From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Tokarev Subject: guest suspend/resume & virtio: vring errors Date: Fri, 08 Jul 2011 23:02:54 +0400 Message-ID: <4E17545E.7010400@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit To: KVM list Return-path: Received: from isrv.corpit.ru ([86.62.121.231]:34194 "EHLO isrv.corpit.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754682Ab1GHTC5 (ORCPT ); Fri, 8 Jul 2011 15:02:57 -0400 Sender: kvm-owner@vger.kernel.org List-ID: I tried suspend/resume cycle for a linux guest today, with 100% failure result. There are 2 possible scenarious after resume (you need pretty recent guest kernel for it to work at all, earlier kernels, incl. early 2.6.32, just stops somewhere at the start of suspend cycle, but 2.6.32.42 and 3.0-rc6 "works"), both are in the same place but different viewpoint. It is either guest complains virtio_net virtio0: input:id 2 is not a head! and enters an endless loop eating 100% CPU, or qemu-kvm exits (aborts) with the message: kvm: Guest moved used index from 1 to 0 this is when trying to use virtio-net. The same happens when disabling network entirely: it complains about virtio-blk in the same way, for example kvm: Guest moved used index from 1 to 49285 qemu-kvm is of version 0.14.1 so far, I'll try a git version later. With e1000 instead of virtio-net-pci, the suspend does not complete - guest kernel freezes after the message "Suspending console(s)" and does not respond (but does not eat 100% CPU either) - the same as for older guest kernel. Has anyone succeeded suspend/resume cycle? Thanks! /mjt