From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: qemu-kvm upstreaming: Do we need -no-kvm-pit and -no-kvm-pit-reinjection semantics? Date: Thu, 19 Jan 2012 09:33:51 +0100 Message-ID: <4F17D56F.9090309@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: qemu-devel To: kvm Return-path: Received: from goliath.siemens.de ([192.35.17.28]:21811 "EHLO goliath.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752873Ab2ASIeb (ORCPT ); Thu, 19 Jan 2012 03:34:31 -0500 Sender: kvm-owner@vger.kernel.org List-ID: Hi all, I've finished a first version of cleaned-up in-kernel KVM PIT support. That will be rolled out once the base support for irqchip has been merged. I'm now wondering if and how to model two control knobs we have in qemu-kvm: o -no-kvm-pit, ie. disable the in-kernel PIT even when {A,IOA,}PIC are kernel based (default: off, ie. use in-kernel PIT) o -no-kvm-pit-reinjection, ie. control over the lost ticks reinjection logic in the kernel (default: off, ie. do reinject) So far I dropped the former and modeled the latter via a qdev property. But I tend to think that even the latter knob is superfluous. In that case I would also deprecate the original switches in qemu-kvm, just like recently done with -tdf. Other thoughts? Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux