uvm_fault(0xffffffff835d1150, 0xffff800019294e06, 0, 2) -> d kernel: page fault trap, code=2 Stopped at memset+0x49: repe stosb %es:(%rdi) TID PID UID PRFLAGS PFLAGS CPU COMMAND * 39721 29736 73 0x1100010 0x1 0 syslogd memset() at memset+0x49 ffs_write(ffff80002a4dcd90) at ffs_write+0xbab sys/ufs/ffs/ffs_vnops.c:401 VOP_WRITE(fffffd8064c0a8b8,ffff80002a4dce40,3,fffffd807f7d74e0) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a4b1960,fffffd8064c0a8b8,fffffd807f7d74e0,ffff80002a4dcf08,ffff80002a4dcee0) at ktrwriteraw+0x191 sys/kern/kern_ktrace.c:682 ktrstruct(ffff80002a4b1960,ffffffff83066c11,ffff80002a4dd040,70) at ktrstruct+0x18b sys/kern/kern_ktrace.c:308 iovec_copyin(7f2867f40900,ffff80002a4dd0f8,ffff80002a4dd040,7,ffff80002a4dd0f0) at iovec_copyin+0x201 sys/kern/sys_generic.c:120 sys_writev(ffff80002a4b1960,ffff80002a4dd230,ffff80002a4dd180) at sys_writev+0x67 sys/kern/sys_generic.c:319 syscall(ffff80002a4dd230) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f2867f3e660, count: 6 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.