[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20100524123200.23e23fd2.akpm@linux-foundation.org>
Date: Mon, 24 May 2010 12:32:00 -0700
From: Andrew Morton <akpm@...ux-foundation.org>
To: Peter Zijlstra <peterz@...radead.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
Nick Piggin <npiggin@...e.de>,
Andrea Arcangeli <aarcange@...hat.com>,
Avi Kivity <avi@...hat.com>,
Thomas Gleixner <tglx@...utronix.de>,
Rik van Riel <riel@...hat.com>, Ingo Molnar <mingo@...e.hu>,
Linus Torvalds <torvalds@...ux-foundation.org>,
linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
David Miller <davem@...emloft.net>,
Hugh Dickins <hugh.dickins@...cali.co.uk>,
Mel Gorman <mel@....ul.ie>
Subject: Re: [PATCH 02/13] mm: Revalidate anon_vma in page_lock_anon_vma()
On Fri, 09 Apr 2010 10:44:53 +0200
Peter Zijlstra <peterz@...radead.org> wrote:
> On Fri, 2010-04-09 at 16:29 +0900, KOSAKI Motohiro wrote:
> >
> >
> > diff --git a/mm/rmap.c b/mm/rmap.c
> > index 8b088f0..b4a0b5b 100644
> > --- a/mm/rmap.c
> > +++ b/mm/rmap.c
> > @@ -295,7 +295,7 @@ struct anon_vma *page_lock_anon_vma(struct page
> > *page)
> > unsigned long anon_mapping;
> >
> > rcu_read_lock();
> > - anon_mapping = (unsigned long) ACCESS_ONCE(page->mapping);
> > + anon_mapping = (unsigned long) rcu_dereference(page->mapping);
> > if ((anon_mapping & PAGE_MAPPING_FLAGS) != PAGE_MAPPING_ANON)
> > goto out;
> > if (!page_mapped(page))
>
> Yes, I think this is indeed required.
>
> I'll do a new version of the patch that includes the comment updates
> requested by Andrew.
Either this didn't happen or I lost the patch.
I parked mm-revalidate-anon_vma-in-page_lock_anon_vma.patch for now.
Hopefully everything still works without it..
--
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/
Powered by blists - more mailing lists