From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH uq/master] kvm: Drop unused kvm_pit_in_kernel Date: Thu, 22 Mar 2012 14:52:36 +0200 Message-ID: <20120322125236.GG22368@redhat.com> References: <4F69CB66.8080903@siemens.com> <4F69D946.3040800@redhat.com> <4F69DA23.8070108@siemens.com> <20120321134157.GT22368@redhat.com> <4F69DC55.3030102@siemens.com> <20120322071827.GW22368@redhat.com> <4F6B1DEE.1020502@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , Marcelo Tosatti , kvm , qemu-devel To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:52825 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754997Ab2CVMwl (ORCPT ); Thu, 22 Mar 2012 08:52:41 -0400 Content-Disposition: inline In-Reply-To: <4F6B1DEE.1020502@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Mar 22, 2012 at 01:41:18PM +0100, Jan Kiszka wrote: > On 2012-03-22 08:18, Gleb Natapov wrote: > > On Wed, Mar 21, 2012 at 02:49:09PM +0100, Jan Kiszka wrote: > >> On 2012-03-21 14:41, Gleb Natapov wrote: > >>> On Wed, Mar 21, 2012 at 02:39:47PM +0100, Jan Kiszka wrote: > >>>> On 2012-03-21 14:36, Avi Kivity wrote: > >>>>> On 03/21/2012 02:36 PM, Jan Kiszka wrote: > >>>>>> This is now implied by kvm_irqchip_in_kernel. > >>>>>> > >>>>>> > >>>>> > >>>>> So we can't have -no-kvm-pit? > >>>>> > >>>>> No huge loss, but unexpected. > >>>> > >>>> See e81dda195556e72f8cd294998296c1051aab30a8. > >>>> > >>> I am curious what is the reason for upstream to not supporting disabling the > >>> in-kernel PIT separately? > >> > >> It was considered no longer relevant: > >> http://thread.gmane.org/gmane.comp.emulators.kvm.devel/85393 > >> > > Hmm, may be we should think about this some more. If in the (not so far) > > future we want to drop pit emulation from the kernel we may want to support > > -no-kvm-pit to allow migration from old kernels to new one. > > That's not an issue. Both device models are compatible, and you can > migrate between kernel_irqchip=on/off theses days with QEMU. > Cool. Including PIT lost tick compensation? -- Gleb.