Re: [PATCH v2 -next] riscv: mm: fix build errors caused by mk_pmd()

[Palmer Dabbelt]

On Thu, 17 Jun 2021 02:58:31 PDT (-0700), sunnanyong@xxxxxxxxxx wrote:
> With "riscv: mm: add THP support on 64-bit", mk_pmd() function
> introduce build errors,
> 1.build with CONFIG_ARCH_RV32I=y:
> arch/riscv/include/asm/pgtable.h: In function 'mk_pmd':
> arch/riscv/include/asm/pgtable.h:513:9: error: implicit declaration of function 'pfn_pmd';
>  did you mean 'pfn_pgd'? [-Werror=implicit-function-declaration]
>
> 2.build with CONFIG_SPARSEMEM=y && CONFIG_SPARSEMEM_VMEMMAP=n
> arch/riscv/include/asm/pgtable.h: In function 'mk_pmd':
> include/asm-generic/memory_model.h:64:14: error: implicit declaration of function 'page_to_section';
>  did you mean 'present_section'? [-Werror=implicit-function-declaration]
>
> Move the definition of mk_pmd to pgtable-64.h to fix the first error.
> Use macro definition instead of inline function for mk_pmd
> to fix the second problem. It is similar to the mk_pte macro.
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Signed-off-by: Nanyong Sun <sunnanyong@xxxxxxxxxx>
> ---
> Changes in v2:
> - Move mk_pmd to pgtable-64.h
> ---
>  arch/riscv/include/asm/pgtable-64.h | 2 ++
>  arch/riscv/include/asm/pgtable.h    | 5 -----
>  2 files changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
> index 1439017b16f8..228261aa9628 100644
> --- a/arch/riscv/include/asm/pgtable-64.h
> +++ b/arch/riscv/include/asm/pgtable-64.h
> @@ -79,6 +79,8 @@ static inline unsigned long _pmd_pfn(pmd_t pmd)
>  	return pmd_val(pmd) >> _PAGE_PFN_SHIFT;
>  }
>
> +#define mk_pmd(page, prot)    pfn_pmd(page_to_pfn(page), prot)
> +
>  #define pmd_ERROR(e) \
>  	pr_err("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
>
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index 5ae51e6bd5ab..6bc2582f82e9 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -516,11 +516,6 @@ static inline unsigned long pmd_pfn(pmd_t pmd)
>  	return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT);
>  }
>
> -static inline pmd_t mk_pmd(struct page *page, pgprot_t prot)
> -{
> -	return pfn_pmd(page_to_pfn(page), prot);
> -}
> -
>  static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
>  {
>  	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));

Thanks, this is on for-next.