Hi, I''d read on the Xen FAQ (http://wiki.xensource.com/xenwiki/XenFaq) that Xen can provide certain devices (PCI devices for example), to domains. Does this mean that I can provide my nVidia Graphics card to a domU or would I only be able to use it in dom0? Does it matter if I''m using HVM or a para-virtualized domain? Thanks for your help. -- Mathew Brown mathewbrown@fastmail.fm -- http://www.fastmail.fm - Access your email from home and the web _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Mathew Brown wrote:> Hi, > I''d read on the Xen FAQ (http://wiki.xensource.com/xenwiki/XenFaq) > that Xen can provide certain devices (PCI devices for example), to > domains. Does this mean that I can provide my nVidia Graphics card to > a domU or would I only be able to use it in dom0? Does it matter if > I''m using HVM or a para-virtualized domain? Thanks for your help.Hi Mathew, I tried this last week and was a bit dissapointed when it turned out to be a case of "either/or". I made my graphics card available in a domU with as a result that I lost my dom0 console. I guess you can work around this by redirecting your dom0 console to serial or network, but it isn''t the ideal solution, which would be to make the device shared by both. Maybe something for the future. Sincerely, Jan. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Sun, Oct 22, 2006 at 07:04:01AM -0700, Mathew Brown wrote:> Hi, > I''d read on the Xen FAQ (http://wiki.xensource.com/xenwiki/XenFaq) > that Xen can provide certain devices (PCI devices for example), to > domains. Does this mean that I can provide my nVidia Graphics card to > a domU or would I only be able to use it in dom0? Does it matter if > I''m using HVM or a para-virtualized domain? Thanks for your help.You need an IOMMU to make it work for HVM, which most machine do not have (yet). Cheers, Muli _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Muli Ben-Yehuda wrote:> You need an IOMMU to make it work for HVM, which most machine do not > have (yet).an IOMMU _would_ make it possible; _if_ there was code for managing it, but this code doesn''t exist (yet) or maybe it exists but only in experimental builds... -- Javier _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Sun, Oct 22, 2006 at 12:35:40PM -0500, Javier Guerra wrote:> Muli Ben-Yehuda wrote: > >You need an IOMMU to make it work for HVM, which most machine do not > >have (yet). > > an IOMMU _would_ make it possible; _if_ there was code for managing it, > but this code doesn''t exist (yet)I''m working on IOMMU support but my current focus is para-virtualized guests.> or maybe it exists but only in experimental builds...http://xenbits.xensource.com/ext/xen-iommu.hg http://xenbits.xensource.com/ext/linux-iommu.hg Cheers, Muli _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> -----Original Message----- > From: xen-users-bounces@lists.xensource.com > [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of John Smith > Sent: 22 October 2006 16:20 > To: Mathew Brown > Cc: xen-users@lists.xensource.com > Subject: Re: [Xen-users] Providing a Domain with a Device > > Mathew Brown wrote: > > Hi, > > I''d read on the Xen FAQ (http://wiki.xensource.com/xenwiki/XenFaq) > > that Xen can provide certain devices (PCI devices for example), to > > domains. Does this mean that I can provide my nVidia > Graphics card to > > a domU or would I only be able to use it in dom0? Does > it matter if > > I''m using HVM or a para-virtualized domain? Thanks for your help. > > Hi Mathew, > > I tried this last week and was a bit dissapointed when it turned > out to be a case of "either/or". I made my graphics card > available in a > domU with as a result that I lost my dom0 console. > > I guess you can work around this by redirecting your > dom0 console > to serial or network, but it isn''t the ideal solution, which > would be to > make the device shared by both. Maybe something for the future.Unfortunately, sharing graphics requires extra software somewhere, and the easiest[1] option for this is a para-virtual driver for the DomU. As Muli mentioned, for HVM, it''s necessary to have an IOMMU to allow the graphics card to be "fooled" into thinking that the guest''s memory map is the true memory map. [1] Easiest doesn''t mean easy! Graphics drivers are VERY complex beasts - I worked for a graphics card company a while back, and the driver is tens of megabytes of source-code (roughly the size of the i386 Linux kernel with all the drivers and common-source code, but not as large as ALL the different CPU-flavours that Linux supports). Much of that can probably be "punted" (a Windows term for "let Windows do it through simpler functions"), so in theory you could probably build a small driver that only does simple things - but it would then be slower than if you support direct functionality... If you want a more difficult method of sharing graphics, try writing a cross-domain (with multi-OS support!) cooperative driver - I''ll come visit at the mental institution, ok? ;-) -- Mats> > Sincerely, > > Jan. > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users > > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users