[Linux][Memory Mapping]Linear mapping equation among Kernel base , page offset, physical start and memory start

For the linear mapping the following equation should be true: KERNELBASE – PAGE_OFFSET = PHYSICAL_START – MEMORY_START Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START where KERNELBASE ->the virtual address of the start of the kernel PAGE_OFFSET->the virtual address of the start of lowmem PHYSICAL_START-> the physical address of the start of the kernel MEMORY_START