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From: David Howells <dhowells@redhat.com>
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References: <376.1132773809@warthog.cambridge.redhat.com>  <Pine.LNX.4.64.0511231109040.13959@g5.osdl.org> <dhowells1132772387@warthog.cambridge.redhat.com> 
To: David Howells <dhowells@redhat.com>
Cc: Linus Torvalds <torvalds@osdl.org>, akpm@osdl.org, dalomar@serrasold.com,
       linux-kernel@vger.kernel.org, uclinux-dev@uclinux.org
Subject: Re: [PATCH 1/3] NOMMU: Provide shared-writable mmap support on ramfs 
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Date: Wed, 23 Nov 2005 19:25:18 +0000
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David Howells <dhowells@redhat.com> wrote:

> > Truncate is _supposed_ to get rid of any shared mmap stuff. 
> 
> Yeah... but under _NOMMU_ conditions, it can't. There's no MMU around to
> enforce the fact that the mapping has been shrunk.

I may not have mentioned, but this does not apply under MMU conditions. A
different file in fs/ramfs/ swings into action and does the normal thing.

David