uvm_fault(0xfffffd8067fb8b98, 0x0, 0, 1) -> e fatal page fault in supervisor mode trap type 6 code 0 rip ffffffff81a6d568 cs 8 rflags 10246 cr2 0 cpl 0 rsp ffff80002a33cf00 gsbase 0xffff8000299edff0 kgsbase 0x0 panic: trap type 6, code=0, pc=ffffffff81a6d568 Starting stack trace... panic(ffffffff833a2066) at panic+0x1d0 sys/kern/subr_prf.c:229 kerntrap(ffff80002a33ce50) at kerntrap+0x30b alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff80000159d000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:586 dtclose(21e5f,81,2000,ffff80002fbfb500) at dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(21e5f,81,2000,ffff80002fbfb500) at dtclose+0x109 sys/dev/dt/dt_dev.c:232 spec_close(ffff80002a33d000) at spec_close+0x466 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805ce56e58,81,fffffd80097fb0d0,ffff80002fbfb500) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd805e54e2b8,ffff80002fbfb500) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd805e54e2b8,ffff80002fbfb500) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd805e54e2b8,ffff80002fbfb500) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd805e54e2b8,ffff80002fbfb500) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80002fbfb500) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80002fbfb500,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002fbfb500,ffff80002a33d370,ffff80002a33d2c0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002a33d370) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a33d370) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x790df36f9d60, count: 242 End of stack trace. WARNING: SPL NOT LOWERED ON SYSCALL 83 -809722736 EXIT 0 4 Stopped at savectx+0xae: movl $0,%gs:0x688 TID PID UID PRFLAGS PFLAGS CPU COMMAND *237864 80835 0 0 0x4000000 1 syz-executor 411414 73674 0 0x14000 0x40000200 0 softclock savectx() at savectx+0xae end of kernel end trace frame: 0xa4ef11ac7a0, count: 14 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.