linux-kernel - Re: [PATCH] mm/page_table_check: Drop all redundant EXPORT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CA+CK2bARgsgBAgawfAD8-xzDN6+_sg4zrPQnoTFy4b=ZMx_u1g@mail.gmail.com>
Date:   Wed, 20 Apr 2022 12:54:08 -0400
From:   Pasha Tatashin <pasha.tatashin@...een.com>
To:     Anshuman Khandual <anshuman.khandual@....com>
Cc:     linux-mm <linux-mm@...ck.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] mm/page_table_check: Drop all redundant EXPORT_SYMBOL()

On Wed, Apr 20, 2022 at 2:01 AM Anshuman Khandual
<anshuman.khandual@....com> wrote:
>
> Function definitions need not be exported via EXPORT_SYMBOL() mechanism. In
> this case these functions just get called only inside their wrappers. Even
> __page_table_check_zero() gets called without such an export. Just drop all
> these redundant EXPORT_SYMBOL().
>
> Cc: Pasha Tatashin <pasha.tatashin@...een.com>
> Cc: Andrew Morton <akpm@...ux-foundation.org>
> Cc: linux-mm@...ck.org
> Cc: linux-kernel@...r.kernel.org
> Signed-off-by: Anshuman Khandual <anshuman.khandual@....com>
> ---
> This applies on v5.18-rc3
>
>  mm/page_table_check.c | 6 ------
>  1 file changed, 6 deletions(-)
>
> diff --git a/mm/page_table_check.c b/mm/page_table_check.c
> index 2458281bff89..5c2a96159832 100644
> --- a/mm/page_table_check.c
> +++ b/mm/page_table_check.c
> @@ -167,7 +167,6 @@ void __page_table_check_pte_clear(struct mm_struct *mm, unsigned long addr,
>                                        PAGE_SIZE >> PAGE_SHIFT);
>         }
>  }
> -EXPORT_SYMBOL(__page_table_check_pte_clear);
>
>  void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
>                                   pmd_t pmd)
> @@ -180,7 +179,6 @@ void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
>                                        PMD_PAGE_SIZE >> PAGE_SHIFT);
>         }
>  }
> -EXPORT_SYMBOL(__page_table_check_pmd_clear);
>
>  void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
>                                   pud_t pud)
> @@ -193,7 +191,6 @@ void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
>                                        PUD_PAGE_SIZE >> PAGE_SHIFT);
>         }
>  }
> -EXPORT_SYMBOL(__page_table_check_pud_clear);
>
>  void __page_table_check_pte_set(struct mm_struct *mm, unsigned long addr,
>                                 pte_t *ptep, pte_t pte)
> @@ -208,7 +205,6 @@ void __page_table_check_pte_set(struct mm_struct *mm, unsigned long addr,
>                                      pte_write(pte));
>         }
>  }
> -EXPORT_SYMBOL(__page_table_check_pte_set);

Hi Anshuman,

See this:
https://lore.kernel.org/all/20211124234754.l5co34dUK%25akpm@linux-foundation.org/

The rest of EXPORTs were added to be symmetric, and allow other
drivers to use set_*p**()/clear_p** calls.

Pasha