From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: Merging kvm-apic into qemu-kvm Date: Thu, 26 Jan 2012 16:25:10 +0100 Message-ID: <4F217056.1030609@siemens.com> References: <4F216E19.3040905@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: KVM list , qemu-devel To: Avi Kivity Return-path: Received: from david.siemens.de ([192.35.17.14]:18462 "EHLO david.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751520Ab2AZPZU (ORCPT ); Thu, 26 Jan 2012 10:25:20 -0500 In-Reply-To: <4F216E19.3040905@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 2012-01-26 16:15, Avi Kivity wrote: > The changes to kvm-apic are so drastic, that merging them into qemu-kvm > in the normal way won't work. I can consider just dropping the existing > implementation and switching to the new one, but the comment at the end > > Make the basic in-kernel irqchip support selectable via > -machine ...,kernel_irqchip=on. Leave it off by default until it can > fully replace user space models. > > suggests that things are still missing. > > Jan, what's still missing? - in-kernel PIT (patches done, waiting for some upstream bits to be merged first) - TPR acceleration via VAPIC (WIP) - MSI support The latter is the big chunk. It requires quite some refactoring/enhancement of the MSI layer. I posted the first version last year. We need to agree on the design, then probably switch qemu-kvm over while pushing generic bits upstream. And then we can extend the upstream in-kernel *PIC using that new interfaces. Once upstream works with MSI, we can switch qemu-kvm over, leaving basically only device-assignment as the last missing bit. > Any idea on how to proceed? I had a qemu-kvm branch here that disables the upstream in-kernel *PIC in favor of its current version. I still need to refresh that work (was based on an earlier revision), but it was not that horrible. Let me check... Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux