16 0 NDP 12 0K 2K 166960K 40 0 temp 46 8664K 8728K 166960K 12354 0 kqueue 15 24K 30K 166960K 74 0 SYN cache 2 8K 16K 166960K 3 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 151 0 148 3 0 3 3 0 8 2 rtentry 136 120 0 9 4 0 4 4 0 8 0 unpcb 144 399 0 382 4 0 4 4 0 8 3 syncache 336 6 0 6 1 0 1 1 0 8 1 tcpqe 32 1 0 1 1 0 1 1 0 8 1 tcpcb 736 237 0 229 10 1 9 10 0 8 8 arp 96 19 0 1 1 0 1 1 0 8 0 inpcb 328 607 0 591 10 0 10 10 0 8 7 nd6 112 24 0 0 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1072 17 0 14 1 0 1 1 0 8 0 pppxif 1416 3 0 3 1 0 1 1 0 8 1 pftag 88 1 0 0 1 0 1 1 0 8 0 pfstitem 24 2 0 0 1 0 1 1 0 8 0 pfstkey 128 2 0 0 1 0 1 1 0 8 0 pfstate 384 1 0 0 1 0 1 1 0 8 0 pfrule 1344 2 0 1 1 0 1 1 0 8 0 art_heap8 4096 2 0 1 2 0 2 2 0 8 1 art_heap4 256 478 0 26 30 0 30 30 0 8 0 art_table 40 480 0 27 5 0 5 5 0 8 0 art_node 32 119 0 19 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 5 0 3 1 0 1 1 0 8 0 shmpl 112 7 0 2 1 0 1 1 0 8 0 dirhash 1024 23 0 6 3 0 3 3 0 8 0 dino2pl 256 2029 0 528 95 0 95 95 0 8 0 ffsino 256 2029 0 528 95 0 95 95 0 8 0 nchpl 144 2507 0 815 64 0 64 64 0 8 0 rtmask 32 1 0 1 1 0 1 1 0 8 1 vnodes 216 2331 0 0 130 0 130 130 0 8 0 namei 1024 8344 0 8341 2 0 2 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 48 0 24 3 0 3 3 0 8 1 scsiplug 72 1 0 1 1 0 1 1 0 8 1 scxspl 216 7766 0 7766 2 0 2 2 1 8 2 plimitpl 152 113 0 95 1 0 1 1 0 8 0 sigapl 424 670 0 609 8 0 8 8 0 8 0 knotepl 120 15403 0 15353 16 0 16 16 0 8 14 kqueuepl 184 110 0 96 2 0 2 2 0 8 1 pipepl 304 128 0 100 3 0 3 3 0 8 0 fdescpl 448 633 0 605 5 0 5 5 0 8 1 filepl 120 4003 0 3771 13 0 13 13 0 8 4 lockfpl 104 292 0 289 2 0 2 2 0 8 1 lockfspl 48 42 0 39 1 0 1 1 0 8 0 sessionpl 144 23 0 15 1 0 1 1 0 8 0 pgrppl 48 38 0 22 1 0 1 1 0 8 0 ucredpl 104 376 0 365 1 0 1 1 0 8 0 zombiepl 144 610 0 609 1 0 1 1 0 8 0 processpl 1152 670 0 609 5 0 5 5 0 8 0 procpl 664 1030 0 960 7 0 7 7 0 8 0 sosppl 176 3 0 3 1 0 1 1 0 8 1 sockpl 552 1163 0 1127 14 3 11 13 0 8 7 mcl64k 65536 120 0 120 1 0 1 1 0 8 1 mcl16k 16384 6 0 6 1 0 1 1 0 8 1 mcl8k 8192 15 0 15 1 0 1 1 0 8 1 mcl4k 4096 2814 0 2763 14 0 14 14 0 8 7 mcl2k2 2112 1 0 1 1 0 1 1 0 8 1 mcl2k 2048 490 0 487 1 0 1 1 0 8 0 mtagpl 96 80 0 6 2 0 2 2 0 8 0 mbufpl 256 10238 0 10003 20 1 19 20 0 8 3 bufpl 280 2653 0 120 181 0 181 181 0 8 0 anonpl 24 114151 0 111079 57 0 57 57 0 187 29 amapchunkpl 152 15934 0 15465 33 0 33 33 0 158 11 amappl16 200 1606 0 1579 15 0 15 15 0 8 12 amappl15 192 4 0 4 1 0 1 1 0 8 1 amappl14 184 4 0 3 1 0 1 1 0 8 0 amappl13 176 404 0 403 1 0 1 1 0 8 0 amappl12 168 975 0 938 2 0 2 2 0 8 0 amappl11 160 5 0 5 1 0 1 1 0 8 1 amappl10 152 57 0 47 1 0 1 1 0 8 0 amappl9 144 270 0 269 1 0 1 1 0 8 0 amappl8 136 18 0 17 1 0 1 1 0 8 0 amappl7 128 82 0 81 1 0 1 1 0 8 0 amappl6 120 274 0 263 1 0 1 1 0 8 0 amappl5 112 67 0 59 1 0 1 1 0 8 0 amappl4 104 380 0 357 1 0 1 1 0 8 0 amappl3 96 2500 0 2414 3 0 3 3 0 8 0 amappl2 88 752 0 683 2 0 2 2 0 8 0 amappl1 80 10254 0 9723 13 0 13 13 0 8 0 amappl 88 4201 0 4042 5 0 5 5 0 92 0 uvmvnodes 80 102 0 0 3 0 3 3 0 8 0 dma8192 8192 1 0 1 1 0 1 1 0 8 1 dma4096 4096 1 0 1 1 0 1 1 0 8 1 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 0 1 1 0 8 1 dma128 128 253 0 253 1 0 1 1 0 8 1 dma64 64 7 0 7 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 11 0 3 1 0 1 1 0 8 0 uaddrrnd 24 633 0 605 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 633 0 605 1 0 1 1 0 8 0 vmmpekpl 168 6865 0 6836 2 0 2 2 0 8 0 vmmpepl 168 47600 0 45871 91 0 91 91 0 357 8 vmsppl 368 632 0 605 4 0 4 4 0 8 1 rwobjpl 40 15476 0 14533 13 0 13 13 0 8 0 pdppl 4096 1277 0 1213 104 36 68 83 0 8 4 pvpl 32 291116 0 282656 140 0 140 140 0 265 50 pmappl 216 634 0 606 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 394 0 38 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(ffff800001584060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd8065f6f900,ffffffff839adbf8,0,0,ffff80002a738fc0,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff8000015a2400,83,0) 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(ffff80002a72d228) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d228) 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(ffff800001584060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd8065f6f9f0,ffff800001584000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd8065f6f900,ffffffff839adbf8,0,0,ffff80002a738fc0,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff8000015a2400,83,0) 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(ffff80002a72d228) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d228) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10