uvm_fault(0xffffffff839d13e0, 0xffff8000264b2000, 0, 2) -> d kernel: page fault trap, code=2 Stopped at memset+0x52: repe stosq %es:(%rdi) TID PID UID PRFLAGS PFLAGS CPU COMMAND 348944 67645 0 0 0 0 syz-executor memset() at memset+0x52 ffs_write(ffff80002a26e040) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345 VOP_WRITE(fffffd806d9846f8,ffff80002a26e0d0,0,fffffd80097fd270) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 uvn_io(fffffd806ede4558,ffff80002a26e250,10,39,1) at uvn_io+0x498 sys/uvm/uvm_vnode.c:1232 uvm_pager_put(fffffd806ede4558,fffffd80087c6c10,ffff80002a26e2f0,ffff80002a26e314,39,0,b9f60f3633dafc15) at uvm_pager_put+0x10a sys/uvm/uvm_pager.c:505 uvn_flush(fffffd806ede4558,0,0,19) at uvn_flush+0x690 sys/uvm/uvm_vnode.c:705 uvn_detach(fffffd806ede4558) at uvn_detach+0xcf sys/uvm/uvm_vnode.c:344 uvm_unmap_detach(ffff80002a26e420,0) at uvm_unmap_detach+0x15e sys/uvm/uvm_map.c:1370 uvm_map_teardown(fffffd806e8b4b80) at uvm_map_teardown+0x360 sys/uvm/uvm_map.c:2536 exit1(ffff80002a242a70,43,0,1) at exit1+0x6fc sys/kern/kern_exit.c:260 sys_exit(ffff80002a242a70,ffff80002a26e5f0,ffff80002a26e540) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002a26e5f0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a26e5f0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7efd72fbcb50, count: 2 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}> set $maxwidth = 0 ddb{1}>