Date: Sun, 16 Nov 2008 00:12:37 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Bernhard Walle <bwalle@suse.de>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH 2/2] Add dev.mem.restricted sysctl
Message-ID: <20081116001237.77e60caf@lxorguk.ukuu.org.uk>
In-Reply-To: <20081116010914.1285b884@kopernikus.site>
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	<20081116010914.1285b884@kopernikus.site>
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> Well, I think that option makes sense to protect the system
> from processes that *accidentally* read/write to the wrong memory
> location (like the X server that always runs as root).

Older X drivers very carefully only map the memory they need. They also
unmap and remap as well as using iopl/ioperm ranges to avoid such
accidents. Newer ones are all DMA command chains and stuff so it won't
make one iota of difference.

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