From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: should KVM or userspace be the one which decides what MIPIDR/affinity values to assign to vcpus? Date: Thu, 25 Jun 2015 14:41:13 +0200 Message-ID: <20150625124113.GF28244@cbox> References: <5576C559.2000902@arm.com> <20150625080014.GC28244@cbox> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org To: Peter Maydell Cc: Marc Zyngier , Shlomo Pongratz , Shlomo Pongratz , Pavel Fedin , QEMU Developers , Shannon Zhao , Ashok Kumar , Igor Mammedov , "kvmarm@lists.cs.columbia.edu" List-Id: kvmarm@lists.cs.columbia.edu On Thu, Jun 25, 2015 at 10:06:20AM +0100, Peter Maydell wrote: > On 25 June 2015 at 09:00, Christoffer Dall wrote: > > Of course, KVM can deny an unsupported configuration, but I am wondering > > if we really think anybody will care about the 'model such specific > > hardware' aspect with KVM, or if we should only consider the 'I want a > > VM with x VCPUs' scenario, in which case the second option below seems > > simpler to me. > > I agree it's not very likely anybody cares about the specific cluster > topology. However if we don't want to support arbitrary topologies > then QEMU is going to end up in the business of editing the user > supplied device tree blob to make its cpu definitions match up with > whatever the kernel provides, which could be pretty tedious. > I see, then you can't easily contruct a machine and a DT in one go before talking to KVM. Oh well, I don't feel strongly one way or the other. -Christoffer