panic: maddr rwlock 0xffff80000155b060: enter read deadlock Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 97395 28798 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(ffff80000155b060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd807e07d800,ffffffff839adbf8,0,0,ffff80002a739470,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159f800,83,0) 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 0xffff80000155b060: 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(ffff80000155b060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd807e07d800,ffffffff839adbf8,0,0,ffff80002a739470,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159f800,83,0) 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 0xffff80002a739180 rbx 0xffff80000155b000 rdx 0 rcx 0 rax 0xffff80002a72d4c0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xdecf4a6c8f788093 r11 0xc79fe3989c64e762 r12 0 r13 0xffff80002a72d4c4 r14 0 r15 0x1 rip 0xffffffff82215455 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a739170 ss 0 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=97395 pid=28798 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=0xffff80002a72d758,0xffff80002a72d238 process=0xffff8000ffffdb00 user=0xffff80002a734000, vmspace=0xffffffff839ad710 estcpu=0, cpticks=2, pctcpu=0.0, user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 59679 443276 13500 0 2 0 syz-executor 59679 264312 13500 0 3 0x4000080 fsleep syz-executor 52054 308997 54561 0 2 0 syz-executor 52054 332855 54561 0 3 0x4000080 fsleep syz-executor 52054 2224 54561 0 3 0x4000080 fsleep syz-executor 65794 125450 58888 0 2 0 syz-executor 65794 51552 58888 0 3 0x4000080 fsleep syz-executor 87375 454481 21665 60929 2 0x10 syz-executor 87375 514257 21665 60929 3 0x4000090 fsleep syz-executor 58833 33978 21669 0 3 0x80 nanoslp syz-executor 58833 378469 21669 0 3 0x4000080 semwait syz-executor 58833 38316 21669 0 3 0x4000080 fsleep syz-executor 58833 186363 21669 0 3 0x4000080 fsleep syz-executor 21665 140486 32904 0 3 0x82 nanoslp syz-executor 70035 339990 0 0 3 0x14200 acct acct 13500 15557 32904 0 3 0x82 nanoslp syz-executor 97673 448785 32904 0 3 0x82 nanoslp syz-executor 54561 395708 32904 0 3 0x82 nanoslp syz-executor 21669 284984 32904 0 3 0x82 nanoslp syz-executor 83253 237719 32904 0 2 0x2 syz-executor 58888 384464 32904 0 3 0x82 nanoslp syz-executor 81327 445789 32904 0 2 0x2 syz-executor 32904 288965 16634 0 3 0x82 kqread syz-executor 16634 200816 80394 0 3 0x10008a sigsusp ksh 80394 98550 98461 0 3 0x98 kqread sshd-session 98461 142210 27104 0 3 0x92 kqread sshd-session 69311 240443 1 0 3 0x100083 ttyopn getty 27104 320430 1 0 3 0x88 kqread sshd 19137 100187 79952 73 3 0x1100090 kqread syslogd 79952 405847 1 0 3 0x100082 sbwait syslogd 46365 120682 1 0 3 0x100080 kqread resolvd 25295 468468 63948 77 3 0x100092 kqread dhcpleased 96997 16564 63948 77 3 0x100092 kqread dhcpleased 63948 232108 1 0 3 0x80 kqread dhcpleased 79146 109364 0 0 3 0x14200 bored smr 22693 368921 0 0 2 0x14200 zerothread 82141 25946 0 0 3 0x14200 aiodoned aiodoned 62933 151022 0 0 3 0x14200 syncer update 22788 181740 0 0 3 0x14200 cleaner cleaner 32374 424362 0 0 3 0x14200 reaper reaper 88410 234490 0 0 3 0x14200 pgdaemon pagedaemon 56122 390125 0 0 3 0x14200 bored viomb 78935 424678 0 0 3 0x40014200 acpi0 acpi0 75079 262311 0 0 3 0x14200 bored softnet0 4096 432916 0 0 3 0x14200 bored systqmp 5641 39957 0 0 3 0x14200 bored systq *28798 97395 0 0 7 0x40014200 softclock 52717 15218 0 0 3 0x40014200 idle0 1 73016 0 0 3 0x82 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 11035 12119K 13235K 166960K 13414 0 pcb 19 18K 23K 166960K 409 0 rtable 228 10K 10K 166960K 484 0 pf 28 12K 17K 166960K 89 0 ifaddr 34 6K 7K 166960K 78 0 ifgroup 44 1K 2K 166960K 114 0 sysctl 3 1K 9K 166960K 8 0 counters 32 17K 18K 166960K 78 0 ioctlops 0 0K 4K 166960K 299 0 iov 0 0K 12K 166960K 27 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1454 91K 92K 166960K 2161 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 2K 6K 166960K 10 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 22 0 dirhash 12 2K 3K 166960K 27 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 16 57K 93K 166960K 722 0 sigio 0 0K 0K 166960K 53 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 0 0K 0K 166960K 63 0 in_multi 73 5K 7K 166960K 133 0 ether_multi 1 0K 0K 166960K 6 0 mrt 2 0K 0K 166960K 8 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 91 413K 413K 166960K 91 0 exec 0 0K 1K 166960K 511 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 3 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 223 159K 174K 166960K 8390 0 UVM aobj 16 6K 6K 166960K 31 0 pinsyscall 37 74K 94K 166960K 1831 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 45 0 NDP 10 0K 2K 166960K 54 0 temp 78 8672K 8928K 166960K 29221 0 kqueue 15 24K 30K 166960K 112 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 120 215 0 212 5 0 5 5 0 8 4 rtentry 136 135 0 46 4 0 4 4 0 8 0 unpcb 144 395 0 380 4 0 4 4 0 8 3 syncache 336 5 0 5 2 1 1 1 0 8 1 tcpqe 32 3 0 3 2 1 1 1 0 8 1 tcpcb 736 356 0 349 13 6 7 7 0 8 6 arp 96 20 0 6 1 0 1 1 0 8 0 ipq 40 8 0 2 1 0 1 1 0 8 0 ipqe 40 13 0 7 1 0 1 1 0 8 0 inpcb 328 1178 0 1163 19 9 10 12 0 8 8 ip6q 72 1 0 1 1 1 0 1 0 8 0 ip6af 40 2 0 2 1 1 0 1 0 8 0 nd6 112 30 0 13 1 0 1 1 0 8 0 pkpcb 40 3 0 3 2 1 1 1 0 8 1 kcovpl 48 9 0 1 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 0 1 1 0 8 1 ppxss 1072 39 0 38 2 1 1 1 0 8 0 pppxif 1416 2 0 2 2 1 1 1 0 8 1 pfanchor 1288 4 0 0 1 0 1 1 0 8 0 pfrule 1344 1 0 0 1 0 1 1 0 8 0 rttmr 136 2 0 1 2 1 1 1 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 602 0 217 29 2 27 29 0 8 2 art_table 40 604 0 217 5 0 5 5 0 8 0 art_node 32 134 0 52 1 0 1 1 0 8 0 sysvmsgpl 40 3 0 2 1 0 1 1 0 8 0 semapl 112 18 0 8 1 0 1 1 0 8 0 shmpl 112 26 0 15 1 0 1 1 0 8 0 dirhash 1024 27 0 10 3 0 3 3 0 8 0 dino2pl 256 2830 0 1335 95 0 95 95 0 8 0 ffsino 256 2830 0 1335 95 0 95 95 0 8 0 nchpl 144 3765 0 2070 64 0 64 64 0 8 0 rtmask 32 14 0 14 2 1 1 1 0 8 1 vnodes 216 3314 0 0 185 0 185 185 0 8 0 namei 1024 12760 0 12758 3 2 1 1 0 8 0 vcpupl 3904 2 0 0 1 0 1 1 0 8 0 vmpool 808 2 0 0 1 0 1 1 0 8 0 kstatmem 264 70 0 50 2 0 2 2 0 8 0 scsiplug 72 5 0 5 2 1 1 1 0 8 1 scxspl 216 13621 0 13621 10 2 8 8 1 8 8 plimitpl 152 151 0 135 1 0 1 1 0 8 0 sigapl 424 1015 0 973 7 1 6 6 0 8 1 knotepl 120 25749 0 25699 18 8 10 10 0 8 8 kqueuepl 184 169 0 157 1 0 1 1 0 8 0 pipepl 304 159 0 132 3 0 3 3 0 8 0 fdescpl 448 997 0 969 5 1 4 5 0 8 0 filepl 120 6593 0 6380 15 1 14 14 0 8 5 lockfpl 104 274 0 272 1 0 1 1 0 8 0 lockfspl 48 92 0 90 1 0 1 1 0 8 0 sessionpl 144 23 0 15 1 0 1 1 0 8 0 pgrppl 48 37 0 21 1 0 1 1 0 8 0 ucredpl 104 1208 0 1196 1 0 1 1 0 8 0 zombiepl 144 1240 0 1239 1 0 1 1 0 8 0 processpl 1152 1015 0 973 4 0 4 4 0 8 0 procpl 664 1965 0 1915 7 1 6 6 0 8 0 sosppl 176 5 0 5 1 0 1 1 0 8 1 sockpl 552 1838 0 1805 19 8 11 12 0 8 8 mcl64k 65536 160 0 160 2 1 1 1 0 8 1 mcl16k 16384 7 0 7 1 0 1 1 0 8 1 mcl12k 12288 2 0 2 2 1 1 1 0 8 1 mcl8k 8192 10 0 10 2 1 1 1 0 8 1 mcl4k 4096 3227 0 3175 15 7 8 14 0 8 1 mcl2k 2048 1047 0 1044 3 1 2 2 0 8 1 mtagpl 96 39 0 12 1 0 1 1 0 8 0 mbufpl 256 10574 0 10373 20 0 20 20 0 8 4 bufpl 280 4427 0 122 308 0 308 308 0 8 0 anonpl 24 166181 0 163141 60 12 48 48 0 187 9 amapchunkpl 152 27660 0 27216 38 5 33 33 0 158 13 amappl16 200 2632 0 2603 24 11 13 15 0 8 8 amappl15 192 17 0 17 1 1 0 1 0 8 0 amappl14 184 5 0 5 2 1 1 1 0 8 1 amappl13 176 434 0 433 1 0 1 1 0 8 0 amappl12 168 1351 0 1314 2 0 2 2 0 8 0 amappl11 160 6 0 6 1 1 0 1 0 8 0 amappl10 152 43 0 33 1 0 1 1 0 8 0 amappl9 144 270 0 270 1 1 0 1 0 8 0 amappl8 136 21 0 20 1 0 1 1 0 8 0 amappl7 128 103 0 102 1 0 1 1 0 8 0 amappl6 120 275 0 264 1 0 1 1 0 8 0 amappl5 112 68 0 61 1 0 1 1 0 8 0 amappl4 104 386 0 362 1 0 1 1 0 8 0 amappl3 96 4637 0 4555 3 0 3 3 0 8 0 amappl2 88 1118 0 1049 2 0 2 2 0 8 0 amappl1 80 11524 0 10991 14 1 13 13 0 8 0 amappl 88 7559 0 7407 6 1 5 5 0 92 0 uvmvnodes 80 116 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 dma512 512 1 0 1 1 0 1 1 0 8 1 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 254 0 254 2 1 1 1 0 8 1 dma64 64 7 0 7 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 30 0 15 1 0 1 1 0 8 0 uaddrrnd 24 997 0 969 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 997 0 969 1 0 1 1 0 8 0 vmmpekpl 168 9423 0 9387 2 0 2 2 0 8 0 vmmpepl 168 69200 0 67475 102 10 92 92 0 357 10 vmsppl 368 996 0 969 4 1 3 4 0 8 0 rwobjpl 40 20262 0 19308 13 0 13 13 0 8 0 pdppl 4096 2005 0 1940 99 30 69 81 0 8 4 pvpl 32 447179 0 438852 141 26 115 115 0 265 15 pmappl 216 998 0 969 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 399 0 55 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(ffff80000155b060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd807e07d800,ffffffff839adbf8,0,0,ffff80002a739470,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159f800,83,0) 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(ffff80000155b060,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd807e07d8f0,ffff80000155b000) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd807e07d800,ffffffff839adbf8,0,0,ffff80002a739470,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff80000159f800,83,0) 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