On Fri, Jun 28, 2019 at 10:14:42AM +0530, Anshuman Khandual wrote: > Generic vmemmap_populate_basepages() is used across platforms for vmemmap > as standard or as fallback when huge pages mapping fails. On arm64 it is > used for configs with ARM64_SWAPPER_USES_SECTION_MAPS applicable both for > ARM64_16K_PAGES and ARM64_64K_PAGES which cannot use huge pages because of > alignment requirements. > > This prevents those configs from allocating from device memory for vmemap > mapping as vmemmap_populate_basepages() does not support vmem_altmap. This > enables that required support. Each architecture should evaluate and decide > on enabling device based base page allocation when appropriate. Hence this > keeps it disabled for all architectures to preserve the existing semantics. This commit message doesn't really make sense to me. There's a huge amount of arm64-specific detail, followed by vague references to "this" and "those" and "that" and I lost track of what you're trying to solve. However, I puzzled through the code and I think it does make sense, so: Acked-by: Will Deacon <will@xxxxxxxxxx> assuming you rewrite the commit message. However, this has a dependency on your hot remove series which has open comments from Mark Rutland afaict. Will
