From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC][PATCH] qemu-kvm: Drop vga dirty logging workarounds Date: Mon, 15 Nov 2010 15:29:46 +0200 Message-ID: <4CE135CA.4060507@redhat.com> References: <4CE10C55.5040104@siemens.com> <4CE132B2.9050507@redhat.com> <4CE1350C.3080304@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:57040 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756409Ab0KON3v (ORCPT ); Mon, 15 Nov 2010 08:29:51 -0500 In-Reply-To: <4CE1350C.3080304@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: On 11/15/2010 03:26 PM, Jan Kiszka wrote: > Am 15.11.2010 14:16, Avi Kivity wrote: > > On 11/15/2010 12:32 PM, Jan Kiszka wrote: > >> These diffs to upstream should all date back to the days qemu-kvm > >> supported vga dirty logging with restricted/broken kvm kernel modules. > >> We no longer do, so there is no need for those workarounds. Even worse > >> they can trigger internal bug checks these days: > >> > >> BUG: kvm_dirty_pages_log_change: invalid parameters 00000000000a8000-00000000000affff > > > > I'd like to apply this. What kind of testing has this seen? autotest > > likely isn't a good enough test. > > No systematic testing. > > It's based on the fact that I'm not aware of any VGA issues in upstream > when KVM is enabled, I don't think upstream+kvm sees a lot of testing. > on the fact that explicit log enable/disable became > obsolete when switching to upstream's logging backend, and the annoying > BUG messages only issued under qemu-kvm. There just remains a slight > uncertainty about what mark_dirty and s[123] were once doing - or may > still be useful for. I remember re-adding some kvm-specific dirty logging code after regressions were uncovered, so I'm a little worried. I guess we can risk it, we can always revert it (or fix) if it turns out badly. -- error compiling committee.c: too many arguments to function