Re: [PATCH 3/4] riscv/mm: fix missing destructor for hotplug PUD tables

[David Hildenbrand (Arm)]

On 10/8/26 09:30, Muchun Song wrote:
> Commit 8472cc4503eb ("riscv: mm: call PUD/P4D ctor in special kernel
> pgtable alloc") made alloc_pud_late() run the PUD page-table constructor.
> However, free_pud_table() still frees non-reserved PUD tables directly
> without decrementing NR_PAGETABLE.
> 
> Free PUD tables through the common free_pagetable() helper so that
> constructor-backed tables run the matching destructor before being
> freed.
> 
> Fixes: 8472cc4503eb ("riscv: mm: call PUD/P4D ctor in special kernel pgtable alloc")
> Cc: stable@xxxxxxxxxxxxxxx
> Assisted-by: LLM
> Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
> ---
>  arch/riscv/mm/init.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 429a0b015ec1..62077539ee78 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -1540,10 +1540,7 @@ static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
>  			return;
>  	}
>  
> -	if (PageReserved(page))
> -		free_reserved_page(page);
> -	else
> -		__free_pages(page, 0);
> +	free_pagetable(page);
>  	p4d_clear(p4d);
>  }
>  

Routing this through a single helper looks correct.

Acked-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>

-- 
Cheers,

David