From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: (v2) Design proposal for RMRR fix Date: Mon, 12 Jan 2015 12:23:12 +0000 Message-ID: <1421065392.26317.21.camel@citrix.com> References: <54AE9A2F0200007800052ACF@mail.emea.novell.com> <54AFAB90020000780005303C@mail.emea.novell.com> <54AFBCE502000078000530F3@mail.emea.novell.com> <54B3A2D602000078000538A2@mail.emea.novell.com> <54B3A71002000078000538E1@mail.emea.novell.com> <54B3AB380200007800053917@mail.emea.novell.com> <54B3AE8802000078000539B7@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: George Dunlap Cc: "Tian, Kevin" , "wei.liu2@citrix.com" , "stefano.stabellini@eu.citrix.com" , "ian.jackson@eu.citrix.com" , "tim@xen.org" , "xen-devel@lists.xen.org" , Jan Beulich , "Zhang, Yang Z" , "Chen, Tiejun" List-Id: xen-devel@lists.xenproject.org On Mon, 2015-01-12 at 12:13 +0000, George Dunlap wrote: > On Mon, Jan 12, 2015 at 11:22 AM, Tian, Kevin wrote: > >> From: Jan Beulich [mailto:JBeulich@suse.com] > >> Sent: Monday, January 12, 2015 6:23 PM > >> > >> >>> On 12.01.15 at 11:12, wrote: > >> >> From: Jan Beulich [mailto:JBeulich@suse.com] > >> >> Sent: Monday, January 12, 2015 6:09 PM > >> >> > >> >> >>> On 12.01.15 at 10:56, wrote: > >> >> > the result is related to another open whether we want to block guest > >> >> > boot for such problem. If 'warn' in domain builder is acceptable, we > >> >> > don't need to change lowmem for such rare 1GB case, just throws > >> >> > a warning for unnecessary conflictions (doesn't hurt if user doesn't > >> >> > assign it). > >> >> > >> >> And how would you then deal with the one guest needing that > >> >> range reserved? > >> > > >> > if guest needs the range, then report-all or report-sel doesn't matter. > >> > domain builder throws the warning, and later device assignment will > >> > fail (or warn w/ override). In reality I think 1GB is rare. Making such > >> > assumption to simplify implementation is reasonable. > >> > >> One of my main problems with all you recent argumentation here > >> is the arbitrary use of the 1Gb boundary - there's nothing special > >> in this discussion with where the boundary is. Everything revolves > >> around the (undue) effect of report-all on domains not needing all > >> of the ranges found on the host. > >> > > > > I'm not sure which part of my argument is not clear here. report-all > > would be a problem here only if we want to fix all the conflictions > > (then pulling unnecessary devices increases the confliction possibility) > > in the domain builder. but if we only fix reasonable ones (e.g. >3GB) > > while warn other conflictions (e.g. <3G) in domain builder (let later > > assignment path to actually fail if confliction does matter), then we > > don't need to solve all conflictions in domain builder (if say 1G example > > fixing it may instead reduce lowmem greatly) and then report-all > > may just add more warnings than report-sel for unused devices. > > You keep saying "report-all" or "report-sel", but I'm not 100% clear > what you mean by those. Is the distinction between "all reserved areas" and "only (selectively) those which are related to an RMRR"? That's how I've been reading it... Ian.