Re: [PATCH v4 02/12] mm: enable MMU_GATHER_RCU_TABLE_FREE for most 2-level architectures

[Lance Yang <lance.yang@linux.dev>]

On Tue, Sep 22, 2026 at 04:35:33PM +0100, Lorenzo Stoakes (ARM) wrote:
>Commit e3ecf7c7d082 ("mm: pgtable: convert some architectures to use
>tlb_remove_ptdesc()") updated a number of architectures from using
>pagetable_dtor() + tlb_remove_page_ptdesc() to using tlb_remove_ptdesc() in
>__pte_free_tlb().
>
>This is meaningful as tlb_remove_ptdesc() allows for RCU page table
>freeing if CONFIG_MMU_GATHER_RCU_TABLE_FREE is specified.
>
>The csky, hexagon, nios2, openrisc, sh (except X2) and m68k-sun3
>architectures all have 2 levels of page tables, so the only page tables
>ever freed by mmu_gather are PTEs, so this update suffices to ensure that
>every page table freed by the mmu_gather mechanism is freed under RCU.
>
>Therefore, update all of these architectures to select
>CONFIG_MMU_GATHER_RCU_TABLE_FREE.
>
>This forms part of an overall effort to switch every architecture to this
>mode.
>
>Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
>Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
>---

Nothing jumped out at me,

Reviewed-by: Lance Yang <lance.yang@linux.dev>