Date: Sun, 21 Jun 2015 23:19:51 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>, Benjamin LaHaise <bcrl@kvack.org>,
        Hugh Dickins <hughd@google.com>, Jeff Moyer <jmoyer@redhat.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Andy Lutomirski <luto@kernel.org>
Subject: Re: [PATCH 0/3] special_mapping_fault() is broken
Message-ID: <20150621211951.GA18593@redhat.com>
References: <20150621210725.GA18220@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20150621210725.GA18220@redhat.com>
User-Agent: Mutt/1.5.18 (2008-05-17)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1313
Lines: 37

Forgot to add Andy...

And forgot to mention. As for vdso in particular, I'd actually prefer
to make it have ->vm_file != NULL so that uprobe-in-vdso could work.
But this is not that simple, and I think these fixes (if correct) make
sense in any case, whatever we do with vdso.

On 06/21, Oleg Nesterov wrote:
>
> On 06/20, Oleg Nesterov wrote:
> >
> > Let me first send the changes which look "obviously correct" to me.
> > Perhaps I'll send more patches on top of this later.
>
> But lets also fix another unmap/remap bug before the cleanups...
> This series doesn't depend on the previous mremap fixes.
>
> special_mapping_fault() is absolutely broken. It seems it was always
> wrong, but this didn't matter until vdso/vvar started to use more than
> one page.
>
> I am not sure about 1/3. As the changelog says the name is not very
> accurate, and I do not really like the vma->fault != NULL check. But
> I hope this can work, and we can change this helper later if needed.
>
> Please review.
>
> Oleg.
>
>  include/linux/mm.h |    5 +++++
>  mm/memory.c        |   13 ++++++-------
>  mm/mmap.c          |   14 +++-----------
>  3 files changed, 14 insertions(+), 18 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at  http://www.tux.org/lkml/