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Re: [PATCH] mm: replace vma_lock_anon_vma with anon_vma_lock_read/write

From "Kirill A. Shutemov" <kirill@shutemov.name>
Newsgroups linux.kernel
Subject Re: [PATCH] mm: replace vma_lock_anon_vma with anon_vma_lock_read/write
Date 2016-02-02 10:30 +0100
Message-ID <qXFrz-sR-3@gated-at.bofh.it> (permalink)
References <qXFhU-mN-15@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On Tue, Feb 02, 2016 at 12:10:19PM +0300, Konstantin Khlebnikov wrote:
> Sequence vma_lock_anon_vma() - vma_unlock_anon_vma() isn't safe if
> anon_vma appeared between lock and unlock. We have to check anon_vma
> first or call anon_vma_prepare() to be sure that it's here. There are
> only few users of these legacy helpers. Let's get rid of them.
> 
> This patch fixes anon_vma lock imbalance in validate_mm().
> Write lock isn't required here, read lock is enough.
> 
> And reorders expand_downwards/expand_upwards: security_mmap_addr() and
> wrapping-around check don't have to be under anon vma lock.
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Reported-by: Dmitry Vyukov <dvyukov@google.com>
> Link: https://lkml.kernel.org/r/CACT4Y+Y908EjM2z=706dv4rV6dWtxTLK9nFg9_7DhRMLppBo2g@mail.gmail.com

Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

-- 
 Kirill A. Shutemov

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[PATCH] mm: replace vma_lock_anon_vma with anon_vma_lock_read/write Konstantin Khlebnikov <koct9i@gmail.com> - 2016-02-02 10:20 +0100
  Re: [PATCH] mm: replace vma_lock_anon_vma with  anon_vma_lock_read/write "Kirill A. Shutemov" <kirill@shutemov.name> - 2016-02-02 10:30 +0100

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