This patch series update memmap on memory feature to fall back to memmap allocation outside the memory block if the alignment rules are not met. This makes the feature more useful on architectures like ppc64 where alignment rules are different with 64K page size. This patch series is dependent on dax vmemmap optimization series posted here https://lore.kernel.org/linux-mm/20230718022934.90447-1-aneesh.kumar@xxxxxxxxxxxxx/ Changes from v4: * Use altmap.free instead of altmap.reserve * Address review feedback Changes from v3: * Extend the module parameter memmap_on_memory to force allocation even though we can waste hotplug memory. Changes from v2: * Rebase to latest linus tree * Redo the series based on review feedback. Multiple changes to the patchset. Changes from v1: * update the memblock to store vmemmap_altmap details. This is required so that when we remove the memory we can find the altmap details which is needed on some architectures. * rebase to latest linus tree Aneesh Kumar K.V (7): mm/hotplug: Simplify ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE kconfig mm/hotplug: Allow memmap on memory hotplug request to fallback mm/hotplug: Allow architecture to override memmap on memory support check mm/hotplug: Support memmap_on_memory when memmap is not aligned to pageblocks powerpc/book3s64/memhotplug: Enable memmap on memory for radix mm/hotplug: Embed vmem_altmap details in memory block mm/hotplug: Enable runtime update of memmap_on_memory parameter .../admin-guide/mm/memory-hotplug.rst | 12 ++ arch/arm64/Kconfig | 4 +- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/pgtable.h | 24 +++ .../platforms/pseries/hotplug-memory.c | 3 +- arch/x86/Kconfig | 4 +- drivers/acpi/acpi_memhotplug.c | 3 +- drivers/base/memory.c | 32 ++- include/linux/memory.h | 8 +- include/linux/memory_hotplug.h | 3 +- mm/Kconfig | 3 + mm/memory_hotplug.c | 201 ++++++++++++++---- 12 files changed, 229 insertions(+), 69 deletions(-) -- 2.41.0
