panic: maddr rwlock 0xffff800001580860: enter read deadlock Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *128882 55618 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(ffff800001580860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806c941c00,ffffffff839adbf8,0,0,ffff80002a739780,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001598a80,83,0) 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(ffff80002a72d758) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d758) 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 0xffff800001580860: 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(ffff800001580860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806c941c00,ffffffff839adbf8,0,0,ffff80002a739780,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001598a80,83,0) 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(ffff80002a72d758) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d758) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002a739490 rbx 0xffff800001580800 rdx 0 rcx 0 rax 0xffff80002a72d758 r8 0x101010101010101 r9 0x8080808080808080 r10 0xbb50e1a8d37c94f r11 0x18f516eee8bb4869 r12 0 r13 0xffff80002a72d75c r14 0 r15 0x1 rip 0xffffffff82215455 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a739480 ss 0 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=128882 pid=55618 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=0xffff80002a72d9f0,0xffff80002a72d4d0 process=0xffff8000ffffe880 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 99561 292862 43373 0 3 0x3000 suspend syz-executor 99561 164892 43373 0 2 0x4081000 syz-executor 54998 153117 74460 0 2 0 syz-executor 54998 363890 74460 0 3 0x4000080 tunread syz-executor 5403 364940 2459 0 2 0 syz-executor 5403 78311 2459 0 3 0x4000080 fsleep syz-executor 45700 134310 32567 0 3 0x82 sbwait sshd-session 1172 325538 92795 0 2 0 syz-executor 1172 426838 92795 0 3 0x4000080 ttyin syz-executor 1172 230349 92795 0 2 0x4000000 syz-executor 39050 235598 65621 0 2 0 syz-executor 39050 173845 65621 0 2 0x4000c80 syz-executor 15238 181600 93858 0 2 0xc80 syz-executor 15238 245153 93858 0 3 0x4000080 lockf syz-executor 15238 13678 93858 0 3 0x4000080 fsleep syz-executor 39539 114817 92362 0 3 0x3000 suspend syz-executor 39539 56533 92362 0 2 0x4081000 syz-executor 94923 192238 0 0 3 0x14280 nfsidl nfsio 21540 185205 0 0 3 0x14280 nfsidl nfsio 34959 323605 0 0 3 0x14280 nfsidl nfsio 80596 247157 0 0 3 0x14280 nfsidl nfsio 32457 364868 0 0 3 0x14280 nfsidl nfsio 61846 363557 0 0 3 0x14280 nfsidl nfsio 66836 169790 0 0 3 0x14280 nfsidl nfsio 88836 272480 0 0 3 0x14280 nfsidl nfsio 21804 370183 0 0 3 0x14280 nfsidl nfsio 1294 339148 0 0 3 0x14280 nfsidl nfsio 49001 442551 0 0 3 0x14280 nfsidl nfsio 83300 290949 0 0 3 0x14280 nfsidl nfsio 50585 267549 0 0 3 0x14280 nfsidl nfsio 51344 84399 0 0 3 0x14280 nfsidl nfsio 48353 136391 0 0 3 0x14280 nfsidl nfsio 78305 345800 0 0 3 0x14280 nfsidl nfsio 90153 317312 0 0 3 0x14280 nfsidl nfsio 52470 44899 0 0 3 0x14280 nfsidl nfsio 46359 424654 0 0 3 0x14280 nfsidl nfsio 56133 450838 0 0 3 0x14280 nfsidl nfsio 43373 67458 73180 0 2 0xc82 syz-executor 65621 39758 73180 0 3 0x82 nanoslp syz-executor 93858 251559 73180 0 3 0x82 nanoslp syz-executor 92362 150408 73180 0 2 0xc82 syz-executor 2459 162073 73180 0 2 0xc82 syz-executor 21157 381113 73180 0 2 0x2 syz-executor 74460 65709 73180 0 2 0xc82 syz-executor 92795 396392 73180 0 2 0xc82 syz-executor 73180 230878 99617 0 2 0x2 syz-executor 99617 483921 78542 0 3 0x10008a sigsusp ksh 78542 221693 16665 0 3 0x98 kqread sshd-session 16665 465275 32567 0 3 0x92 kqread sshd-session 46720 470085 1 0 3 0x100083 ttyin getty 32567 449111 1 0 3 0x88 kqread sshd 10414 6723 80414 73 3 0x1100090 kqread syslogd 80414 265540 1 0 3 0x100082 sbwait syslogd 845 474144 1 0 3 0x100080 kqread resolvd 41682 259180 31046 77 3 0x100092 kqread dhcpleased 14999 13929 31046 77 3 0x100092 kqread dhcpleased 31046 199740 1 0 3 0x80 kqread dhcpleased 48203 490736 0 0 3 0x14200 bored smr 5866 165946 0 0 2 0x14200 zerothread 5120 292175 0 0 3 0x14200 aiodoned aiodoned 3289 133020 0 0 3 0x14200 syncer update 91643 299256 0 0 3 0x14200 cleaner cleaner 9283 207469 0 0 3 0x14200 reaper reaper 86601 213289 0 0 3 0x14200 pgdaemon pagedaemon 94498 391640 0 0 3 0x14200 bored viomb 64542 336777 0 0 3 0x40014200 acpi0 acpi0 75906 212786 0 0 3 0x14200 bored softnet0 80294 21472 0 0 3 0x14200 bored systqmp 43143 473348 0 0 3 0x14200 bored systq *55618 128882 0 0 7 0x40014200 softclock 31751 422918 0 0 3 0x40014200 idle0 1 500811 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 11040 12234K 12588K 166960K 12372 0 pcb 18 12K 12K 166960K 32 0 rtable 241 7K 7K 166960K 364 0 pf 34 13K 13K 166960K 48 0 ifaddr 43 7K 7K 166960K 54 0 ifgroup 55 2K 2K 166960K 74 0 sysctl 1 1K 9K 166960K 5 0 counters 34 17K 18K 166960K 44 0 ioctlops 0 0K 4K 166960K 47 0 iov 0 0K 14K 166960K 9 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1369 86K 87K 166960K 1557 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 1K 166960K 2 0 VM map 2 1K 1K 166960K 2 0 sem 3 0K 0K 166960K 3 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 93K 166960K 239 0 sigio 0 0K 0K 166960K 2 0 proc 60 59K 91K 166960K 486 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 8 0 in_multi 99 7K 7K 166960K 105 0 ether_multi 1 0K 0K 166960K 3 0 mrt 2 0K 0K 166960K 3 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 55 254K 254K 166960K 55 0 exec 0 0K 1K 166960K 373 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 240 159K 160K 166960K 3952 0 UVM aobj 3 2K 2K 166960K 3 0 pinsyscall 40 80K 94K 166960K 1317 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 7 0 NDP 12 0K 1K 166960K 33 0 temp 38 8663K 8728K 166960K 8556 0 kqueue 14 22K 26K 166960K 48 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 43 0 38 1 0 1 1 0 8 0 rtentry 136 113 0 3 4 0 4 4 0 8 0 unpcb 144 111 0 94 1 0 1 1 0 8 0 syncache 336 5 0 5 1 0 1 1 0 8 1 tcpcb 736 37 0 31 1 0 1 1 0 8 0 arp 96 18 0 0 1 0 1 1 0 8 0 ipq 40 4 0 2 1 0 1 1 0 8 0 ipqe 40 38 0 36 1 0 1 1 0 8 0 inpcb 328 117 0 107 2 0 2 2 0 8 1 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 7 0 7 1 0 1 1 0 8 1 pppxif 1416 2 0 2 1 0 1 1 0 8 1 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 465 0 12 29 0 29 29 0 8 0 art_table 40 466 0 12 5 0 5 5 0 8 0 art_node 32 113 0 13 1 0 1 1 0 8 0 semapl 112 1 0 0 1 0 1 1 0 8 0 dirhash 1024 19 0 2 3 0 3 3 0 8 0 dino2pl 256 1828 0 325 95 0 95 95 0 8 0 ffsino 256 1828 0 325 95 0 95 95 0 8 0 nchpl 144 2172 0 480 64 0 64 64 0 8 0 rtmask 32 2 0 2 1 0 1 1 0 8 1 vnodes 216 2003 0 0 112 0 112 112 0 8 0 namei 1024 6756 0 6755 1 0 1 1 0 8 0 kstatmem 264 34 0 10 2 0 2 2 0 8 0 scxspl 216 7277 0 7277 2 0 2 2 1 8 2 plimitpl 152 50 0 32 1 0 1 1 0 8 0 sigapl 424 547 0 484 8 0 8 8 0 8 0 knotepl 120 6273 0 6220 2 0 2 2 0 8 0 kqueuepl 184 57 0 46 1 0 1 1 0 8 0 pipepl 304 123 0 96 3 0 3 3 0 8 0 fdescpl 448 514 0 484 5 0 5 5 0 8 1 filepl 120 2362 0 2141 10 0 10 10 0 8 2 lockfpl 104 175 0 171 2 0 2 2 0 8 1 lockfspl 48 21 0 18 1 0 1 1 0 8 0 sessionpl 144 23 0 14 1 0 1 1 0 8 0 pgrppl 48 34 0 17 1 0 1 1 0 8 0 ucredpl 104 451 0 439 1 0 1 1 0 8 0 zombiepl 144 486 0 484 1 0 1 1 0 8 0 processpl 1152 547 0 484 5 0 5 5 0 8 0 procpl 664 718 0 646 7 0 7 7 0 8 0 sockpl 552 278 0 246 4 0 4 4 0 8 1 mcl64k 65536 52 0 51 3 0 3 3 0 8 2 mcl8k 8192 10 0 10 1 0 1 1 0 8 1 mcl4k 4096 2589 0 2534 15 0 15 15 0 8 7 mcl2k 2048 414 0 412 2 0 2 2 0 8 1 mtagpl 96 6 0 4 1 0 1 1 0 8 0 mbufpl 256 5256 0 5091 12 0 12 12 0 8 0 bufpl 280 2518 0 120 172 0 172 172 0 8 0 anonpl 24 112222 0 108888 57 0 57 57 0 187 29 amapchunkpl 152 11537 0 11047 26 0 26 26 0 158 6 amappl16 200 2192 0 2167 14 3 11 14 0 8 8 amappl15 192 93 0 92 1 0 1 1 0 8 0 amappl14 184 9 0 9 1 0 1 1 0 8 1 amappl13 176 409 0 407 1 0 1 1 0 8 0 amappl12 168 857 0 817 2 0 2 2 0 8 0 amappl11 160 101 0 101 1 0 1 1 0 8 1 amappl10 152 48 0 38 1 0 1 1 0 8 0 amappl9 144 241 0 241 1 0 1 1 0 8 1 amappl8 136 108 0 107 1 0 1 1 0 8 0 amappl7 128 80 0 79 1 0 1 1 0 8 0 amappl6 120 267 0 255 1 0 1 1 0 8 0 amappl5 112 74 0 66 1 0 1 1 0 8 0 amappl4 104 464 0 438 1 0 1 1 0 8 0 amappl3 96 1819 0 1729 3 0 3 3 0 8 0 amappl2 88 641 0 563 2 0 2 2 0 8 0 amappl1 80 9728 0 9109 13 0 13 13 0 8 0 amappl 88 3227 0 3062 4 0 4 4 0 92 0 uvmvnodes 80 101 0 0 3 0 3 3 0 8 0 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 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 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 514 0 484 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 514 0 484 1 0 1 1 0 8 0 vmmpekpl 168 6010 0 5985 2 0 2 2 0 8 0 vmmpepl 168 42950 0 41040 90 0 90 90 0 357 4 vmsppl 368 513 0 484 4 0 4 4 0 8 1 rwobjpl 40 14875 0 13834 13 0 13 13 0 8 0 pdppl 4096 1035 0 968 101 32 69 81 0 8 2 pvpl 32 266677 0 256724 130 0 130 130 0 265 36 pmappl 216 513 0 484 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 372 0 32 10 0 10 10 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(ffff800001580860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806c941c00,ffffffff839adbf8,0,0,ffff80002a739780,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001598a80,83,0) 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(ffff80002a72d758) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d758) 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(ffff800001580860,0) at rw_do_enter_read+0x435 sys/kern/kern_rwlock.c:379 in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 in6_lookupmulti sys/netinet6/in6.c:-1 [inline] in6_hasmulti(fffffd806c941cf0,ffff800001580800) at in6_hasmulti+0x41 sys/netinet6/in6.c:1150 ip6_output(fffffd806c941c00,ffffffff839adbf8,0,0,ffff80002a739780,0) at ip6_output+0x1369 sys/netinet6/ip6_output.c:507 mld6_sendpkt(ffff800001598a80,83,0) 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(ffff80002a72d758) at softclock_thread+0x12b softclock_thread_run sys/kern/kern_timeout.c:842 [inline] softclock_thread(ffff80002a72d758) at softclock_thread+0x12b sys/kern/kern_timeout.c:866 end trace frame: 0x0, count: -10