Re: [PATCH v2 4/5] mm,memory_hotplug: allocate memmap from the added memory range for sparse-vmemmap

From: Anshuman Khandual
Date: Wed Jun 26 2019 - 04:17:15 EST


Hello Oscar,

On 06/25/2019 01:22 PM, Oscar Salvador wrote:
> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index 93ed0df4df79..d4b5661fa6b6 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -765,7 +765,10 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
> if (pmd_none(READ_ONCE(*pmdp))) {
> void *p = NULL;
>
> - p = vmemmap_alloc_block_buf(PMD_SIZE, node);
> + if (altmap)
> + p = altmap_alloc_block_buf(PMD_SIZE, altmap);
> + else
> + p = vmemmap_alloc_block_buf(PMD_SIZE, node);
> if (!p)
> return -ENOMEM;

Is this really required to be part of this series ? I have an ongoing work
(reworked https://patchwork.kernel.org/patch/10882781/) enabling altmap
support on arm64 during memory hot add and remove path which is waiting on
arm64 memory-hot remove to be merged first.

- Anshuman