panic() at panic+0x147 fifo_badop(ffffffff81a96ac2) at fifo_badop+0x12 VOP_STRATEGY(ffffff006bbcec00) at VOP_STRATEGY+0x6b bwrite(ffff800021172a60) at bwrite+0x195 VOP_BWRITE(ffffff006bbd74b8) at VOP_BWRITE+0x47 ufs_mkdir(ffffffff81dfb828) at ufs_mkdir+0x5a9 VOP_MKDIR(ffff8000ffffc710,1ed,ffffff9c,ffff800021172a18) at VOP_MKDIR+0x65 domkdirat(ffff800021172c50,ffff8000ffffc710,ffff8000210a6300,880) at domkdirat+0x10f syscall(0) at syscall+0x3e4 Xsyscall(6,88,7f7ffffc3180,88,0,7f7ffffc31c0) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc31f0, 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> show panic fifo_badop called ddb> trace db_enter() at db_enter+0xa panic() at panic+0x147 fifo_badop(ffffffff81a96ac2) at fifo_badop+0x12 VOP_STRATEGY(ffffff006bbcec00) at VOP_STRATEGY+0x6b bwrite(ffff800021172a60) at bwrite+0x195 VOP_BWRITE(ffffff006bbd74b8) at VOP_BWRITE+0x47 ufs_mkdir(ffffffff81dfb828) at ufs_mkdir+0x5a9 VOP_MKDIR(ffff8000ffffc710,1ed,ffffff9c,ffff800021172a18) at VOP_MKDIR+0x65 domkdirat(ffff800021172c50,ffff8000ffffc710,ffff8000210a6300,880) at domkdirat+0x10f syscall(0) at syscall+0x3e4 Xsyscall(6,88,7f7ffffc3180,88,0,7f7ffffc31c0) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc31f0, count: -11 ddb> show registers rdi 0xffffffff81e10dd8 kprintf_mutex rsi 0x5 rbp 0xffff8000211726a0 rbx 0xffff800021172740 rdx 0x3fd rcx 0 rax 0 r8 0xffff800021172670 r9 0 r10 0xffff8000211724d8 r11 0x8 r12 0x3000000008 r13 0xffff8000211726b0 r14 0x100 r15 0xffffffff81c2df44 apollo_pio_rec+0x556 rip 0xffffffff81679b8a db_enter+0xa cs 0x8 rflags 0x246 rsp 0xffff8000211726a0 ss 0x10 db_enter+0xa: popq %rbp ddb> show proc PROC (syz-executor0) pid=153139 stat=onproc flags process=2 proc=0 pri=17, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff8000210c3c30,0xffffffff81eafaa0 process=0xffff8000210a6300 user=0xffff80002116d000, vmspace=0xffffff007f12b000 estcpu=36, cpticks=4, pctcpu=0.0 user=0, sys=4, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND * 8096 153139 84940 0 7 0x2 syz-executor0 99563 489020 84940 0 2 0x2 syz-executor1 84940 117178 22849 0 3 0x82 thrsleep syz-fuzzer 84940 371253 22849 0 2 0x4000482 syz-fuzzer 84940 439125 22849 0 3 0x4000082 thrsleep syz-fuzzer 84940 285210 22849 0 3 0x4000082 thrsleep syz-fuzzer 84940 371158 22849 0 3 0x4000082 thrsleep syz-fuzzer 84940 502600 22849 0 3 0x4000082 thrsleep syz-fuzzer 84940 129310 22849 0 3 0x4000082 thrsleep syz-fuzzer 84940 45068 22849 0 3 0x4000082 kqread syz-fuzzer 22849 1600 48987 0 3 0x10008a pause ksh 48987 493243 89221 0 3 0x92 select sshd 94666 426738 1 0 3 0x100083 ttyin getty 89221 438317 1 0 3 0x80 select sshd 47455 94048 60265 73 3 0x100090 kqread syslogd 60265 98474 1 0 3 0x100082 netio syslogd 54853 277976 1 77 3 0x100090 poll dhclient 66341 438800 1 0 3 0x80 poll dhclient 53912 91316 0 0 3 0x14200 pgzero zerothread 21310 310596 0 0 3 0x14200 aiodoned aiodoned 33096 523853 0 0 3 0x14200 syncer update 38165 279794 0 0 3 0x14200 cleaner cleaner 71425 214796 0 0 3 0x14200 reaper reaper 7995 26751 0 0 3 0x14200 pgdaemon pagedaemon 29088 388297 0 0 3 0x14200 bored crynlk 47936 106792 0 0 3 0x14200 bored crypto 52764 199078 0 0 3 0x40014200 acpi0 acpi0 98025 396262 0 0 3 0x14200 bored softnet 45792 67653 0 0 3 0x14200 bored systqmp 49044 254687 0 0 3 0x14200 bored systq 1403 317366 0 0 3 0x40014200 bored softclock 22971 445326 0 0 3 0x40014200 idle0 1 214682 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper