From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: Bugs in kvm guest migration Date: Fri, 04 Dec 2009 14:25:28 +0100 Message-ID: <4B190DC8.60005@siemens.com> References: <4B17DB29.9060801@siemens.com> <4B181033.1020804@siemens.com> <4B18C176.7050105@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm , qemu-devel To: Avi Kivity Return-path: Received: from thoth.sbs.de ([192.35.17.2]:21010 "EHLO thoth.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756363AbZLDNZq (ORCPT ); Fri, 4 Dec 2009 08:25:46 -0500 In-Reply-To: <4B18C176.7050105@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Avi Kivity wrote: > On 12/03/2009 09:23 PM, Jan Kiszka wrote: >> Jan Kiszka wrote: >> >>> Problem 2 >>> --------- >>> Setup: qemu head with vmstate fixes. kvm-kmod master, 64-bit host& guest. >>> Effect: The migration target either locks up or reboots immediately. >>> I've nailed this down to 84d0b66c778d881eafca2a5d0d66678211c4e861. Every >>> kvm module build before that works, everything including and after >>> 26ede77f536d1bb369527a96c7fe7fdc8ba2f890 shows the effect (everything in >>> between crashes the host for known reasons). It's still unclear if this >>> is an kvm-kmod wrapping issue of the user-space return notifiers. Will >>> check once problem #1 is understood. >>> >> It is kernel-related, using kvm.git as host kernel makes no difference. >> >> This may now mean that kvm is buggy or that it triggers some msr >> save/restore related issues in qemu. Digging even deeper... >> > > Does calling drop_user_return_notifiers() (static in x86.c, will need > exporting) in vmx_load_host_state() within the preempt-disable region help? > Nope. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux