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From: "H. Peter Anvin" <hpa@transmeta.com>
To: Brian Gerst <bgerst@didntduck.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org
Subject: Re: 2.4.4 kernel reports wrong amount of physical memory
Date: Mon, 14 May 2001 18:46:47 -0700	[thread overview]
Message-ID: <3B008A87.77607AA4@transmeta.com> (raw)
In-Reply-To: <200105142250.f4EMoHt02203@adsl-209-76-109-63.dsl.snfc21.pacbell.net> <Pine.LNX.4.33.0105142025000.18102-100000@duckman.distro.conectiva> <9dpt1e$185$1@cesium.transmeta.com> <3B008D00.A201D690@didntduck.org>

Brian Gerst wrote:
> >
> > It seems obvious once you know why the limits are there.  The 1 GB
> > limit (actually 1024-128 MB = 896 MB) is a software limit; the 4 GB
> > and 64 GB limits are hardware limits and are exact.
> 
> Even with the 4GB and 64GB options, some physical address space has to
> be reserved for memory mapped I/O.
> 

Oh, right.  It's not just virtual address space.  Geez, I'm being really
dense today :)

	-hpa

-- 
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt

      reply	other threads:[~2001-05-15  1:47 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-05-14 19:09 2.4.4 kernel reports wrong amount of physical memory Jeff Golds
2001-05-14 19:29 ` Alan Cox
2001-05-14 20:01 ` Rik van Riel
2001-05-14 22:50   ` Wayne Whitney
2001-05-14 23:25     ` Rik van Riel
2001-05-14 23:39       ` Jeff Golds
2001-05-14 23:41         ` Jeff Golds
2001-05-15  0:44         ` Rik van Riel
2001-05-15  1:00           ` Mohammad A. Haque
2001-05-15  1:07           ` Jeff Golds
2001-05-15  2:32             ` Rik van Riel
2001-05-15  4:19               ` [PATCH] " Wayne Whitney
2001-05-15  0:25       ` H. Peter Anvin
2001-05-15  1:57         ` Brian Gerst
2001-05-15  1:46           ` H. Peter Anvin [this message]

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