linux-kernel - Re: [PATCH v2 3/4] mm/gup: remove unused pin_user_pages

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: <20220201121034.4jyyymqlvfx2grfy@quack3.lan>
Date:   Tue, 1 Feb 2022 13:10:34 +0100
From:   Jan Kara <jack@...e.cz>
To:     John Hubbard <jhubbard@...dia.com>
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        Peter Xu <peterx@...hat.com>, Jason Gunthorpe <jgg@...pe.ca>,
        David Hildenbrand <david@...hat.com>, Jan Kara <jack@...e.cz>,
        Claudio Imbrenda <imbrenda@...ux.ibm.com>,
        "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>,
        Alex Williamson <alex.williamson@...hat.com>,
        Andrea Arcangeli <aarcange@...hat.com>,
        LKML <linux-kernel@...r.kernel.org>, linux-mm@...ck.org,
        Jason Gunthorpe <jgg@...dia.com>
Subject: Re: [PATCH v2 3/4] mm/gup: remove unused pin_user_pages_locked()

On Tue 01-02-22 02:11:07, John Hubbard wrote:
> This routine was used for a short while, but then the calling code was
> refactored and the only caller was removed.
> 
> Reviewed-by: David Hildenbrand <david@...hat.com>
> Reviewed-by: Jason Gunthorpe <jgg@...dia.com>
> Signed-off-by: John Hubbard <jhubbard@...dia.com>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@...e.cz>

								Honza

> ---
>  include/linux/mm.h |  2 --
>  mm/gup.c           | 29 -----------------------------
>  2 files changed, 31 deletions(-)
> 
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 213cc569b192..80c540c17d83 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1918,8 +1918,6 @@ long pin_user_pages(unsigned long start, unsigned long nr_pages,
>  		    struct vm_area_struct **vmas);
>  long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
>  		    unsigned int gup_flags, struct page **pages, int *locked);
> -long pin_user_pages_locked(unsigned long start, unsigned long nr_pages,
> -		    unsigned int gup_flags, struct page **pages, int *locked);
>  long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
>  		    struct page **pages, unsigned int gup_flags);
>  long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
> diff --git a/mm/gup.c b/mm/gup.c
> index 8633bca12eab..58d01a96ab30 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -3120,32 +3120,3 @@ long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
>  	return get_user_pages_unlocked(start, nr_pages, pages, gup_flags);
>  }
>  EXPORT_SYMBOL(pin_user_pages_unlocked);
> -
> -/*
> - * pin_user_pages_locked() is the FOLL_PIN variant of get_user_pages_locked().
> - * Behavior is the same, except that this one sets FOLL_PIN and rejects
> - * FOLL_GET.
> - */
> -long pin_user_pages_locked(unsigned long start, unsigned long nr_pages,
> -			   unsigned int gup_flags, struct page **pages,
> -			   int *locked)
> -{
> -	/*
> -	 * FIXME: Current FOLL_LONGTERM behavior is incompatible with
> -	 * FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on
> -	 * vmas.  As there are no users of this flag in this call we simply
> -	 * disallow this option for now.
> -	 */
> -	if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM))
> -		return -EINVAL;
> -
> -	/* FOLL_GET and FOLL_PIN are mutually exclusive. */
> -	if (WARN_ON_ONCE(gup_flags & FOLL_GET))
> -		return -EINVAL;
> -
> -	gup_flags |= FOLL_PIN;
> -	return __get_user_pages_locked(current->mm, start, nr_pages,
> -				       pages, NULL, locked,
> -				       gup_flags | FOLL_TOUCH);
> -}
> -EXPORT_SYMBOL(pin_user_pages_locked);
> -- 
> 2.35.1
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR