uvm_fault(0xffffffff839367d8, 0xffff800027562000, 0, 2) -> d kernel: page fault trap, code=2 Stopped at memset+0x52: repe stosq %es:(%rdi) TID PID UID PRFLAGS PFLAGS CPU COMMAND * 94743 25286 0 0x1000 0x4080000 0K syz-executor memset() at memset+0x52 VOP_WRITE(fffffd805de38b40,ffff80003c5424d8,7,fffffd807f7d2750) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 vn_write(fffffd805e97f8f8,ffff80003c5424d8,0) at vn_write+0x1d4 sys/kern/vfs_vnops.c:408 dofilewritev(ffff8000ffffc2a0,3,ffff80003c5424d8,0,ffff80003c542590) at dofilewritev+0x23c sys/kern/sys_generic.c:380 sys_write(ffff8000ffffc2a0,ffff80003c542640,ffff80003c542590) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff80003c542640) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c542640) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x95b5fcb760, count: 8 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.