From: Mike Rapoport <rppt@xxxxxxxxxxxxx> Hi, These patches aim to remove CONFIG_HOLES_IN_ZONE and essentially hardwire pfn_valid_within() to 1. The idea is to mark NOMAP pages as reserved in the memory map and restore the intended semantics of pfn_valid() to designate availability of struct page for a pfn. With this the core mm will be able to cope with the fact that it cannot use NOMAP pages and the holes created by NOMAP ranges within MAX_ORDER blocks will be treated correctly even without the need for pfn_valid_within. The patches are boot tested on qemu-system-aarch64. I beleive it would be best to route these via mmotm tree. v4: * rebase on v5.13-rc1 v3: Link: https://lore.kernel.org/lkml/20210422061902.21614-1-rppt@xxxxxxxxxx * Fix minor issues found by Anshuman * Freshen up the declaration of pfn_valid() to make it consistent with pfn_is_map_memory() * Add more Acked-by and Reviewed-by tags, thanks Anshuman and David v2: Link: https://lore.kernel.org/lkml/20210421065108.1987-1-rppt@xxxxxxxxxx * Add check for PFN overflow in pfn_is_map_memory() * Add Acked-by and Reviewed-by tags, thanks David. v1: Link: https://lore.kernel.org/lkml/20210420090925.7457-1-rppt@xxxxxxxxxx * Add comment about the semantics of pfn_valid() as Anshuman suggested * Extend comments about MEMBLOCK_NOMAP, per Anshuman * Use pfn_is_map_memory() name for the exported wrapper for memblock_is_map_memory(). It is still local to arch/arm64 in the end because of header dependency issues. rfc: Link: https://lore.kernel.org/lkml/20210407172607.8812-1-rppt@xxxxxxxxxx Mike Rapoport (4): include/linux/mmzone.h: add documentation for pfn_valid() memblock: update initialization of reserved pages arm64: decouple check whether pfn is in linear map from pfn_valid() arm64: drop pfn_valid_within() and simplify pfn_valid() arch/arm64/Kconfig | 3 --- arch/arm64/include/asm/memory.h | 2 +- arch/arm64/include/asm/page.h | 3 ++- arch/arm64/kvm/mmu.c | 2 +- arch/arm64/mm/init.c | 14 +++++++++++++- arch/arm64/mm/ioremap.c | 4 ++-- arch/arm64/mm/mmu.c | 2 +- include/linux/memblock.h | 4 +++- include/linux/mmzone.h | 11 +++++++++++ mm/memblock.c | 28 ++++++++++++++++++++++++++-- 10 files changed, 60 insertions(+), 13 deletions(-) base-commit: 6efb943b8616ec53a5e444193dccf1af9ad627b5 -- 2.28.0