From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Huang Subject: Re: RE: [RFC][QEMU] ATI graphics VBIOS passthru support Date: Fri, 17 Dec 2010 01:03:14 -0600 Message-ID: <1292569394.1958.11.camel@weilaptop> References: <296687315.20101213211746@eikelenboom.it> <20101216182940.GW2754@reaktio.net> Reply-To: wei.huang2@amd.com Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20101216182940.GW2754@reaktio.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Pasi =?ISO-8859-1?Q?K=E4rkk=E4inen?= Cc: Xen-devel , Keir Fraser , Jackson , "Kay, Allen M" , "Wang2, Wei" , Sander Eikelenboom , "djmagee@mageenet.net" , "Ian@ikuisesti.iki.fi" List-Id: xen-devel@lists.xenproject.org Hi Pasi, Users can do it in setup_vga_pt() in pt-graphics.c with something like: + int fd; + fd =3D open("/tmp/downloaded_vbios.bin", O_RDONLY); + bios_size =3D read(fd, bios, bios_size); + close(fd); Then we can pass bios_size and bios to cpu_physical_memory_rw() function. -Wei On Thu, 2010-12-16 at 12:29 -0600, Pasi K=C3=A4rkk=C3=A4inen wrote: > On Mon, Dec 13, 2010 at 02:33:02PM -0600, Huang2, Wei wrote: > > Hi Sander, > > > > I answer your questions (including the one from last email) below: > > > > 1. Your gfx is a bit old. Some of the tricks (such as MMINDEX values = 0x4010) aren't quite consistent across different generations of ATI gfx. = I need to look at the log myself. I will locate an HD3000 card to debug. > > 2. The goal of this patch is to passthru the primary gfx as THE ONLY = GFX inside guest VM (namely: my patch + set gfx_passthru=3D1 in guest con= fig file). Since you are passthru the on-board secondary gfx, I am not su= re qemu-dm is copying the correct VBIOS from address 0xc0000. One solutio= n is to force VBIOS been read from a file, which can be downloaded from h= ttp://www.techpowerup.com/vgabios/. > > >=20 > Do you happen to have a patch that allows specifying the file to load t= he vga bios > from in the xen /etc/xen/ cfgfile ? >=20 > That'd be helpful for the time being.. >=20 > -- Pasi >=20 > > 3. Note that current Xen support passthru ATI gfx as a secondary gfx,= even without my patch. So if you don't care about primary/secondary, you= probably don't need this patch. Have you tried: existing Xen + passthru = ATI without gfx_passthru=3D1? As for as I have seen, it worked for many A= TI gfx. > > > > Thanks, > > -Wei > > > > -----Original Message----- > > From: Sander Eikelenboom [mailto:linux@eikelenboom.it] > > Sent: Monday, December 13, 2010 2:18 PM > > To: Huang2, Wei > > Cc: Keir Fraser; Xen-devel; Ian Jackson; Kay, Allen M; Wang2, Wei; dj= magee@mageenet.net > > Subject: Re: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS passthru = support > > > > Hello Wei, > > > > It just occured to me, this is probably only working when trying to p= assthrough the primary graphics card ? > > I'm trying to passthrough a secondary card, so the primary(boot) card= still has the xen/dom0 console. > > > > It could end up giving problems by loading the wrong/no bios in the h= vmloader ? > > > > Should passing though a secondary graphics card also be possible with= this patch ? > > > > -- > > Sander > > > > Sunday, December 12, 2010, 7:19:08 AM, you wrote: > > > > > This patch isn't meant to be final version. The stubdom issue was k= nown to me. Users can just compile qemu-dm and copy it to overwrite exist= ing Xen installation for a quick testing. > > > > > Thanks, > > > -Wei > > > ________________________________________ > > > From: Keir Fraser [keir.xen@gmail.com] On Behalf Of Keir Fraser [ke= ir@xen.org] > > > Sent: Saturday, December 11, 2010 9:38 AM > > > To: Sander Eikelenboom; Huang2, Wei > > > Cc: Xen-devel; Ian Jackson; Kay, Allen M; Wang2, Wei; djmagee@magee= net.net > > > Subject: Re: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS passthr= u support > > > > > The patch would need some work to make it suitable for check in and= get it > > > working for stubdom. At the very least the ioperm() calls would nee= d > > > removing completely, or stubbing out for the stubdom build. > > > > > -- Keir > > > > > On 11/12/2010 14:06, "Sander Eikelenboom" wr= ote: > > > > >> Do i need any previous patches for this to work ? > > >> > > >> After applying it to xen-unstable, compiling xen results in: > > >> > > >> make[2]: Entering directory `/usr/src/new/xen-unstable.hg/extras/m= ini-os' > > >> [ -e include/xen ] || ln -sf ../../../xen/include/public include/x= en > > >> [ -e include/mini-os ] || ln -sf . include/mini-os > > >> [ -e include/x86/mini-os ] || ln -sf . include/x86/mini-os > > >> make --directory=3Darch/x86 > > >> OBJ_DIR=3D/usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioem= u/arch/x86 || > > >> exit 1; > > >> make[3]: Entering directory > > >> `/usr/src/new/xen-unstable.hg/extras/mini-os/arch/x86' > > >> make[3]: Nothing to be done for `all'. > > >> make[3]: Leaving directory > > >> `/usr/src/new/xen-unstable.hg/extras/mini-os/arch/x86' > > >> ld -r -nostdlib > > >> -L/usr/src/new/xen-unstable.hg/stubdom/cross-root-x86_64/x86_64-xe= n-elf/lib > > >> -m elf_x86_64 > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/arch/x86= /x86_64.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os_= app.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/blkfront= .o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/events.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/fbfront.= o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/fs-front= .o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/gntmap.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/gnttab.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/hypervis= or.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/kernel.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lock.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/main.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mm.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/netfront= .o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/pcifront= .o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/sched.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/ctyp= e.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/math= .o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/prin= tf.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/stac= k_chk_fail.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/stri= ng.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/sys.= o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/xmal= loc.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lib/xs.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/xenbus/x= enbus.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/console/= console.o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/console/= xencons_ring > > >> .o /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/lwip.= a > > >> -L/usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/arch/x= 86 -lx86_64 > > >> -lc -o /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/m= ini-os.o > > >> objcopy -w -G xenos_* -G _start > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os.= o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os.= o > > >> ld -nostdlib > > >> -L/usr/src/new/xen-unstable.hg/stubdom/cross-root-x86_64/x86_64-xe= n-elf/lib > > >> -m elf_x86_64 -T arch/x86/minios-x86_64.lds > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os.= o -o > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os.= o: In > > >> function `ati_hw_out': > > >> /usr/src/new/xen-unstable.hg/stubdom/ioemu/hw/pt-graphics.c:82: un= defined > > >> reference to `ioperm' > > >> /usr/src/new/xen-unstable.hg/stubdom/ioemu/hw/pt-graphics.c:84: un= defined > > >> reference to `ioperm' > > >> /usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os.= o: In > > >> function `ati_hw_in': > > >> /usr/src/new/xen-unstable.hg/stubdom/ioemu/hw/pt-graphics.c:72: un= defined > > >> reference to `ioperm' > > >> /usr/src/new/xen-unstable.hg/stubdom/ioemu/hw/pt-graphics.c:74: un= defined > > >> reference to `ioperm' > > >> make[2]: *** > > >> [/usr/src/new/xen-unstable.hg/stubdom/mini-os-x86_64-ioemu/mini-os= ] Error 1 > > >> make[2]: Leaving directory `/usr/src/new/xen-unstable.hg/extras/mi= ni-os' > > >> make[1]: *** [ioemu-stubdom] Error 2 > > >> make[1]: Leaving directory `/usr/src/new/xen-unstable.hg/stubdom' > > >> make: *** [install-stubdom] Error 2 > > >> > > >> Don't know why the include of sys/io.h doesn't seem to work > > >> -- > > >> > > >> Sander > > >> > > >> Saturday, December 11, 2010, 12:40:19 AM, you wrote: > > >> > > >>> Hi, > > >> > > >>> The attached patch supports dynamic detection of BARs (both MMIO = and > > >>> PIO). Hopefully it can alleviate some of the issues you saw with = ATI gfx > > >>> passthru. Please let me know whether it works better for you. > > >> > > >>> Thanks, > > >>> -Wei > > >> > > >>> On 12/07/2010 04:00 AM, Pasi K=C3=A4rkk=C3=A4inen wrote: > > >>>> On Wed, Oct 13, 2010 at 04:37:10PM -0500, Huang2, Wei wrote: > > >>>>> Sorry, hold on a second. This fix seems corrupt my pci conf= ig space > > >>>>> after > > >>>>> several runs. > > >>>>> > > >>>> Hello, > > >>>> > > >>>> Any updates to these patches? Many users have been asking about = amd/ati vga > > >>>> passthru stuff.. > > >>>> > > >>>> -- Pasi > > >>>> > > >>>>> > > >>>>> -Wei > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: xen-devel-bounces@lists.xensource.com > > >>>>> [mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of= Huang2, Wei > > >>>>> Sent: Wednesday, October 13, 2010 3:47 PM > > >>>>> To: djmagee@mageenet.net; Kay, Allen M; Ian Jackson > > >>>>> Cc: Wang2, Wei; Xen-devel > > >>>>> Subject: RE: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS= passthru > > >>>>> support > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Allen and Doug, > > >>>>> > > >>>>> > > >>>>> > > >>>>> Could you fix the following line in save_pci_conf_space() o= f > > >>>>> tools/python/xen/util/pci.py? > > >>>>> > > >>>>> > > >>>>> > > >>>>> "for i in range(0, 256, 4):" to "for i in range(0, = 512, 4):" > > >>>>> > > >>>>> > > >>>>> > > >>>>> This solves my black screen issue. Please let me know the r= esults. > > >>>>> > > >>>>> > > >>>>> > > >>>>> > > >>>>> > > >>>>> Thanks, > > >>>>> > > >>>>> -Wei > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: djmagee@mageenet.net [mailto:djmagee@mageenet.net] > > >>>>> Sent: Friday, October 08, 2010 10:53 AM > > >>>>> To: Huang2, Wei; Kay, Allen M; Ian Jackson > > >>>>> Cc: Xen-devel; Wang2, Wei > > >>>>> Subject: RE: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS= passthru > > >>>>> support > > >>>>> > > >>>>> > > >>>>> > > >>>>> Wei, > > >>>>> > > >>>>> These were guests that had never seen the c= atalyst > > >>>>> driver > > >>>>> before. I booted each three with the graphics device and u= sb devices > > >>>>> assigned, they worked fine using the basic VGA driver, then= installed > > >>>>> fresh Catalyst 10.9, rebooted, and each one crashed. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Let me know if there's any other info I can= provide > > >>>>> that > > >>>>> will help you debug. The motherboard is a DQ45CB, running = xen-unstable > > >>>>> c/s 22155 using `dom0_mem=3D768M iommu=3D1' on the grub lin= e, and using > > >>>>> pvops > > >>>>> Dom0 from stable-2.6.32.x commit 179eca50. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Doug Magee > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: Huang2, Wei [mailto:Wei.Huang2@amd.com] > > >>>>> Sent: Friday, October 08, 2010 11:41 AM > > >>>>> To: djmagee@mageenet.net; Kay, Allen M; Ian Jackson > > >>>>> Cc: Xen-devel; Wang2, Wei > > >>>>> Subject: RE: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS= passthru > > >>>>> support > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Doug, > > >>>>> > > >>>>> > > >>>>> > > >>>>> Regarding Catalyst driver, we never saw guest crashing. Was= it a fresh > > >>>>> Catalyst installation or an existing guest image? We felt t= his VBIOS > > >>>>> patch > > >>>>> might not provide all necessary resources to driver, which = got upset. > > >>>>> Currently we are debugging it with our driver team and will= let you > > >>>>> know > > >>>>> the update. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Thanks, > > >>>>> > > >>>>> -Wei > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: djmagee@mageenet.net [mailto:djmagee@mageenet.net] > > >>>>> Sent: Friday, October 08, 2010 9:41 AM > > >>>>> To: Huang2, Wei; Kay, Allen M; Ian Jackson > > >>>>> Cc: Xen-devel > > >>>>> Subject: RE: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS= passthru > > >>>>> support > > >>>>> > > >>>>> > > >>>>> > > >>>>> Wei, > > >>>>> > > >>>>> I've tested with a Radeon 4770 and it the V= BIOS works > > >>>>> without a problem, through many guest (re)boots, so it seem= s pretty > > >>>>> solid. I tested a linux guest (fairly standard Fedora 12),= Windows XP, > > >>>>> and Windows 7 (without accelerated drivers). The open rade= on linux > > >>>>> driver > > >>>>> works fine. > > >>>>> > > >>>>> > > >>>>> > > >>>>> The Catalyst driver fails in Windows XP (STOP 0x000000EA, t= hread stuck > > >>>>> in > > >>>>> device driver), windows 7 (STOP 0x00000116, driver fails to= properly > > >>>>> reset?), and linux (total system freeze). This seems to be= different > > >>>>> than > > >>>>> the `Blank Screen' problem you report, as the driver is cle= arly not > > >>>>> functioning properly. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Doug Magee > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: xen-devel-bounces@lists.xensource.com > > >>>>> [mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of= Huang2, Wei > > >>>>> Sent: Friday, October 08, 2010 9:57 AM > > >>>>> To: Kay, Allen M; Ian Jackson > > >>>>> Cc: Xen-devel > > >>>>> Subject: [Xen-devel] RE: [RFC][QEMU] ATI graphics VBIOS pas= sthru > > >>>>> support > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Allen, > > >>>>> > > >>>>> > > >>>>> > > >>>>> Yes, Catalyst driver is the one from public website. The dr= iver still > > >>>>> has > > >>>>> a minor issue with this VBIOS patch. The purpose of submit= ting VBIOS > > >>>>> patch is to get community feedbacks. After we figure out th= e root cause > > >>>>> of > > >>>>> black screen, I will formally submit a patch for inclusion. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Thanks, > > >>>>> > > >>>>> -Wei > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: Kay, Allen M [mailto:allen.m.kay@intel.com] > > >>>>> Sent: Friday, October 08, 2010 2:21 AM > > >>>>> To: Huang2, Wei; Ian Jackson > > >>>>> Cc: Xen-devel > > >>>>> Subject: RE: [RFC][QEMU] ATI graphics VBIOS passthru suppor= t > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Wei, > > >>>>> > > >>>>> > > >>>>> > > >>>>> Is Catalyst driver the one on AMD website? I think that's = what I have > > >>>>> in > > >>>>> my win7 guest and it matches the symptom you are describing= . "lspci" > > >>>>> reports my ATI card is a V5700 - although it says v3750 on = the box. > > >>>>> Where > > >>>>> can I get a working driver? > > >>>>> > > >>>>> > > >>>>> > > >>>>> The patch looks reasonable to me in general. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Allen > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: Huang2, Wei [mailto:Wei.Huang2@amd.com] > > >>>>> Sent: Thursday, October 07, 2010 9:06 PM > > >>>>> To: Kay, Allen M; Ian Jackson > > >>>>> Cc: Xen-devel > > >>>>> Subject: RE: [RFC][QEMU] ATI graphics VBIOS passthru suppor= t > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Allen, > > >>>>> > > >>>>> > > >>>>> > > >>>>> Thanks for testing it out. We have tested this patch with R= adeon 4850, > > >>>>> 4870, FirePro V5700 and FirePro M5800. Unfortunately we don= 't have > > >>>>> V3750 > > >>>>> at hand. It is very possible this patch isn't compatible wi= th V3750. We > > >>>>> will try to get hold of one for debugging. For graphics whi= ch work with > > >>>>> this path, users should be able to get rid of emulated gfx = (such as > > >>>>> Cirrus). I have successfully installed a Windows guest VM u= sing this > > >>>>> patch. > > >>>>> > > >>>>> > > >>>>> > > >>>>> I also want to point out that there is still an issue. User= s will see a > > >>>>> black screen after installing Catalyst driver. Even though = the screen > > >>>>> appears to be black, the driver is actually functioning cor= rectly > > >>>>> (3DMark > > >>>>> can be run with external monitor). Our driver team is curre= ntly > > >>>>> debugging > > >>>>> it and they believe this is easy to fix. > > >>>>> > > >>>>> > > >>>>> > > >>>>> What is your opinion on this patch (and the solution) in ge= neral? > > >>>>> > > >>>>> > > >>>>> > > >>>>> -Wei > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: Kay, Allen M [mailto:allen.m.kay@intel.com] > > >>>>> Sent: Thursday, October 07, 2010 6:58 PM > > >>>>> To: Huang2, Wei; Ian Jackson > > >>>>> Cc: Xen-devel > > >>>>> Subject: RE: [RFC][QEMU] ATI graphics VBIOS passthru suppor= t > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Wei, > > >>>>> > > >>>>> > > >>>>> > > >>>>> This patch did not cause any problems with Intel IGD passth= rough for > > >>>>> me. > > >>>>> However, the monitor remained blank if I pass through ATI F= irepro V3750 > > >>>>> either as the primary display device or the secondary devic= e > > >>>>> (gfx_passthru=3D1/0). Passing it through as the secondary = device used to > > >>>>> work. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Have you tested the patch with this graphics card? > > >>>>> > > >>>>> > > >>>>> > > >>>>> Allen > > >>>>> > > >>>>> > > >>>>> > > >>>>> From: Huang2, Wei [mailto:Wei.Huang2@amd.com] > > >>>>> Sent: Thursday, October 07, 2010 9:57 AM > > >>>>> To: Ian Jackson > > >>>>> Cc: Xen-devel; Kay, Allen M > > >>>>> Subject: [RFC][QEMU] ATI graphics VBIOS passthru support > > >>>>> > > >>>>> > > >>>>> > > >>>>> Hi Ian, > > >>>>> > > >>>>> > > >>>>> > > >>>>> There have been a lot of interest on gfx passthru recently.= This patch > > >>>>> enables ATI VBIOS in passthru mode. The guest VM system BIO= S (including > > >>>>> Windows boot logo) can now show in passthru screen. We have= tested with > > >>>>> various Windows and Linux guest VMs. Please help review it.= We are also > > >>>>> looking forward to comments and suggestions from Xen commun= ity users. > > >>>>> > > >>>>> > > >>>>> > > >>>>> Signed-off-by: Wei Huang > > >>>>> > > >>>>> Signed-off-by: Wei Wang > > >>>>> > > >>>>> > > >>>>> > > >>>>> > > >>>>> _______________________________________________ > > >>>>> Xen-devel mailing list > > >>>>> Xen-devel@lists.xensource.com > > >>>>> http://lists.xensource.com/xen-devel > > >>>> > > >> > > >> > > >> > > > > > > > > > > > > > > > > -- > > Best regards, > > Sander mailto:linux@eikelenboom.it > > > > > > > > > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@lists.xensource.com > > http://lists.xensource.com/xen-devel >=20