From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: [PATCHEs]: support more than 32 VCPUs in guests Date: Fri, 16 Jul 2010 18:09:44 -0700 Message-ID: <4C4102D8.3080300@goop.org> References: <20100609160920.1445fbbe@mantra.us.oracle.com> <4C102742.3010108@goop.org> <20100609170825.06a67ff9@mantra.us.oracle.com> <4C1036B0.4060905@goop.org> <20100609191332.588a15d1@mantra.us.oracle.com> <4C15F85A.1050804@goop.org> <20100614194926.2f81ed3d@mantra.us.oracle.com> <4C173A2B.2050701@goop.org> <20100615114543.644442a9@mantra.us.oracle.com> <20100716180613.520ce8bc@mantra.us.oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100716180613.520ce8bc@mantra.us.oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Mukesh Rathor Cc: "Xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 07/16/2010 06:06 PM, Mukesh Rathor wrote: > On Tue, 15 Jun 2010 11:45:43 -0700 > Mukesh Rathor wrote: > > >> On Tue, 15 Jun 2010 09:30:35 +0100 >> Jeremy Fitzhardinge wrote: >> >> >>> On 06/15/2010 03:49 AM, Mukesh Rathor wrote: >>> >>>> On Mon, 14 Jun 2010 10:37:30 +0100 >>>> Jeremy Fitzhardinge wrote: >>>> >>>> >>>> >>>>> On 06/10/2010 03:13 AM, Mukesh Rathor wrote: >>>>> >>>>> >>>>>> Well, BUG_ON is only triggered if booting more than 32 VCPUs on >>>>>> a *very old* xen (pre xen 3.1.0). >>>>>> >>>>>> Looking at code closely, we could just set setup_max_cpus to 32 >>>>>> some where in xen function, perhaps even in xen_vcpu_setup(). >>>>>> That way later in smp_init() it would just be ok. >>>>>> >>>>>> >>>>>> >>>>> Yes. >>>>> >>>>> >>>>> >>>>>> One thing tho, the per cpus areas are already setup at that >>>>>> point, so that would need to be cleaned. BTW, I don't >>>>>> understand why have_vcpu_info_placement is set to 0 in >>>>>> xen_guest_init()? >>>>>> >>>>>> >>>>> xen_guest_init is used by the pvhvm path, and hvm domains don't >>>>> have a notion of vcpu info placement. >>>>> >>>>> >>>>> >>>>>> What minimum version of xen is required to run pvops kernel? >>>>>> >>>>>> >>>>>> >>>>> In theory it should be back-compatible for all Xen 3, but in >>>>> practice it tweaks lots of bugs in older Xens (particularly >>>>> 32-on-64). I don't know that anyone has definitively established >>>>> an earliest version. I implemented vcpu info placement for use >>>>> in pvops kernels, but it was never my intention that it be an >>>>> absolute requirement. >>>>> >>>>> J >>>>> >>>>> >>>> Ok, attached patch without BUG_ON. Please feel free to modify >>>> to your liking also. >>>> >>>> >>> It looks like you smashed all the tabs into spaces so its hard to >>> see what you've changed in the diff. I'll fix it up and give it a >>> look-over. >>> >>> J >>> >> Sorry, I've tabs turned off because patches I submit to other product >> I work on must be tab free. Anyways, re attached a new one with tabs. >> >> thanks again, >> Mukesh >> >> Signed-off-by: Mukesh Rathor >> > Hi Jeremy, > > Just curious, did this patch ever make it? > Probably not. Looks like I forgot to tag it as "mail containing patch" so it fell through the cracks. J