From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: ATI radeon fails with "iommu=soft swiotlb=force" (seen on RV730/RV740 and RS780/RS800) Date: Tue, 06 Oct 2009 12:01:31 -0700 Message-ID: <4ACB940B.3050009@goop.org> References: <41093.83224.qm@web56108.mail.re3.yahoo.com> <4AC649B0.5090700@goop.org> <4AC9E75F0200007800017F61@vpn.id2.novell.com> <4ACA4459.4000903@goop.org> <4ACB177C0200007800018277@vpn.id2.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4ACB177C0200007800018277@vpn.id2.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jan Beulich Cc: dri-devel@lists.sourceforge.net, xen-devel@lists.xensource.com, Konrad Rzeszutek Wilk List-Id: xen-devel@lists.xenproject.org On 10/06/09 01:10, Jan Beulich wrote: >>>> Jeremy Fitzhardinge 05.10.09 21:09 >>> >>>> >> vmalloc_32 is a general problem. The only clean way I can see to make >> it work under Xen is to make sure all the pages in the DMA32 zone are >> really under 4G in machine addresses. But that doesn't scale very well >> > Why? Just adding a hook in vmalloc.c would do. > Yeah, but I'm a bit allergic to suggesting new hooks. > Hmm, yes, but the more cumbersome an API is to use, the less likely it > is that people would want to adopt using it (or that it would be mergable > in the first place)). > It would need a somewhat detailed survey to work out how many drivers would be affected, and some input from other arch/iommu people to see if it is at all helpful to them. J