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From:   David Howells <dhowells@redhat.com>
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To:     Randy Dunlap <rdunlap@infradead.org>
Cc:     dhowells@redhat.com, torvalds@linux-foundation.org,
        linux-man@vger.kernel.org, linux-api@vger.kernel.org,
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Subject: Re: [PATCH 01/24] Add the ability to lock down access to the running kernel image
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Date:   Wed, 11 Apr 2018 18:49:05 +0100
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Randy Dunlap <rdunlap@infradead.org> wrote:

> > +	  drivers from functioning because allowing manual configuration of
> > +	  hardware parameters is forbidden, lest a device be used to access the
> > +	  kernel by DMA.  This mostly applies to ISA devices.
> 
> 	Is DMA from non-ISA devices OK, or did I miss seeing that patch?

The issue is where you can directly command a device to do DMA, possibly by
using the wrong driver.  Ask Alan Cox.

David