panic: vput: v_writecount != 0 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:212 vput(fffffd8035d7f2e0) at vput+0x187 sys/kern/vfs_subr.c:759 vn_closefile(fffffd802af10f00,ffff800014fdf160) at vn_closefile+0x15b sys/kern/vfs_vnops.c:589 fdrop(fffffd802af10f00,ffff800014fdf160) at fdrop+0xc9 sys/kern/kern_descrip.c:1269 closef(fffffd802af10f00,ffff800014fdf160) at closef+0x118 sys/kern/kern_descrip.c:1253 fdfree(ffff800014fdf160) at fdfree+0xf7 sys/kern/kern_descrip.c:1185 exit1(ffff800014fdf160,0,1) at exit1+0x32f sys/kern/kern_exit.c:196 sys_exit(ffff800014fdf160,ffff800015a06490,ffff800015a06500) at sys_exit+0x17 sys/kern/kern_exit.c:94 syscall(ffff800015a06560) at syscall+0x508 Xsyscall(0,1,0,1,0,7f7ffffcc384) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffcc350, count: 4 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 vput: v_writecount != 0 ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:212 vput(fffffd8035d7f2e0) at vput+0x187 sys/kern/vfs_subr.c:759 vn_closefile(fffffd802af10f00,ffff800014fdf160) at vn_closefile+0x15b sys/kern/vfs_vnops.c:589 fdrop(fffffd802af10f00,ffff800014fdf160) at fdrop+0xc9 sys/kern/kern_descrip.c:1269 closef(fffffd802af10f00,ffff800014fdf160) at closef+0x118 sys/kern/kern_descrip.c:1253 fdfree(ffff800014fdf160) at fdfree+0xf7 sys/kern/kern_descrip.c:1185 exit1(ffff800014fdf160,0,1) at exit1+0x32f sys/kern/kern_exit.c:196 sys_exit(ffff800014fdf160,ffff800015a06490,ffff800015a06500) at sys_exit+0x17 sys/kern/kern_exit.c:94 syscall(ffff800015a06560) at syscall+0x508 Xsyscall(0,1,0,1,0,7f7ffffcc384) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffcc350, count: -11 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800015a06180 rbx 0xffff800015a06230 rdx 0x2 rcx 0 rax 0 r8 0xffff800015a06140 r9 0x1 r10 0 r11 0x9434756d3625d550 r12 0x3000000008 r13 0xffff800015a06190 r14 0x100 r15 0x1 rip 0xffffffff8125b5f8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800015a06170 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.0) pid=326610 stat=onproc flags process=1008 proc=2000 pri=32, usrpri=71, nice=20 forw=0xffffffffffffffff, list=0xffff800014fde018,0xffffffff822c3340 process=0xffff8000ffff6a30 user=0xffff800015a01000, vmspace=0xfffffd803f014cc0 estcpu=21, cpticks=2, pctcpu=0.10 user=0, sys=2, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 90070 406631 1 0 3 0x100083 ttyin getty 66235 272344 0 0 3 0x14200 bored sosplice 18893 387885 44669 0 3 0x82 wait syz-executor.0 50824 263280 44669 0 3 0x82 piperd syz-executor.1 44669 92246 15551 0 3 0x82 kqread syz-fuzzer 44669 348364 15551 0 3 0x4000082 thrsleep syz-fuzzer 44669 64781 15551 0 3 0x4000082 thrsleep syz-fuzzer 44669 469277 15551 0 3 0x4000082 thrsleep syz-fuzzer 44669 236731 15551 0 3 0x4000082 thrsleep syz-fuzzer 44669 297065 15551 0 3 0x4000082 thrsleep syz-fuzzer 44669 512336 15551 0 3 0x4000082 thrsleep syz-fuzzer 15551 54636 79452 0 3 0x10008a pause ksh 79452 481500 9249 0 3 0x92 select sshd 9249 290630 1 0 3 0x80 select sshd 1056 345654 8182 73 2 0x100090 syslogd 8182 47832 1 0 3 0x100082 netio syslogd 93748 147913 1 77 3 0x100090 poll dhclient 44234 466627 1 0 3 0x80 poll dhclient 17617 1158 0 0 2 0x14200 zerothread 97654 91882 0 0 3 0x14200 aiodoned aiodoned 33597 437371 0 0 3 0x14200 syncer update 77223 42740 0 0 3 0x14200 cleaner cleaner 66288 221913 0 0 3 0x14200 reaper reaper 58260 161045 0 0 3 0x14200 pgdaemon pagedaemon 73536 159209 0 0 3 0x14200 bored crynlk 82429 69347 0 0 3 0x14200 bored crypto 68113 30928 0 0 3 0x40014200 acpi0 acpi0 31104 256916 0 0 3 0x14200 bored softnet 25544 86460 0 0 3 0x14200 bored systqmp 12487 196497 0 0 3 0x14200 bored systq 5967 377896 0 0 3 0x40014200 bored softclock 52750 375414 0 0 3 0x40014200 idle0 66373 161625 0 0 3 0x14200 bored smr 1 508272 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 Kern Lim devbuf 9521 6369K 10781K 78643K 18579 0 0 pcb 13 8K 8K 78643K 244 0 0 rtable 116 4K 4K 78643K 675 0 0 ifaddr 60 14K 15K 78643K 301 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 162 0 0 iov 0 0K 28K 78643K 384 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1208 76K 77K 78643K 4035 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 44 0 0 VM map 2 0K 0K 78643K 2 0 0 sem 12 0K 0K 78643K 271 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 3080 0 0 sigio 1 0K 0K 78643K 47 0 0 proc 42 30K 54K 78643K 638 0 0 subproc 32 2K 2K 78643K 36 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 279 0 0 in_multi 33 2K 2K 78643K 122 0 0 ether_multi 1 0K 0K 78643K 13 0 0 mrt 0 0K 0K 78643K 7 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 84 371K 371K 78643K 84 0 0 exec 0 0K 1K 78643K 432 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 91 20K 36K 78643K 8162 0 0 UVM aobj 130 4K 4K 78643K 145 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 1K 78643K 125 0 0 NDP 13 0K 0K 78643K 81 0 0 temp 178 2727K 2855K 78643K 12607 0 0 kqueue 0 0K 0K 78643K 25 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 6 0 0 1 0 1 1 0 8 0 rtpcb 80 134 0 132 1 0 1 1 0 8 0 rtentry 112 49 0 5 2 0 2 2 0 8 0 unpcb 120 1149 0 1141 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 386 0 386 1 1 0 1 0 8 0 tcpcb 544 479 0 475 1 0 1 1 0 8 0 inpcb 280 1288 0 1281 2 1 1 2 0 8 0 nd6 48 6 0 0 1 0 1 1 0 8 0 pkpcb 40 12 0 12 5 5 0 1 0 8 0 ppxss 1128 49 0 49 13 13 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 188 0 0 12 0 12 12 0 8 0 art_table 32 189 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 sysvmsgpl 40 19 0 8 1 0 1 1 0 8 0 semapl 112 269 0 259 1 0 1 1 0 8 0 shmpl 112 143 0 15 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 6476 0 5069 46 0 46 46 0 8 0 ffsino 240 6476 0 5069 84 0 84 84 0 8 0 nchpl 144 11014 0 9379 61 0 61 61 0 8 0 uvmvnodes 72 5934 0 0 108 0 108 108 0 8 0 vnodes 200 5934 0 0 313 0 313 313 0 8 0 namei 1024 34557 0 34557 1 0 1 1 0 8 1 scsiplug 64 6 0 6 6 5 1 1 0 8 1 scxspl 192 51958 0 51958 10 9 1 5 0 8 1 plimitpl 152 261 0 254 1 0 1 1 0 8 0 sigapl 432 3256 0 3243 2 0 2 2 0 8 0 futexpl 56 51065 0 51065 1 0 1 1 0 8 1 knotepl 112 684 0 665 1 0 1 1 0 8 0 kqueuepl 104 824 0 822 1 0 1 1 0 8 0 pipepl 112 1868 0 1849 6 5 1 2 0 8 0 fdescpl 424 3257 0 3243 2 0 2 2 0 8 0 filepl 120 19758 0 19662 5 1 4 5 0 8 0 lockfpl 104 1045 0 1045 4 3 1 1 0 8 1 lockfspl 48 355 0 355 4 3 1 1 0 8 1 sessionpl 112 22 0 12 1 0 1 1 0 8 0 pgrppl 48 52 0 42 1 0 1 1 0 8 0 ucredpl 96 4190 0 4183 1 0 1 1 0 8 0 zombiepl 144 3244 0 3243 2 1 1 1 0 8 0 processpl 864 3272 0 3243 4 0 4 4 0 8 0 procpl 632 7320 0 7285 4 0 4 4 0 8 0 sosppl 128 37 0 37 11 11 0 1 0 8 0 sockpl 384 2617 0 2600 4 1 3 3 0 8 1 mcl64k 65536 621 0 621 73 73 0 65 0 8 0 mcl16k 16384 14 0 14 10 10 0 1 0 8 0 mcl12k 12288 53 0 53 10 9 1 1 0 8 1 mcl9k 9216 38 0 38 12 12 0 1 0 8 0 mcl8k 8192 40 0 40 11 10 1 1 0 8 1 mcl4k 4096 149 0 149 4 3 1 1 0 8 1 mcl2k2 2112 18 0 18 7 6 1 1 0 8 1 mcl2k 2048 57690 0 57653 14 8 6 12 0 8 0 mtagpl 80 14 0 5 2 1 1 1 0 8 0 mbufpl 256 105891 0 105807 40 32 8 37 0 8 0 bufpl 256 23321 0 14625 862 0 862 862 0 8 315 anonpl 16 311053 0 295627 162 100 62 64 0 62 0 amapchunkpl 152 14295 0 14166 48 40 8 18 0 158 3 amappl16 192 18187 0 17326 148 104 44 44 0 8 0 amappl15 184 1525 0 1523 1 0 1 1 0 8 0 amappl14 176 53 0 48 1 0 1 1 0 8 0 amappl13 168 9 0 8 1 0 1 1 0 8 0 amappl12 160 13 0 11 1 0 1 1 0 8 0 amappl11 152 1581 0 1569 1 0 1 1 0 8 0 amappl10 144 66 0 66 5 5 0 1 0 8 0 amappl9 136 559 0 556 1 0 1 1 0 8 0 amappl8 128 133 0 115 1 0 1 1 0 8 0 amappl7 120 38 0 34 1 0 1 1 0 8 0 amappl6 112 1576 0 1569 1 0 1 1 0 8 0 amappl5 104 158 0 148 1 0 1 1 0 8 0 amappl4 96 3521 0 3495 1 0 1 1 0 8 0 amappl3 88 256 0 246 1 0 1 1 0 8 0 amappl2 80 26824 0 26759 4 2 2 3 0 8 0 amappl1 72 64563 0 64130 26 17 9 19 0 8 0 amappl 80 7585 0 7544 1 0 1 1 0 84 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma64 64 259 0 259 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 144 0 15 3 0 3 3 0 8 0 uaddrrnd 24 3257 0 3243 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3257 0 3243 1 0 1 1 0 8 0 vmmpekpl 168 21421 0 21397 2 0 2 2 0 8 0 vmmpepl 168 385246 0 383319 180 96 84 91 0 357 0 vmsppl 272 3256 0 3243 2 1 1 2 0 8 0 pdppl 4096 6520 0 6486 6 1 5 6 0 8 0 pvpl 32 856481 0 837493 323 159 164 222 0 265 10 pmappl 200 3256 0 3243 1 0 1 1 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 1126 0 140 31 2 29 29 0 8 0