Re: [PATCH 0/3] mm: Generalize page table allocation helpers

[Mike Rapoport <rppt@kernel.org>]

On Wed, Oct 14, 2026 at 11:59:07AM +0800, Muchun Song wrote:
> A subsequent series will switch runtime vmemmap population to the
> generic page-table allocators. Since vmemmap tables belong to init_mm,
> the allocators must select GFP_PGTABLE_KERNEL and mark the ptdesc as a
> kernel page table.
> 
> Some architecture-specific allocators do not preserve both semantics.
> LoongArch and MIPS choose PMD/PUD GFP flags without checking the mm,
> which can charge kernel PMD tables to a memcg and leave user PUD tables
> unaccounted. The private PMD/PUD allocators also omit kernel ptdesc
> marking.
> 
> Rather than duplicate this handling in each architecture, extend the
> generic PTE, PMD and PUD allocators to support architecture
> initialization hooks and non-zero table orders. LoongArch, MIPS and
> parisc can then drop their private allocators and inherit the generic
> GFP selection and ptdesc handling.
> 
> This series only prepares the allocation interfaces; the runtime
> vmemmap conversion will be submitted separately.
> 
> Muchun Song (3):
>   mm: generalize kernel PTE table allocation
>   mm: generalize PMD page table allocation
>   mm: generalize PUD page table allocation

Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

>  arch/loongarch/include/asm/pgalloc.h | 48 ----------------------------
>  arch/mips/include/asm/pgalloc.h      | 40 -----------------------
>  arch/parisc/include/asm/pgalloc.h    | 17 ----------
>  include/asm-generic/pgalloc.h        | 29 ++++++++++++++---
>  4 files changed, 24 insertions(+), 110 deletions(-)
> 
> 
> base-commit: ad9f2d463666c64e94b04be5263c9bf8f9f96fb7
> -- 
> 2.54.0
> 

-- 
Sincerely yours,
Mike.