From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: Xen 4.3 development update, and stock-taking Date: Thu, 17 Jan 2013 17:11:38 +0000 Message-ID: <50F830CA.4090405@eu.citrix.com> References: <50F7CDBF02000078000B6A95@nat28.tlf.novell.com> <50F7DCA2.1070405@eu.citrix.com> <50F801F102000078000B6CEE@nat28.tlf.novell.com> <50F80378.4070105@eu.citrix.com> <50F815AC02000078000B6DC2@nat28.tlf.novell.com> <50F80B95.3010005@eu.citrix.com> <50F8270902000078000B6E48@nat28.tlf.novell.com> <50F81D33.9030200@eu.citrix.com> <50F8318C02000078000B6ED6@nat28.tlf.novell.com> <50F82705.1000909@eu.citrix.com> <50F839C202000078000B6F3D@nat28.tlf.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <50F839C202000078000B6F3D@nat28.tlf.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich Cc: Konrad Rzeszutek Wilk , "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org On 17/01/13 16:49, Jan Beulich wrote: >> In that case, it would be good if, sometime in the next month or two, >> someone could take a look at exactly what these "quirks" are that Linux >> needs boot services for, and figure out whether we are likely to need >> them. I'll put that in a sort of "call to action", along with any other >> important features not currently on track to make it into 4.3. > I know that code pretty well meanwhile, and I'm unaware of > quirks requiring boot services access. Interesting. Well, maybe I should just ask Colin which changes he was talking about. It's always possible they're in the Ubuntu patchqueue and haven't been upstreamed yet. If it really does have to do with the framebuffer, it might just have to do with the Ubuntu splash screen, which will be replaced once X.org comes up anyway. > Also, I was slightly wrong in saying it is always Linux to exit boot > services: That's the case when booted without boot loader > (i.e. using the EFI_STUB mechanism). Otherwise it's the boot > loader doing so. But you remember that so far we don't really > support booting from EFI with boot loader, so we ought to > always compare ourselves to that stub mechanism. To decide what "Xen has full support for EFI" means, we ought to compare ourselves with anywhere Linux can boot. So if there is some functionality for Ubuntu when booting "EFI -> shim -> bootloader -> Linux", then "full support" means having the same functionality when booting "EFI -> shim -> bootloader -> Xen -> Linux". Not all of that functionality needs to be implemented -- we may decide that "full support" isn't really worth our while (e.g. if it's a lot of work just to make Ubuntu's splash screen function properly instead of falling back to text mode). But it needs to be a conscious decision made for specific reasons, not because we just didn't think about it. -George