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Subject: Re: [PATCH] ppc64: Add iommu=on for enabling DART on small-mem
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Mike Fedyk <mfedyk@matchmail.com>
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> And maybe even some generic code? :-D

No. It's not possible, at least not at this point. The decision of
allocating the DART space or not (and thus eventually stripping the
max available memory) is done very early. So early that the kernel
isn't yet running at it's link location ;) So the kind of code we
can actually run at this point is limited, with various tweaks to
deal with the relocation issue.

It's not very pretty, I hope we can improve that later, but that
is not something that will happen in the upcoming weeks .

Ben.