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From: Lev Makhlis <mlev@despammed.com>
To: "Andi Kleen" <ak@muc.de>, "Michael Brown" <mebrown@michaels-house.net>
Subject: Re: [PATCH 2.4] add SMBIOS information to /proc/smbios -- UPDATED
Date: Sat, 1 May 2004 16:00:44 -0500
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> > -- This information is, in the very near future, _not_ going to be
> > static anymore. There will be systems that update the information in
> > dynamically during SMIs.
>
> That's fine - /dev/mem can handle that too. An user will have to
> poll for changes anyways, so having it it /proc does not have
> any advantages.

One problem is that /dev/mem access isn't atomic.  You need to read
a pointer, then follow the pointer to read data.  If the pointer changes
in the middle, you lose.  That said, I don't see any mechanism that
helps avoid that in kernel, either.