On Sun, Nov 01, 2020 at 07:04:50PM +0200, Mike Rapoport wrote: > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > ARM and ARM64 free unused parts of the memory map just before the > initialization of the page allocator. To allow holes in the memory map both > architectures overload pfn_valid() and define HAVE_ARCH_PFN_VALID. > > Allowing holes in the memory map for FLATMEM may be useful for small > machines, such as ARC and m68k and will enable those architectures to cease > using DISCONTIGMEM and still support more than one memory bank. > > Move the functions that free unused memory map to generic mm and enable > them in case HAVE_ARCH_PFN_VALID=y. > > Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> For arm64: Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>