From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC 5/5] KVM: ARM: Access all registers via KVM_GET_ONE_REG/KVM_SET_ONE_REG. Date: Sat, 01 Sep 2012 02:14:24 -0700 Message-ID: <5041D1F0.80406@redhat.com> References: <877gsia8rm.fsf@rustcorp.com.au> <87pq6a8toa.fsf@rustcorp.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Rusty Russell , Alexander Graf , Peter Maydell , kvmarm@lists.cs.columbia.edu, kvm-devel To: Christoffer Dall Return-path: Received: from mx1.redhat.com ([209.132.183.28]:19210 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752500Ab2IAJOf (ORCPT ); Sat, 1 Sep 2012 05:14:35 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 08/29/2012 08:29 AM, Christoffer Dall wrote: > On Tue, Aug 28, 2012 at 4:48 PM, Rusty Russell wrote: > > No structures at all any more. > > > > I fail to see the great benefit of all this. The code is certainly > not easier to read and it's certainly not more clear what is going on. > > Is this simply so we don't have to copy header files into QEMU when > QEMU needs to support a new architecture? We have to do that anyway > no? Do core registers really often change and often we need new > registers for an existing architecture? > > I can see this for cp15 stuff, but core registers? > The nice thing about it is that the hardware vendors can keep adding stuff, and we don't need new ioctls. Just new encodings for register numbers. x86 needed 6-7 updates (some due to our missing some hidden state). -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.