panic: rw_enter: dklk locking against myself Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *496692 30620 0 0 0x4000000 0 syz-executor.1 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82474a14) at panic+0x161 sys/kern/subr_prf.c:202 rw_enter(ffff8000006aa058,11) at rw_enter+0x36f sys/kern/kern_rwlock.c:174 vndopen(2902,3,2000,ffff800021674fc0) at vndopen+0x8d sys/dev/vnd.c:185 spec_open(ffff800024717668) at spec_open+0x3c8 sys/kern/spec_vnops.c:157 VOP_OPEN(fffffd8075e9c4c8,3,fffffd807f7d7720,ffff800021674fc0) at VOP_OPEN+0x73 sys/kern/vfs_vops.c:153 vn_open(ffff800024717900,3,0) at vn_open+0x467 sys/kern/vfs_vnops.c:183 vndioctl(2902,c0384600,ffff800024717c20,1,ffff800021674fc0) at vndioctl+0xa07 sys/dev/vnd.c:452 VOP_IOCTL(fffffd8075e9c4c8,c0384600,ffff800024717c20,1,fffffd807f7d7720,ffff800021674fc0) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:295 vn_ioctl(fffffd806af14540,c0384600,ffff800024717c20,ffff800021674fc0) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531 sys_ioctl(ffff800021674fc0,ffff800024717d38,ffff800024717d90) at sys_ioctl+0x49e syscall(ffff800024717e00) at syscall+0x571 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x70fdd4bc920, count: 2 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: rw_enter: dklk locking against myself ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82474a14) at panic+0x161 sys/kern/subr_prf.c:202 rw_enter(ffff8000006aa058,11) at rw_enter+0x36f sys/kern/kern_rwlock.c:174 vndopen(2902,3,2000,ffff800021674fc0) at vndopen+0x8d sys/dev/vnd.c:185 spec_open(ffff800024717668) at spec_open+0x3c8 sys/kern/spec_vnops.c:157 VOP_OPEN(fffffd8075e9c4c8,3,fffffd807f7d7720,ffff800021674fc0) at VOP_OPEN+0x73 sys/kern/vfs_vops.c:153 vn_open(ffff800024717900,3,0) at vn_open+0x467 sys/kern/vfs_vnops.c:183 vndioctl(2902,c0384600,ffff800024717c20,1,ffff800021674fc0) at vndioctl+0xa07 sys/dev/vnd.c:452 VOP_IOCTL(fffffd8075e9c4c8,c0384600,ffff800024717c20,1,fffffd807f7d7720,ffff800021674fc0) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:295 vn_ioctl(fffffd806af14540,c0384600,ffff800024717c20,ffff800021674fc0) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531 sys_ioctl(ffff800021674fc0,ffff800024717d38,ffff800024717d90) at sys_ioctl+0x49e syscall(ffff800024717e00) at syscall+0x571 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x70fdd4bc920, count: -13 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800024717430 rbx 0x4 rdx 0x8b rcx 0x2 rax 0x2d r8 0xffffffff81b21fc5 kprintf+0x145 r9 0x1 r10 0xe517ec2dc8bbda3b r11 0xa42f4745caf1d4e r12 0 r13 0xffff800021674fc4 r14 0 r15 0x1 rip 0xffffffff8102d098 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800024717420 ss 0 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.1) pid=496692 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=81, nice=20 forw=0xffffffffffffffff, list=0xffff800021674000,0xffffffff828ac128 process=0xffff8000216533b8 user=0xffff800024712000, vmspace=0xfffffd807f00a000 estcpu=31, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 30620 267524 22237 0 2 0 syz-executor.1 30620 349953 22237 0 2 0x4000000 syz-executor.1 *30620 496692 22237 0 7 0x4000000 syz-executor.1 13494 393419 21970 0 2 0x2 syz-executor.0 22237 67114 21970 0 3 0x82 nanoslp syz-executor.1 21970 398865 18807 0 3 0x82 kqread syz-fuzzer 21970 157150 18807 0 3 0x4000082 thrsleep syz-fuzzer 21970 421838 18807 0 3 0x4000082 thrsleep syz-fuzzer 21970 378457 18807 0 3 0x4000082 thrsleep syz-fuzzer 21970 405843 18807 0 3 0x4000082 thrsleep syz-fuzzer 21970 122317 18807 0 3 0x4000082 thrsleep syz-fuzzer 18807 415738 45193 0 3 0x10008a sigsusp ksh 45193 139547 76718 0 3 0x9a select sshd 72891 116013 1 0 3 0x100083 ttyin getty 76718 384458 1 0 3 0x88 select sshd 49333 448021 81092 73 3 0x100090 kqread syslogd 81092 69875 1 0 3 0x100082 netio syslogd 90581 494319 1 0 3 0x100080 kqread resolvd 68243 62328 52509 77 3 0x100092 kqread dhcpleased 7605 452638 52509 77 3 0x100092 kqread dhcpleased 52509 175039 1 0 3 0x80 kqread dhcpleased 12159 249068 0 0 3 0x14200 bored smr 3369 14558 0 0 2 0x14200 zerothread 62059 217251 0 0 3 0x14200 aiodoned aiodoned 24713 96122 0 0 3 0x14200 syncer update 27316 489013 0 0 3 0x14200 cleaner cleaner 64389 296596 0 0 3 0x14200 reaper reaper 79174 19933 0 0 3 0x14200 pgdaemon pagedaemon 99614 470303 0 0 3 0x14200 bored crynlk 84824 143445 0 0 3 0x14200 bored crypto 62722 458494 0 0 3 0x14200 bored viomb 30061 85269 0 0 3 0x40014200 acpi0 acpi0 15370 270229 0 0 3 0x14200 bored softnet 73653 322876 0 0 3 0x14200 bored systqmp 7744 352484 0 0 3 0x14200 bored systq 51069 454279 0 0 3 0x40014200 bored softclock 31451 409394 0 0 3 0x40014200 idle0 1 402033 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 10103 6355K 6492K 78643K 13075 0 pcb 13 8K 8K 78643K 95 0 rtable 106 3K 3K 78643K 174 0 ifaddr 39 10K 10K 78643K 39 0 counters 21 16K 16K 78643K 21 0 ioctlops 0 0K 2K 78643K 2642 0 iov 0 0K 8K 78643K 1013 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1219 77K 77K 78643K 1890 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 63 0 VM map 2 0K 0K 78643K 2 0 sem 12 0K 0K 78643K 110 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 5 13K 25K 78643K 15295 0 sigio 0 0K 0K 78643K 139 0 proc 56 54K 71K 78643K 279 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 26 0 in_multi 33 2K 2K 78643K 33 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 37 175K 175K 78643K 37 0 exec 0 0K 2K 78643K 378 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 190 24K 24K 78643K 179306 0 UVM aobj 131 4K 4K 78643K 223 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 5 0K 0K 78643K 9 0 temp 101 4205K 4269K 78643K 33403 0 kqueue 10 14K 14K 78643K 10 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 24 0 21 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 10583 0 10570 2 1 1 2 0 8 0 syncache 296 4 0 4 1 1 0 1 0 8 0 tcpcb 736 78 0 74 3 2 1 3 0 8 0 arp 88 6 0 0 1 0 1 1 0 8 0 inpcb 304 384 0 377 1 0 1 1 0 8 0 nd6 48 6 0 0 1 0 1 1 0 8 0 kcovpl 48 2 0 0 1 0 1 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 semapl 112 108 0 98 1 0 1 1 0 8 0 shmpl 112 220 0 92 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 16830 0 15426 88 0 88 88 0 8 0 ffsino 240 16830 0 15426 83 0 83 83 0 8 0 nchpl 144 35057 0 33443 60 0 60 60 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 224 5926 0 0 349 0 349 349 0 8 0 namei 1024 88628 0 88627 1 0 1 1 0 8 0 scxspl 216 97042 0 97042 14 13 1 8 0 8 1 plimitpl 152 16 0 8 1 0 1 1 0 8 0 sigapl 424 15525 0 15494 4 0 4 4 0 8 0 futexpl 56 83606 0 83606 2 1 1 1 0 8 1 knotepl 112 178 0 140 2 0 2 2 0 8 0 kqueuepl 184 428 0 422 1 0 1 1 0 8 0 pipepl 304 2095 0 2085 9 8 1 2 0 8 0 fdescpl 432 15510 0 15494 3 1 2 3 0 8 0 filepl 120 52776 0 52668 5 1 4 5 0 8 0 lockfpl 104 1847 0 1845 1 0 1 1 0 8 0 lockfspl 48 824 0 822 1 0 1 1 0 8 0 sessionpl 144 17 0 7 1 0 1 1 0 8 0 pgrppl 48 275 0 265 1 0 1 1 0 8 0 ucredpl 96 1398 0 1388 1 0 1 1 0 8 0 zombiepl 144 15494 0 15494 14 13 1 1 0 8 1 processpl 1008 15525 0 15494 11 6 5 5 0 8 0 procpl 672 31206 0 31168 4 0 4 4 0 8 0 sockpl 448 10991 0 10968 26 23 3 5 0 8 0 mcl64k 65536 280 0 280 13 12 1 1 0 8 1 mcl16k 16384 114 0 114 9 8 1 1 0 8 1 mcl12k 12288 299 0 299 25 25 0 1 0 8 0 mcl9k 9216 194 0 194 23 23 0 1 0 8 0 mcl8k 8192 769 0 769 13 12 1 1 0 8 1 mcl4k 4096 957 0 957 35 35 0 1 0 8 0 mcl2k2 2112 105 0 105 7 7 0 1 0 8 0 mcl2k 2048 29471 0 29439 18 12 6 6 0 8 1 mtagpl 96 3 0 3 1 1 0 1 0 8 0 mbufpl 256 126141 0 126028 21 11 10 11 0 8 1 bufpl 280 18757 0 12351 458 0 458 458 0 8 0 anonpl 24 3801092 0 3795138 50 11 39 40 0 188 1 amapchunkpl 152 422966 0 422635 37 23 14 15 0 158 0 amappl16 200 29116 0 28959 9 0 9 9 0 8 0 amappl15 192 1 0 0 1 0 1 1 0 8 0 amappl13 176 28 0 26 1 0 1 1 0 8 0 amappl12 168 7648 0 7644 1 0 1 1 0 8 0 amappl11 160 7679 0 7668 1 0 1 1 0 8 0 amappl10 152 30 0 25 1 0 1 1 0 8 0 amappl9 144 227 0 224 1 0 1 1 0 8 0 amappl8 136 485 0 427 3 0 3 3 0 8 0 amappl7 128 64 0 53 1 0 1 1 0 8 0 amappl6 120 112 0 102 1 0 1 1 0 8 0 amappl5 112 8102 0 8087 1 0 1 1 0 8 0 amappl4 104 15927 0 15903 1 0 1 1 0 8 0 amappl3 96 8220 0 8217 1 0 1 1 0 8 0 amappl2 88 976 0 924 2 0 2 2 0 8 0 amappl1 80 256536 0 256124 12 3 9 12 0 8 0 amappl 88 178975 0 178864 3 0 3 3 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 64 222 0 92 3 0 3 3 0 8 0 uaddrrnd 24 15510 0 15494 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 15510 0 15494 1 0 1 1 0 8 0 vmmpekpl 168 76116 0 76095 2 0 2 2 0 8 0 vmmpepl 168 1686370 0 1684994 100 35 65 65 0 357 3 vmsppl 272 15509 0 15494 3 1 2 2 0 8 1 rwobjpl 24 278241 0 277397 10 4 6 6 0 8 0 pdppl 4096 31027 0 30988 75 34 41 45 0 8 2 pvpl 32 6161737 0 6152475 231 152 79 132 0 265 2 pmappl 192 15509 0 15494 1 0 1 1 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 407 0 152 8 0 8 8 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82474a14) at panic+0x161 sys/kern/subr_prf.c:202 rw_enter(ffff8000006aa058,11) at rw_enter+0x36f sys/kern/kern_rwlock.c:174 vndopen(2902,3,2000,ffff800021674fc0) at vndopen+0x8d sys/dev/vnd.c:185 spec_open(ffff800024717668) at spec_open+0x3c8 sys/kern/spec_vnops.c:157 VOP_OPEN(fffffd8075e9c4c8,3,fffffd807f7d7720,ffff800021674fc0) at VOP_OPEN+0x73 sys/kern/vfs_vops.c:153 vn_open(ffff800024717900,3,0) at vn_open+0x467 sys/kern/vfs_vnops.c:183 vndioctl(2902,c0384600,ffff800024717c20,1,ffff800021674fc0) at vndioctl+0xa07 sys/dev/vnd.c:452 VOP_IOCTL(fffffd8075e9c4c8,c0384600,ffff800024717c20,1,fffffd807f7d7720,ffff800021674fc0) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:295 vn_ioctl(fffffd806af14540,c0384600,ffff800024717c20,ffff800021674fc0) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531 sys_ioctl(ffff800021674fc0,ffff800024717d38,ffff800024717d90) at sys_ioctl+0x49e syscall(ffff800024717e00) at syscall+0x571 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x70fdd4bc920, count: -13 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82474a14) at panic+0x161 sys/kern/subr_prf.c:202 rw_enter(ffff8000006aa058,11) at rw_enter+0x36f sys/kern/kern_rwlock.c:174 vndopen(2902,3,2000,ffff800021674fc0) at vndopen+0x8d sys/dev/vnd.c:185 spec_open(ffff800024717668) at spec_open+0x3c8 sys/kern/spec_vnops.c:157 VOP_OPEN(fffffd8075e9c4c8,3,fffffd807f7d7720,ffff800021674fc0) at VOP_OPEN+0x73 sys/kern/vfs_vops.c:153 vn_open(ffff800024717900,3,0) at vn_open+0x467 sys/kern/vfs_vnops.c:183 vndioctl(2902,c0384600,ffff800024717c20,1,ffff800021674fc0) at vndioctl+0xa07 sys/dev/vnd.c:452 VOP_IOCTL(fffffd8075e9c4c8,c0384600,ffff800024717c20,1,fffffd807f7d7720,ffff800021674fc0) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:295 vn_ioctl(fffffd806af14540,c0384600,ffff800024717c20,ffff800021674fc0) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531 sys_ioctl(ffff800021674fc0,ffff800024717d38,ffff800024717d90) at sys_ioctl+0x49e syscall(ffff800024717e00) at syscall+0x571 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x70fdd4bc920, count: -13