Re: [PATCH 1/2] arm64/mm: Export contpte symbols only to GPL users

[John Hubbard <jhubbard@nvidia.com>]

On 2/26/24 04:03, Ryan Roberts wrote:
> The contpte symbols must be exported since some of the public inline
> ptep_* APIs are called from modules and these inlines now call the
> contpte functions. Originally they were exported as EXPORT_SYMBOL() for
> fear of breaking out-of-tree modules. But we subsequently concluded that
> EXPORT_SYMBOL_GPL() should be safe since these functions are deeply core
> mm routines, and any module operating at this level is not going to be
> able to survive on EXPORT_SYMBOL alone.
> 
> Link: https://lore.kernel.org/linux-mm/f9fc2b31-11cb-4969-8961-9c89fea41b74@nvidia.com/
> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
> ---
>   arch/arm64/mm/contpte.c | 22 +++++++++++-----------
>   1 file changed, 11 insertions(+), 11 deletions(-)
> 

Yes, looks good.

Reviewed-by:  John Hubbard <jhubbard@nvidia.com>


thanks,
-- 
John Hubbard
NVIDIA


> diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c
> index 16788f07716d..be0a226c4ff9 100644
> --- a/arch/arm64/mm/contpte.c
> +++ b/arch/arm64/mm/contpte.c
> @@ -135,7 +135,7 @@ void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
>   	pte = pte_mkcont(pte);
>   	contpte_convert(mm, addr, orig_ptep, pte);
>   }
> -EXPORT_SYMBOL(__contpte_try_fold);
> +EXPORT_SYMBOL_GPL(__contpte_try_fold);
>   
>   void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
>   			pte_t *ptep, pte_t pte)
> @@ -150,7 +150,7 @@ void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
>   	pte = pte_mknoncont(pte);
>   	contpte_convert(mm, addr, ptep, pte);
>   }
> -EXPORT_SYMBOL(__contpte_try_unfold);
> +EXPORT_SYMBOL_GPL(__contpte_try_unfold);
>   
>   pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte)
>   {
> @@ -178,7 +178,7 @@ pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte)
>   
>   	return orig_pte;
>   }
> -EXPORT_SYMBOL(contpte_ptep_get);
> +EXPORT_SYMBOL_GPL(contpte_ptep_get);
>   
>   pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
>   {
> @@ -231,7 +231,7 @@ pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
>   
>   	return orig_pte;
>   }
> -EXPORT_SYMBOL(contpte_ptep_get_lockless);
> +EXPORT_SYMBOL_GPL(contpte_ptep_get_lockless);
>   
>   void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
>   					pte_t *ptep, pte_t pte, unsigned int nr)
> @@ -274,7 +274,7 @@ void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
>   
>   	} while (addr != end);
>   }
> -EXPORT_SYMBOL(contpte_set_ptes);
> +EXPORT_SYMBOL_GPL(contpte_set_ptes);
>   
>   void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
>   				pte_t *ptep, unsigned int nr, int full)
> @@ -282,7 +282,7 @@ void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
>   	contpte_try_unfold_partial(mm, addr, ptep, nr);
>   	__clear_full_ptes(mm, addr, ptep, nr, full);
>   }
> -EXPORT_SYMBOL(contpte_clear_full_ptes);
> +EXPORT_SYMBOL_GPL(contpte_clear_full_ptes);
>   
>   pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
>   				unsigned long addr, pte_t *ptep,
> @@ -291,7 +291,7 @@ pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
>   	contpte_try_unfold_partial(mm, addr, ptep, nr);
>   	return __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
>   }
> -EXPORT_SYMBOL(contpte_get_and_clear_full_ptes);
> +EXPORT_SYMBOL_GPL(contpte_get_and_clear_full_ptes);
>   
>   int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
>   					unsigned long addr, pte_t *ptep)
> @@ -316,7 +316,7 @@ int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
>   
>   	return young;
>   }
> -EXPORT_SYMBOL(contpte_ptep_test_and_clear_young);
> +EXPORT_SYMBOL_GPL(contpte_ptep_test_and_clear_young);
>   
>   int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
>   					unsigned long addr, pte_t *ptep)
> @@ -337,7 +337,7 @@ int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
>   
>   	return young;
>   }
> -EXPORT_SYMBOL(contpte_ptep_clear_flush_young);
> +EXPORT_SYMBOL_GPL(contpte_ptep_clear_flush_young);
>   
>   void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
>   					pte_t *ptep, unsigned int nr)
> @@ -355,7 +355,7 @@ void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
>   	contpte_try_unfold_partial(mm, addr, ptep, nr);
>   	__wrprotect_ptes(mm, addr, ptep, nr);
>   }
> -EXPORT_SYMBOL(contpte_wrprotect_ptes);
> +EXPORT_SYMBOL_GPL(contpte_wrprotect_ptes);
>   
>   int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
>   					unsigned long addr, pte_t *ptep,
> @@ -401,4 +401,4 @@ int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
>   
>   	return 1;
>   }
> -EXPORT_SYMBOL(contpte_ptep_set_access_flags);
> +EXPORT_SYMBOL_GPL(contpte_ptep_set_access_flags);