witness: userret: returning with the following locks held: shared rwlock netlock r = 0 (0xffffffff83874a10) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x36e sys/kern/kern_rwlock.c:397 #2 sysctl_file+0x17e6 sys/kern/kern_sysctl.c:1769 #3 kern_sysctl+0x251 sys/kern/kern_sysctl.c:526 #4 sys_sysctl+0x3f2 sys/kern/kern_sysctl.c:-1 #5 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:579 #6 Xsyscall+0x128 panic: witness_warn Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 123902 17890 0 0 0 1 syz-executor *141253 18844 -1 0x10 0x4000000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8338bf48) at panic+0x1e5 sys/kern/subr_prf.c:198 witness_warn(2,0,ffffffff83344572) at witness_warn+0x850 witness_debugger sys/kern/subr_witness.c:2576 [inline] witness_warn(2,0,ffffffff83344572) at witness_warn+0x850 sys/kern/subr_witness.c:1485 userret(ffff80002a297730) at userret+0x3a4 sys/kern/kern_sig.c:2227 syscall(ffff800031be8ff0) at syscall+0x9c0 mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff800031be8ff0) at syscall+0x9c0 sys/arch/amd64/amd64/trap.c:600 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf4a7ff5e0d0, count: 9 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: witness_warn ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8338bf48) at panic+0x1e5 sys/kern/subr_prf.c:198 witness_warn(2,0,ffffffff83344572) at witness_warn+0x850 witness_debugger sys/kern/subr_witness.c:2576 [inline] witness_warn(2,0,ffffffff83344572) at witness_warn+0x850 sys/kern/subr_witness.c:1485 userret(ffff80002a297730) at userret+0x3a4 sys/kern/kern_sig.c:2227 syscall(ffff800031be8ff0) at syscall+0x9c0 mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff800031be8ff0) at syscall+0x9c0 sys/arch/amd64/amd64/trap.c:600 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf4a7ff5e0d0, count: -6 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800031be8d20 rbx 0xffffffff8382fdd7 cpu_info_full_primary+0x2dd7 rdx 0 rcx 0xffff80002a297730 rax 0xffffffff8382eff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x80834aced26c7964 r11 0x8d06f12c95ef7384 r12 0xffffffff8382fbd8 cpu_info_full_primary+0x2bd8 r13 0 r14 0 r15 0x1 rip 0xffffffff82907a95 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff800031be8d10 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=141253 pid=18844 tcnt=3 stat=onproc flags process=10 proc=4000000 runpri=36, usrpri=86, slppri=36, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a297210,0xffff80002a296030 process=0xffff80003980c9d0 user=0xffff800031be4000, vmspace=0xfffffd806ef1b3c8 estcpu=36, cpticks=4, pctcpu=0.0, user=0, sys=4, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 17890 123902 76318 0 7 0 syz-executor 17890 125655 76318 0 3 0x4000080 kqpoll syz-executor 24172 188892 58690 0 2 0 syz-executor 75926 244377 64693 0 2 0 syz-executor 75926 94827 64693 0 3 0x4000080 fsleep syz-executor 18844 89536 46241 -1 2 0x10 syz-executor *18844 141253 46241 -1 7 0x4000010 syz-executor 18844 417377 46241 -1 3 0x4000010 netlock syz-executor 50417 19011 86025 0 3 0x80 nanoslp syz-executor 50417 449734 86025 0 3 0x4000080 pipewr syz-executor 50417 15638 86025 0 3 0x4000080 fsleep syz-executor 47918 109077 0 0 3 0x14200 acct acct 2641 15989 0 0 3 0x14200 bored sosplice 76318 474500 80849 0 3 0x82 nanoslp syz-executor 69296 149342 80849 0 3 0x82 wait syz-executor 71801 248907 80849 0 3 0x82 nanoslp syz-executor 86025 228355 80849 0 2 0xc82 syz-executor 64693 166329 80849 0 3 0x82 nanoslp syz-executor 58690 323793 80849 0 2 0x2 syz-executor 46241 38562 80849 0 3 0x82 nanoslp syz-executor 46604 371669 80849 0 2 0x2 syz-executor 80849 230487 63154 0 3 0x82 kqread syz-executor 63154 453753 28242 0 3 0x10008a sigsusp ksh 28242 213386 63702 0 3 0x98 kqread sshd-session 63702 187514 4123 0 3 0x92 kqread sshd-session 24396 508045 1 0 3 0x100083 ttyin getty 4123 356854 1 0 3 0x88 kqread sshd 63124 34306 75346 74 3 0x1100092 bpf pflogd 75346 63371 1 0 3 0x80 sbwait pflogd 89559 22684 86476 73 3 0x1100090 kqread syslogd 86476 21952 1 0 3 0x100082 sbwait syslogd 6781 283166 1 0 3 0x100080 kqread resolvd 22977 202823 6673 77 3 0x100092 kqread dhcpleased 85454 214895 6673 77 3 0x100092 kqread dhcpleased 6673 471082 1 0 3 0x80 kqread dhcpleased 84079 166359 0 0 3 0x14200 bored smr 22581 427085 0 0 2 0x14200 zerothread 8738 385588 0 0 3 0x14200 aiodoned aiodoned 18464 424292 0 0 3 0x14200 syncer update 36458 516115 0 0 3 0x14200 cleaner cleaner 45315 210400 0 0 3 0x14200 reaper reaper 23967 212962 0 0 3 0x14200 pgdaemon pagedaemon 97939 212823 0 0 3 0x14200 bored viomb 82795 189424 0 0 3 0x40014200 acpi0 acpi0 40815 229027 0 0 3 0x40014200 idle1 21002 128392 0 0 3 0x14200 bored softnet3 4896 215203 0 0 3 0x14200 bored softnet2 23600 329379 0 0 3 0x14200 bored softnet1 56584 414078 0 0 3 0x14200 bored softnet0 37159 83162 0 0 3 0x14200 bored systqmp 26723 32489 0 0 3 0x14200 bored systq 11588 379876 0 0 3 0x14200 netlock softclockmp 94686 13340 0 0 2 0x40014200 softclock 45625 41555 0 0 3 0x40014200 idle0 1 212727 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 18844 (syz-executor) thread 0xffff80002a297730 (141253) shared rwlock netlock r = 0 (0xffffffff83874a10) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x36e sys/kern/kern_rwlock.c:397 #2 sysctl_file+0x17e6 sys/kern/kern_sysctl.c:1769 #3 kern_sysctl+0x251 sys/kern/kern_sysctl.c:526 #4 sys_sysctl+0x3f2 sys/kern/kern_sysctl.c:-1 #5 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:579 #6 Xsyscall+0x128 Process 11588 (softclockmp) thread 0xffff8000ffffe290 (379876) shared rwlock timeout r = 0 (0xffffffff8384f5e8) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 timeout_run+0x115 sys/kern/kern_timeout.c:690 #2 softclock_thread_run+0xec sys/kern/kern_timeout.c:838 #3 softclock_thread_mp+0x8f sys/kern/kern_timeout.c:873 #4 proc_trampoline+0x10 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10227 11367K 11376K 166960K 11987 0 pcb 18 12K 12K 166960K 61 0 rtable 168 6K 7K 166960K 393 0 pf 36 18K 21K 166960K 81 0 ifaddr 32 4K 7K 166960K 60 0 ifgroup 55 2K 2K 166960K 90 0 sysctl 3 1K 9K 166960K 9 0 counters 68 36K 37K 166960K 96 0 ioctlops 0 0K 4K 166960K 1538 0 iov 0 0K 12K 166960K 16 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1435 90K 91K 166960K 1757 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 5 0 VM map 2 1K 1K 166960K 2 0 sem 10 0K 0K 166960K 13 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 106K 166960K 469 0 sigio 0 0K 0K 166960K 5 0 proc 72 91K 128K 166960K 579 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 33 0 in_multi 64 4K 7K 166960K 119 0 ether_multi 1 0K 0K 166960K 5 0 mrt 2 0K 0K 166960K 4 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 97 440K 440K 166960K 97 0 exec 0 0K 1K 166960K 399 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 247 160K 169K 166960K 5923 0 UVM aobj 10 2K 2K 166960K 10 0 pinsyscall 43 86K 101K 166960K 1540 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 12 0K 1K 166960K 41 0 temp 76 8696K 8768K 166960K 17317 0 kqueue 13 20K 30K 166960K 77 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 26 0 0 1 0 1 1 0 8 0 rtpcb 120 53 0 48 1 0 1 1 0 8 0 rtentry 176 120 0 47 5 0 5 5 0 8 0 unpcb 144 519 0 501 6 0 6 6 0 8 5 syncache 336 3 0 3 1 1 0 1 0 8 0 tcpcb 808 72 0 66 1 0 1 1 0 8 0 arp 128 21 0 9 1 0 1 1 0 8 0 inpcb 328 309 0 298 4 0 4 4 0 8 2 nd6 144 26 0 10 1 0 1 1 0 8 0 pkpcb 40 4 0 4 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 0 1 1 0 8 1 ppxss 1192 9 0 9 1 0 1 1 0 8 1 pppxif 1504 2 0 2 1 0 1 1 0 8 1 pfstscr 40 2 0 1 1 0 1 1 0 8 0 pffrag 232 2 0 0 1 0 1 1 0 482 0 pffrnode 88 2 0 0 1 0 1 1 0 8 0 pffrent 40 4 0 2 1 0 1 1 0 8 0 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfrktable 1344 1 0 1 1 0 1 1 0 8 1 pftag 88 1 0 1 1 0 1 1 0 8 1 pfstitem 24 42 0 0 1 0 1 1 0 8 0 pfstkey 128 44 0 2 2 0 2 2 0 8 0 pfstate 384 42 0 1 5 0 5 5 0 8 0 pfrule 1344 36 0 27 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 475 0 162 29 2 27 29 0 8 3 art_table 32 476 0 162 4 0 4 4 0 8 0 art_node 16 119 0 54 1 0 1 1 0 8 0 sysvmsgpl 40 39 0 35 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 10 0 2 1 0 1 1 0 8 0 shmpl 112 7 0 0 1 0 1 1 0 8 0 dirhash 1024 19 0 2 3 0 3 3 0 8 0 dino2pl 256 2172 0 666 95 0 95 95 0 8 0 ffsino 288 2172 0 666 109 0 109 109 0 8 0 nchpl 144 2802 0 1114 64 0 64 64 0 8 0 uvmvnodes 80 2542 0 0 52 0 52 52 0 8 0 vnodes 216 2542 0 0 142 0 142 142 0 8 0 namei 1024 8985 0 8985 2 1 1 2 0 8 1 percpumem 16 63 0 14 1 0 1 1 0 8 0 kstatmem 264 50 0 22 3 0 3 3 0 8 1 scsiplug 72 2 0 2 1 0 1 1 0 8 1 scxspl 216 9067 0 9067 10 2 8 8 1 8 8 plimitpl 152 59 0 42 1 0 1 1 0 8 0 sigapl 424 762 0 710 7 1 6 7 0 8 0 knotepl 120 522 0 0 16 0 16 16 0 8 0 kqueuepl 224 173 0 163 5 4 1 5 0 8 0 pipepl 336 196 0 168 8 0 8 8 0 8 5 fdescpl 520 742 0 710 3 0 3 3 0 8 0 filepl 160 3872 0 3648 16 0 16 16 0 8 5 lockfpl 104 94 0 92 1 0 1 1 0 8 0 lockfspl 48 44 0 42 1 0 1 1 0 8 0 sessionpl 144 22 0 13 1 0 1 1 0 8 0 pgrppl 48 33 0 16 1 0 1 1 0 8 0 ucredpl 104 329 0 313 1 0 1 1 0 8 0 zombiepl 144 713 0 710 1 0 1 1 0 8 0 processpl 1240 762 0 710 5 0 5 5 0 8 0 procpl 656 1325 0 1267 6 0 6 6 0 8 0 srpgc 96 6 0 6 1 0 1 1 0 8 1 sosppl 168 1 0 1 1 0 1 1 0 8 1 sockpl 728 902 0 866 21 9 12 16 0 8 8 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 107 0 0 14 0 14 14 0 8 0 mcl2k 2048 78 0 0 10 0 10 10 0 8 0 mtagpl 96 110 0 0 3 0 3 3 0 8 0 mbufpl 256 1244 0 0 78 0 78 78 0 8 0 bufpl 280 2932 0 126 201 0 201 201 0 8 0 anonpl 32 7630 0 0 62 0 62 62 0 246 0 amapchunkpl 152 18344 0 17831 27 0 27 27 0 158 6 amappl16 200 2613 0 2581 18 3 15 15 0 8 12 amappl15 192 5 0 5 1 1 0 1 0 8 0 amappl14 184 114 0 102 1 0 1 1 0 8 0 amappl13 176 9 0 9 1 1 0 1 0 8 0 amappl12 168 1375 0 1344 4 1 3 3 0 8 0 amappl11 160 53 0 39 1 0 1 1 0 8 0 amappl10 152 50 0 50 1 1 0 1 0 8 0 amappl9 144 251 0 251 1 1 0 1 0 8 0 amappl8 136 21 0 19 1 0 1 1 0 8 0 amappl7 128 115 0 103 1 0 1 1 0 8 0 amappl6 120 176 0 173 1 0 1 1 0 8 0 amappl5 112 124 0 113 1 0 1 1 0 8 0 amappl4 104 309 0 289 1 0 1 1 0 8 0 amappl3 96 3463 0 3345 4 0 4 4 0 8 0 amappl2 88 638 0 576 2 0 2 2 0 8 0 amappl1 80 9416 0 8807 15 1 14 15 0 8 1 amappl 88 5209 0 5037 5 0 5 5 0 92 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 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 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 9 0 0 1 0 1 1 0 8 0 uaddrrnd 24 742 0 710 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 742 0 710 1 0 1 1 0 8 0 vmmpekpl 168 7760 0 7718 3 0 3 3 0 8 0 vmmpepl 168 52618 0 50578 101 0 101 101 0 357 9 vmsppl 480 741 0 710 5 1 4 5 0 8 0 rwobjpl 72 18885 0 15384 66 0 66 66 0 8 2 pdppl 4096 1491 0 1420 95 24 71 83 0 8 0 pvpl 32 15196 0 0 123 0 123 123 0 265 0 pmappl 256 741 0 710 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 456 0 30 13 0 13 13 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8338bf48) at panic+0x1e5 sys/kern/subr_prf.c:198 witness_warn(2,0,ffffffff83344572) at witness_warn+0x850 witness_debugger sys/kern/subr_witness.c:2576 [inline] witness_warn(2,0,ffffffff83344572) at witness_warn+0x850 sys/kern/subr_witness.c:1485 userret(ffff80002a297730) at userret+0x3a4 sys/kern/kern_sig.c:2227 syscall(ffff800031be8ff0) at syscall+0x9c0 mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff800031be8ff0) at syscall+0x9c0 sys/arch/amd64/amd64/trap.c:600 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf4a7ff5e0d0, count: -6 ddb{0}> machine ddbcpu 1