From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43543) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WRToD-0006Bt-KJ for qemu-devel@nongnu.org; Sat, 22 Mar 2014 17:50:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WRTo7-0002LO-Cv for qemu-devel@nongnu.org; Sat, 22 Mar 2014 17:50:29 -0400 Received: from mail-pd0-f174.google.com ([209.85.192.174]:62107) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WRTo7-0002Jz-88 for qemu-devel@nongnu.org; Sat, 22 Mar 2014 17:50:23 -0400 Received: by mail-pd0-f174.google.com with SMTP id y13so3728908pdi.5 for ; Sat, 22 Mar 2014 14:50:22 -0700 (PDT) Message-ID: <532E0598.6000902@ozlabs.ru> Date: Sun, 23 Mar 2014 08:50:16 +1100 From: Alexey Kardashevskiy MIME-Version: 1.0 References: <1394088217-4504-1-git-send-email-aik@ozlabs.ru> <87bnxjo2f3.fsf@pixel.localdomain> <53228F11.1020801@ozlabs.ru> <532DF031.40209@suse.de> <532DFAE8.90704@suse.de> In-Reply-To: <532DFAE8.90704@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH] usb-ohci: add vmstate descriptor List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= , Peter Maydell Cc: Mike Day , Gerd Hoffmann , QEMU Developers On 03/23/2014 08:04 AM, Andreas Färber wrote: > Am 22.03.2014 21:54, schrieb Peter Maydell: >> On 22 March 2014 20:18, Andreas Färber wrote: >>> Because AFAIU >>> migration is possible without VMSD, just not with VMSD that sets >>> .unmigratable = 1. >> >> Well, the migration won't fail with an error, but on the destination >> end you'll end up with a device in its reset state but a guest which >> may think the device is in some other state. If the device was >> quiescent and doesn't need complex setup it might cope, but >> more likely is that that guest driver will fall over in a heap next >> time you try to use it... > > Well, there is no OHCI state being added, only PCI state. So I'd be > curious to know what in there is the problem because a general review of > PCI devices might be due then - and ideally before we do the release. Without the patch, if to migrate a machine while it is in SLOF between BARs assigned and USB driver started working, the BAR memory regions were not enabled and BAR accesses were ending up in unassigned_mem_ops. -- Alexey