Re: [PATCH] mm/pgtable: convert pgtable_t to ptdesc pointer

[Alex Shi <seakeel@gmail.com>]

On 2026/1/8 10:23, Alex Shi wrote:
> 
> 
> On 2026/1/7 22:48, Matthew Wilcox wrote:
>> On Wed, Jan 07, 2026 at 05:28:36PM +0800, Alex Shi wrote:
>>> Right, I will fix this. and sent the 2nd version.
>> No, the patch is stupid and wrong.  Don't send a v2.  You seem to have a
>> hairtrigger resend, so I'm trying to prevent a v2 being sent instead of
>> sending a patient reply.
> 
> Hi Matthew,
> 
> I hear you—no v2 will be sent.
> but sorry for a bit confusing, what's your expected fix? is the too 
> quick resenting? or the direction to alignment pgtable_t with ptdesc is 
> wrong?

Hi Willy, Do you mind to share the detailed concern for this patch?

Thanks

> 
> If it's the first. the new change for review address Mike's concern.
> diff --git a/arch/arm/include/asm/pgalloc.h b/arch/arm/include/asm/ 
> pgalloc.h
> index a17f01235c29..a204c3ac800a 100644
> --- a/arch/arm/include/asm/pgalloc.h
> +++ b/arch/arm/include/asm/pgalloc.h
> @@ -94,13 +94,13 @@ pte_alloc_one_kernel(struct mm_struct *mm)
>   static inline pgtable_t
>   pte_alloc_one(struct mm_struct *mm)
>   {
> -       struct page *pte;
> +       struct ptdesc *pte;
> 
>          pte = __pte_alloc_one(mm, GFP_PGTABLE_USER | PGTABLE_HIGHMEM);
>          if (!pte)
>                  return NULL;
> -       if (!PageHighMem(pte))
> -               clean_pte_table(page_address(pte));
> +       if (!PageHighMem(ptdesc_page(pte)))
> +               clean_pte_table(ptdesc_address(pte));
>          return pte;
>   }
> 
> @@ -141,7 +141,7 @@ pmd_populate(struct mm_struct *mm, pmd_t *pmdp, 
> pgtable_t ptep)
>          else
>                  prot = _PAGE_USER_TABLE;
> 
> -       __pmd_populate(pmdp, page_to_phys(ptep), prot);
> +       __pmd_populate(pmdp, page_to_phys(ptdesc_page(ptep)), prot);
>   }
> 
>   #endif /* CONFIG_MMU */