uvm_fault(0xffffffff838b92d0, 0xffff800028815040, 0, 2) -> d kernel: page fault trap, code=2 Stopped at memset+0x52: repe stosq %es:(%rdi) TID PID UID PRFLAGS PFLAGS CPU COMMAND memset() at memset+0x52 ffs_write(ffff80002f0f1130) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401 VOP_WRITE(fffffd806aec57b0,ffff80002f0f11c8,23,fffffd8007bfd2d8) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_rdwr(1,fffffd806aec57b0,ffff80002f0f1300,40,0,1,add47543b544c4c6,0,1008,0) at vn_rdwr+0x12d sys/kern/vfs_vnops.c:324 acct_process(ffff800034104fb0) at acct_process+0x7a2 sys/kern/kern_acct.c:245 exit1(ffff800034104fb0,0,0,1) at exit1+0x5c4 sys/kern/kern_exit.c:228 sys_exit(ffff800034104fb0,ffff80002f0f1530,ffff80002f0f1480) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002f0f1530) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002f0f1530) at syscall+0x962 sys/arch/amd64/amd64/trap.c:775 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f517c6e1ef0, 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.