From: Alasdair G Kergon <agk@redhat.com>
Subject: Re: [PATCH] Check region size during dirty log creation
Date: Wed, 29 Oct 2008 15:43:57 +0000
Message-ID: <20081029154357.GI31233@agk.fab.redhat.com>
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To: Heinz Mauelshagen <heinzm@redhat.com>
Cc: device-mapper development <dm-devel@redhat.com>
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On Wed, Oct 29, 2008 at 04:07:30PM +0100, Heinz Mauelshagen wrote:
> Am Mittwoch, den 29.10.2008, 13:56 +0000 schrieb Alasdair G Kergon:
> > On Wed, Oct 29, 2008 at 02:02:08PM +0100, Heinz Mauelshagen wrote:
> > The validation should be consistent between userspace and kernel.
> It should be sufficiently restrictive in the kernel to prevent
> programming errors causing oopses. It can be called via the kernel
> interface by any application anyway, so doesn't need to enforce our
> uspace restrictions (think direct IOCTL calls).
 
Surely the validation in the two places should match?
Why would userspace need a tighter restriction than the kernel?
One or the other is incorrect.
- E.g. Does kcopyd handle sub-page regions OK now?

Alasdair
-- 
agk@redhat.com