Re: [PATCH v12 01/14] ARM: mm: add missing pud_page define to 2-level page tables

[Ding Tianhong]

On 2021/2/2 19:13, Russell King - ARM Linux admin wrote:
> On Tue, Feb 02, 2021 at 09:05:02PM +1000, Nicholas Piggin wrote:
>> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
>> index c02f24400369..d63a5bb6bd0c 100644
>> --- a/arch/arm/include/asm/pgtable.h
>> +++ b/arch/arm/include/asm/pgtable.h
>> @@ -166,6 +166,9 @@ extern struct page *empty_zero_page;
>>  
>>  extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>>  
>> +#define pud_page(pud)		pmd_page(__pmd(pud_val(pud)))
>> +#define pud_write(pud)		pmd_write(__pmd(pud_val(pud)))
> 
> As there is no PUD, does it really make sense to return a valid
> struct page (which will be the PTE page) for pud_page(), which is
> several tables above?
> 
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h

+static inline int pud_none(pud_t pud)
+{
+          return 0;
+}

I think it could be fix like this.

Ding