uvm_fault(0xffffffff83a2d578, 0xffff8000281f20a0, 0, 1) -> d kernel: page fault trap, code=0 Stopped at ffs2_balloc+0xa0a: movq 0(%rcx,%rax,8),%r14 TID PID UID PRFLAGS PFLAGS CPU COMMAND *501585 79204 0 0x2 0x1 0 syz-executor ffs2_balloc(fffff5806ee3f400,82c35,50,fffff58007ffd6e8,1,ffff80002a7f1388) at ffs2_balloc+0xa0a sys/ufs/ffs/ffs_balloc.c:614 ffs_write(ffff80002a7f1410) at ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345 VOP_WRITE(fffff5806fa8f568,ffff80002a7f14c0,3,fffff58007ffd6e8) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a779768,fffff5806fa8f568,fffff58007ffd6e8,ffff80002a7f1590,ffff80002a7f1570) at ktrwriteraw+0x19b sys/kern/kern_ktrace.c:692 ktrsysret(ffff80002a779768,5b,0,ffff80002a7f1650) at ktrsysret+0x17f ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrsysret(ffff80002a779768,5b,0,ffff80002a7f1650) at ktrsysret+0x17f sys/kern/kern_ktrace.c:209 syscall(ffff80002a7f1700) at syscall+0xad9 mi_syscall_return sys/sys/syscall_mi.h:204 [inline] syscall(ffff80002a7f1700) at syscall+0xad9 sys/arch/amd64/amd64/trap.c:804 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ea7dfdf6d60, 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. ddb> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: uvm_fault(0xffffffff83a2d578, 0xffff8000281f20a0, 0, 1) -> d ddb>