From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: bus_to_virt() Date: Thu, 05 Jul 2007 11:04:07 +0100 Message-ID: <468CDE37.76E4.0078.0@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Isn't it inappropriate for bus_to_virt() to use, through machine_to_phys(),= mfn_to_pfn() rather than mfn_to_local_pfn()? If a foreign domain's address gets uses here, the virtual address returned might be anything. I'm specifically asking because I finally want to make an attempt to (a) merge our swiotlb.c up with native's lib/swiotlb.c and then (b) move ours to lib/swiotlb-xen.c. Native, however, uses a virtual address range check, = and hence the bus_to_virt() return value must reliable. If changing the macro globally isn't appropriate (I can't see what valid uses there might be for = this macro with non-local addresses, hence a change like this would be benign = to all other users), I'd have to hand-craft a mechanism local to swiotlb.c to = that I can keep the delta to native down. Thanks, Jan