panic: witness_warn Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *406261 83548 32767 0x1010 0x4080000 1 syz-executor0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x16c sys/kern/subr_prf.c:208 witness_warn(ea37504bd14f1bd3,0,ffff800020bba4c8) at witness_warn+0x6e0 witness_debugger sys/kern/subr_witness.c:2546 [inline] witness_warn(ea37504bd14f1bd3,0,ffff800020bba4c8) at witness_warn+0x6e0 sys/kern/subr_witness.c:1462 userret(1db18f455523ed19) at userret+0x361 sys/kern/kern_sig.c:1899 syscall(541e68d93654cbdd) at syscall+0x680 mi_syscall_return sys/sys/syscall_mi.h:122 [inline] syscall(541e68d93654cbdd) at syscall+0x680 sys/arch/amd64/amd64/trap.c:605 Xsyscall(6,5,c,0,3,a07008670d8) at Xsyscall+0x128 end of kernel end trace frame: 0xa098365b230, 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{1}> ddb{1}> set $lines = 0 ddb{1}> show panic witness_warn ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x16c sys/kern/subr_prf.c:208 witness_warn(ea37504bd14f1bd3,0,ffff800020bba4c8) at witness_warn+0x6e0 witness_debugger sys/kern/subr_witness.c:2546 [inline] witness_warn(ea37504bd14f1bd3,0,ffff800020bba4c8) at witness_warn+0x6e0 sys/kern/subr_witness.c:1462 userret(1db18f455523ed19) at userret+0x361 sys/kern/kern_sig.c:1899 syscall(541e68d93654cbdd) at syscall+0x680 mi_syscall_return sys/sys/syscall_mi.h:122 [inline] syscall(541e68d93654cbdd) at syscall+0x680 sys/arch/amd64/amd64/trap.c:605 Xsyscall(6,5,c,0,3,a07008670d8) at Xsyscall+0x128 end of kernel end trace frame: 0xa098365b230, count: -6 ddb{1}> show registers rdi 0xffffffff81107617 db_enter+0x17 rsi 0x4745 __ALIGN_SIZE+0x3745 rbp 0xffff800020c7fb70 rbx 0xffff800020c7fc10 rdx 0x4746 __ALIGN_SIZE+0x3746 rcx 0xffff800000b46000 rax 0xffff800000b46000 r8 0xffffffff81788154 kprintf+0x174 r9 0x1 r10 0x263be4e83557ba98 r11 0x432b544e619eff4e r12 0x3000000008 r13 0xffff800020c7fb80 r14 0x100 r15 0x1 rip 0xffffffff81107618 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020c7fb60 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor0) pid=406261 stat=onproc flags process=1010 proc=4080000 pri=32, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020bbabd0,0xffff800020bbb2e8 process=0xffff800020bcad38 user=0xffff800020c7a000, vmspace=0xfffffd807f00c870 estcpu=36, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 74591 399371 38596 32767 3 0x90 nanosleep syz-executor1 74591 88995 38596 32767 3 0x4000090 nanosleep syz-executor1 83548 470034 58256 32767 3 0x3010 suspend syz-executor0 83548 279091 58256 32767 2 0x4081010 syz-executor0 *83548 406261 58256 32767 7 0x4081010 syz-executor0 83548 212331 58256 32767 2 0x4081010 syz-executor0 58256 197899 43891 32767 2 0x490 syz-executor0 43891 134682 80469 0 3 0x82 wait syz-executor0 38596 185415 30519 32767 3 0x90 nanosleep syz-executor1 30519 446059 80469 0 3 0x82 wait syz-executor1 80469 238129 20699 0 3 0x82 thrsleep syz-fuzzer 80469 242306 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 428443 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 72045 20699 0 2 0x4000002 syz-fuzzer 80469 262831 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 388332 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 276510 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 113333 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 501063 20699 0 3 0x4000082 thrsleep syz-fuzzer 80469 83037 20699 0 2 0x4000482 syz-fuzzer 20699 101837 13297 0 3 0x10008a pause ksh 13297 431449 57349 0 3 0x92 select sshd 71137 388477 1 0 3 0x100083 ttyin getty 57349 449274 1 0 3 0x80 select sshd 62748 367616 41290 73 2 0x100090 syslogd 41290 294107 1 0 3 0x100082 netio syslogd 38037 144984 1 77 3 0x100090 poll dhclient 8090 417047 1 0 3 0x80 poll dhclient 40804 453189 0 0 3 0x14200 pgzero zerothread 50258 451717 0 0 3 0x14200 aiodoned aiodoned 36790 451820 0 0 3 0x14200 syncer update 37047 190254 0 0 3 0x14200 cleaner cleaner 50051 492241 0 0 2 0x14200 reaper 16399 226846 0 0 3 0x14200 pgdaemon pagedaemon 11492 167608 0 0 3 0x14200 bored crynlk 68394 340699 0 0 3 0x14200 bored crypto 1074 79590 0 0 3 0x40014200 acpi0 acpi0 79979 25017 0 0 3 0x40014200 idle1 57082 99762 0 0 3 0x14200 bored softnet 6703 485615 0 0 3 0x14200 bored systqmp 94513 355872 0 0 3 0x14200 bored systq 75839 60450 0 0 3 0x40014200 bored softclock 28975 323894 0 0 7 0x40014200 idle0 1 354870 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper