Re: [PATCH v2 2/5] arm64/mm: drop vmemmap_pmd helpers and use generic code

[Muchun Song <muchun.song@linux.dev>]

> On May 18, 2026, at 20:33, Will Deacon <will@kernel.org> wrote:
> 
> On Sat, Apr 04, 2026 at 08:20:55PM +0800, Muchun Song wrote:
>> The generic implementations now suffice; remove the arm64 copies.
>> 
>> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
>> ---
>> arch/arm64/mm/mmu.c | 14 --------------
>> 1 file changed, 14 deletions(-)
>> 
>> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
>> index ec1c6971a561..b87053452641 100644
>> --- a/arch/arm64/mm/mmu.c
>> +++ b/arch/arm64/mm/mmu.c
>> @@ -1745,20 +1745,6 @@ static void free_empty_tables(unsigned long addr, unsigned long end,
>> }
>> #endif
>> 
>> -void __meminit vmemmap_set_pmd(pmd_t *pmdp, void *p, int node,
>> -       unsigned long addr, unsigned long next)
>> -{
>> - 	pmd_set_huge(pmdp, __pa(p), __pgprot(PROT_SECT_NORMAL));
>> -}
>> -
>> -int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node,
>> - unsigned long addr, unsigned long next)
>> -{
>> - 	vmemmap_verify((pte_t *)pmdp, node, addr, next);
>> -
>> - 	return pmd_sect(READ_ONCE(*pmdp));
>> -}
> 
> I think this is fine:
> 
> Acked-by: Will Deacon <will@kernel.org>

Thanks.

> 
> but note that, since c25c4aa3f79a ("arm64: mm: Add PTE_DIRTY back to
> PAGE_KERNEL* to fix kexec/hibernation"), I think that using PAGE_KERNEL
> (like the generic code does in the first patch of this series) means
> that this change isn't a no-op -- it means that the huge entries will
> now be marked as dirty. That's possibly a bug fix (?)

I think you are right. We should mark kernel mapping as dirty.

Thanks,
Muchun

> 
> Will