[seL4] vspace_reserve_range_at

Hello, I am trying to create a 1:1 physical to virtual mapping in my root thread. My first step in attempting this is to reserve the virtual address I need using the vspace_reserve_range_at() function, but I get the following error: ERROR:sel4utils_reserve_range_at_no_alloc:585: Range not available at 0xf8f00000, size 0x64000 Is there something I need to do in the kernel or in the root thread to actually allow this memory to be reserved? BTW, I am still using seL4 1.0. Thanks, Robbie VanVossen DornerWorks