From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Erez Zadok" <ezk@cs.sunysb.edu>
Cc: "Hugh Dickins" <hugh@veritas.com>,
"Ryan Finnie" <ryan@finnie.org>,
"Andrew Morton" <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
cjwatson@ubuntu.com, linux-mm@kvack.org
Subject: Re: msync(2) bug(?), returns AOP_WRITEPAGE_ACTIVATE to userland
Date: Mon, 15 Oct 2007 14:47:52 +0300 [thread overview]
Message-ID: <84144f020710150447o94b1babo8b6e6a647828465f@mail.gmail.com> (raw)
In-Reply-To: <200710142232.l9EMW8kK029572@agora.fsl.cs.sunysb.edu>
Hi,
On 10/15/07, Erez Zadok <ezk@cs.sunysb.edu> wrote:
> Pekka, with a small change to your patch (to handle time-based cache
> coherency), your patch worked well and passed all my tests. Thanks.
>
> So now I wonder if we still need the patch to prevent AOP_WRITEPAGE_ACTIVATE
> from being returned to userland. I guess we still need it, b/c even with
> your patch, generic_writepages() can return AOP_WRITEPAGE_ACTIVATE back to
> the VFS and we need to ensure that doesn't "leak" outside the kernel.
I wonder whether _not setting_ BDI_CAP_NO_WRITEBACK implies that
->writepage() will never return AOP_WRITEPAGE_ACTIVATE for
!wbc->for_reclaim case which would explain why we haven't hit this bug
before. Hugh, Andrew?
And btw, I think we need to fix ecryptfs too.
Pekka
next prev parent reply other threads:[~2007-10-15 11:47 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-10-07 19:20 msync(2) bug(?), returns AOP_WRITEPAGE_ACTIVATE to userland Erez Zadok
2007-10-11 21:47 ` Andrew Morton
2007-10-11 22:12 ` Ryan Finnie
2007-10-12 0:38 ` Hugh Dickins
2007-10-12 21:45 ` Pekka Enberg
2007-10-14 8:44 ` Hugh Dickins
2007-10-14 17:09 ` Pekka Enberg
2007-10-14 17:23 ` Erez Zadok
2007-10-14 17:50 ` Pekka J Enberg
2007-10-14 22:32 ` Erez Zadok
2007-10-15 11:47 ` Pekka Enberg [this message]
2007-10-16 18:02 ` Erez Zadok
2007-10-22 20:16 ` Hugh Dickins
2007-10-22 20:48 ` Pekka Enberg
2007-10-25 15:36 ` Hugh Dickins
2007-10-25 16:44 ` Erez Zadok
2007-10-25 18:23 ` Hugh Dickins
2007-10-26 2:00 ` Neil Brown
2007-10-26 8:09 ` Pekka Enberg
2007-10-26 11:26 ` Hugh Dickins
2007-10-26 8:05 ` Pekka Enberg
2007-10-22 21:04 ` Erez Zadok
2007-10-25 16:40 ` Hugh Dickins
2007-10-24 21:02 ` [PATCH] fix tmpfs BUG and AOP_WRITEPAGE_ACTIVATE Hugh Dickins
2007-10-24 21:08 ` Andrew Morton
2007-10-24 21:37 ` [PATCH+comment] " Hugh Dickins
2007-10-25 5:37 ` Pekka Enberg
2007-10-25 6:30 ` Hugh Dickins
2007-10-25 7:24 ` Pekka Enberg
2007-10-25 16:01 ` Erez Zadok
2007-10-25 20:51 ` H. Peter Anvin
2007-10-22 20:01 ` msync(2) bug(?), returns AOP_WRITEPAGE_ACTIVATE to userland Hugh Dickins
2007-10-22 20:40 ` Pekka Enberg
2007-10-22 19:42 ` Hugh Dickins
2007-10-22 21:38 ` Erez Zadok
2007-10-25 18:03 ` Hugh Dickins
2007-10-27 20:47 ` Erez Zadok
2007-10-28 20:23 ` Erez Zadok
2007-10-29 20:33 ` Hugh Dickins
2007-10-31 23:53 ` Erez Zadok
2007-11-05 15:40 ` Hugh Dickins
2007-11-05 16:38 ` Dave Hansen
2007-11-05 18:57 ` Hugh Dickins
2007-11-09 2:47 ` Erez Zadok
2007-11-09 6:05 ` Erez Zadok
2007-11-12 5:41 ` Hugh Dickins
2007-11-12 17:01 ` Hugh Dickins
2007-11-13 10:18 ` Erez Zadok
2007-11-17 21:24 ` Hugh Dickins
2007-11-20 1:30 ` Erez Zadok
-- strict thread matches above, loose matches on Subject: below --
2007-10-07 19:58 Pekka J Enberg
2007-10-08 1:58 ` Ryan Finnie
2007-10-08 11:18 ` Pekka Enberg
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