Re: [PATCH v10 04/10] arm64/hugetlb: drop the init_mm special case in clear_flush()

[Uladzislau Rezki <urezki@gmail.com>]

On Fri, Oct 02, 2026 at 05:09:41PM +0800, Wen Jiang wrote:
> clear_flush() calls flush_tlb_kernel_range() when mm is &init_mm. This
> was added by commit 06fc959fcff7 ("arm64/mm: Support huge pte-mapped
> pages in vmap") because vmap called set_huge_pte_at(&init_mm, ...).
> 
> Now that vmap uses pte_set_huge()/pte_clear_huge(), mm/vmalloc.c is no
> longer a caller of set_huge_pte_at() on arm64. The only remaining
> callers passing &init_mm are in arch/powerpc, which uses its own
> implementation. Remove the dead branch.
> 
> No functional change.
> 
> Signed-off-by: Wen Jiang <jiangwen6@xiaomi.com>
> Reviewed-by: Barry Song <baohua@kernel.org>
> ---
>  arch/arm64/mm/hugetlbpage.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
> index 8e799c1fe0aa6..ce247b06fe03d 100644
> --- a/arch/arm64/mm/hugetlbpage.c
> +++ b/arch/arm64/mm/hugetlbpage.c
> @@ -206,10 +206,7 @@ static void clear_flush(struct mm_struct *mm,
>  	for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
>  		__ptep_get_and_clear_anysz(mm, addr, ptep, pgsize);
>  
> -	if (mm == &init_mm)
> -		flush_tlb_kernel_range(saddr, addr);
> -	else
> -		__flush_hugetlb_tlb_range(&vma, saddr, addr, pgsize, TLBF_NOWALKCACHE);
> +	__flush_hugetlb_tlb_range(&vma, saddr, addr, pgsize, TLBF_NOWALKCACHE);
>  }
>  
>  void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
> -- 
> 2.34.1
> 
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>

--
Uladzislau Rezki