linux-kernel - Re: [PATCH 2/5] mm: gup: add __get_user_pages_unlocked to customize gup

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]

Date:	Thu, 30 Oct 2014 14:17:37 +0200
From:	"Kirill A. Shutemov" <kirill@...temov.name>
To:	Andrea Arcangeli <aarcange@...hat.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	Michel Lespinasse <walken@...gle.com>,
	Andrew Jones <drjones@...hat.com>,
	Hugh Dickins <hughd@...gle.com>, Mel Gorman <mgorman@...e.de>,
	Andres Lagar-Cavilla <andreslc@...gle.com>,
	Minchan Kim <minchan@...nel.org>,
	KOSAKI Motohiro <kosaki.motohiro@...il.com>,
	"\\\"Dr. David Alan Gilbert\\\"" <dgilbert@...hat.com>,
	Peter Feiner <pfeiner@...gle.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	James Bottomley <James.Bottomley@...senPartnership.com>,
	David Miller <davem@...emloft.net>,
	Steve Capper <steve.capper@...aro.org>,
	Johannes Weiner <jweiner@...hat.com>
Subject: Re: [PATCH 2/5] mm: gup: add __get_user_pages_unlocked to customize
 gup_flags

On Wed, Oct 29, 2014 at 05:35:17PM +0100, Andrea Arcangeli wrote:
> Some caller (like KVM) may want to set the gup_flags like
> FOLL_HWPOSION to get a proper -EHWPOSION retval instead of -EFAULT to
> take a more appropriate action if get_user_pages runs into a memory
> failure.
> 
> Signed-off-by: Andrea Arcangeli <aarcange@...hat.com>
> ---
>  include/linux/mm.h |  4 ++++
>  mm/gup.c           | 44 ++++++++++++++++++++++++++++++++------------
>  mm/nommu.c         | 16 +++++++++++++---
>  3 files changed, 49 insertions(+), 15 deletions(-)
> 
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 99831d9..9a5ada3 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1222,6 +1222,10 @@ long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm,
>  		    unsigned long start, unsigned long nr_pages,
>  		    int write, int force, struct page **pages,
>  		    int *locked);
> +long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
> +			       unsigned long start, unsigned long nr_pages,
> +			       int write, int force, struct page **pages,
> +			       unsigned int gup_flags);
>  long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
>  		    unsigned long start, unsigned long nr_pages,
>  		    int write, int force, struct page **pages);
> diff --git a/mm/gup.c b/mm/gup.c
> index a8521f1..01534ff 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -591,9 +591,9 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
>  						int write, int force,
>  						struct page **pages,
>  						struct vm_area_struct **vmas,
> -						int *locked, bool notify_drop)
> +						int *locked, bool notify_drop,
> +						unsigned int flags)

Argument list getting too long. Should we consider packing them into a
struct?

-- 
 Kirill A. Shutemov
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/