From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Egger Subject: Re: [PATCH][XEN] PV blk backend: Make 32bit PV guests work on 64bit PV Dom0 Date: Mon, 28 Jul 2008 14:31:33 +0200 Message-ID: <200807281431.33730.Christoph.Egger@amd.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: 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: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Monday 28 July 2008 14:23:00 Keir Fraser wrote: > Just do the same as we do in Linux and put these defs in your NetBSD > private header space. That sounds like "All OS's have to go the Linux way" (which also includes Xen's Minios (stubdom)) instead of "fix it once and for all". Christoph > > -- Keir > > On 28/7/08 12:46, "Christoph Egger" wrote: > > Hi, > > > > Attached patch makes the PV block driver for 32bit PV guests working on > > 64bit PV Dom0. > > > > In the io/blkif.h, the 'id' field of > > struct blkif_request is 64bit, but on a LP32 system it's aligned on > > 32bits, while it'll be aligned to 64bits on a LP64 system. So on LP64 > > there'll be 4 bytes of padding between handle and id. The same is true > > for struct blkif_response: it's 11 bytes long, so will be aligned > > differently in the ring between a 32 and 64bit systems. > > > > In order to fix this, attached patch introduces in the public headers, > > blkif_request/blkif_response, blkif_x86_32_request/blkif_x86_32_response > > and blkif_x86_64_request/blkif_x86_64_response. > > NetBSD is doing so io/blkif.h in the public headers, while Linux > > does so in include/xen/blkif.h in the linux sources. But the result is > > the same ... > > > > Successfully tested with the combinations: > > > > 64bit Dom0 32bit PAE PV guest > > NetBSD Linux > > Linux NetBSD > > > > The combinations 64bit Dom0, 64bit PV DomU works with and without this > > patch. > > > > Signed-off-by: Christoph Egger =2D-=20 AMD Saxony, Dresden, Germany Operating System Research Center Legal Information: AMD Saxony Limited Liability Company & Co. KG Sitz (Gesch=E4ftsanschrift): Wilschdorfer Landstr. 101, 01109 Dresden, Deutschland Registergericht Dresden: HRA 4896 vertretungsberechtigter Komplement=E4r: AMD Saxony LLC (Sitz Wilmington, Delaware, USA) Gesch=E4ftsf=FChrer der AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy