uvm_fault(0xfffffd806c9dd018, 0x18, 0, 1) -> e kernel: page fault trap, code=0 Stopped at mtx_enter+0x6e: movq 0(%r14),%rax TID PID UID PRFLAGS PFLAGS CPU COMMAND *290642 33101 0 0 0x4000000 0 syz-executor mtx_enter(18) at mtx_enter+0x6e sys/kern/kern_lock.c:335 clockintr_unbind(ffff800001517130,1) at clockintr_unbind+0x56 sys/kern/kern_clockintr.c:375 dt_ioctl_record_stop(ffff8000014f9e00) at dt_ioctl_record_stop+0xbc sys/dev/dt/dt_dev.c:589 dtclose(11e5f,81,2000,ffff80002f8f07e0) at dtclose+0xd9 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(11e5f,81,2000,ffff80002f8f07e0) at dtclose+0xd9 sys/dev/dt/dt_dev.c:239 spec_close(ffff80003c53ed20) at spec_close+0x466 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8076368710,81,fffffd8007bfd958,ffff80002f8f07e0) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156 vn_closefile(fffffd8066bd0cb8,ffff80002f8f07e0) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd8066bd0cb8,ffff80002f8f07e0) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd8066bd0cb8,ffff80002f8f07e0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd8066bd0cb8,ffff80002f8f07e0) at closef+0x190 sys/kern/kern_descrip.c:1264 syscall(ffff80003c53ef70) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80003c53ef70) at syscall+0x962 sys/arch/amd64/amd64/trap.c:775 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xbd0ea3efa00, count: 4 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.