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Date: Tue, 24 Feb 2009 13:59:04 -0800 (PST)
From: Linus Torvalds <torvalds@linux-foundation.org>
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To: Dave Airlie <airlied@redhat.com>
cc: Ingo Molnar <mingo@elte.hu>, Yinghai Lu <yinghai@kernel.org>,
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Subject: Re: [Linux 2.6.29-rc6] [drm:i915_set_status_page] *ERROR* can not
 ioremap virtual address for G33 hw status page
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On Wed, 25 Feb 2009, Dave Airlie wrote:
> > 
> > The other question is, why did the ioremap_wc() fail? Why doesnt 
> > it fall back to UC transparently?
>
> I'm sort of worried the drivers are going to end up doing, which at
> the moment is the only option that will work.
> 
> blah = ioremap_wc();
> if (!blah)
> 	blah = ioremap_nocache();
> 
> which seems pointless so this is a good point, where is the fallback?

I agree.

We should not fail the ioremap_wc(), we should just fall back to nocache, 
(possibly with a warning). In fact I thought we did exactly that, but 
maybe it only happens in certain directions.

			Linus