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Date: Thu, 17 Apr 2003 13:45:12 -0700
From: Andrew Morton <akpm@digeo.com>
To: Hugh Dickins <hugh@veritas.com>
Cc: rostedt@stny.rr.com, linux-kernel@vger.kernel.org, srostedt@goodmis.org
Subject: Re: What's the reason that /dev/mem can't map unreserved RAM?
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Hugh Dickins <hugh@veritas.com> wrote:
>
> I did start out on eliminating PageReserved a few months ago,
> but was persuaded to delay that until 2.7.  When that's done,
> you will be able to mmap /dev/mem properly.

I think we can almost do it now.  Just a few things like get_user_pages(),
ptrace and core dumping may need to be taught about VM_RESERVED.

Or we could simply change mmap_mem() to set VM_IO if any of the pages aren't
valid.  That's probably an accurate reflection of what the app is trying to
do, too.