From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:54555) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SUOwo-00026x-EZ for qemu-devel@nongnu.org; Tue, 15 May 2012 17:06:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SUOwm-0002jH-NC for qemu-devel@nongnu.org; Tue, 15 May 2012 17:06:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46491) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SUOwm-0002j7-EI for qemu-devel@nongnu.org; Tue, 15 May 2012 17:06:20 -0400 Date: Wed, 16 May 2012 00:06:12 +0300 From: "Michael S. Tsirkin" Message-ID: <20120515210612.GC12039@redhat.com> References: <1337095599-28836-1-git-send-email-anthony.perard@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1337095599-28836-1-git-send-email-anthony.perard@citrix.com> Subject: Re: [Qemu-devel] [PATCH 1.1 0/4] Xen: Fix PV-on-HVM List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony PERARD Cc: Stefano Stabellini , QEMU-devel , Anthony Liguori , Xen Devel On Tue, May 15, 2012 at 04:26:35PM +0100, Anthony PERARD wrote: > In the context of PV-on-HVM under Xen, the emulated nics are supposed to be > unplug before the guest drivers are initialized. Guest drivers for which device? > This mean that there must be unplug without the consent of the guest. > Without this patch series, the guest end up with two nics with the > same MAC, the emulated nic and the PV nic. Shouldn't be a problem if one of them has link down state. So maybe just be careful not to bring PV link up until after emulated nic goes away? > I tried few other path before to submite these patches: > - delayed the hot unplug in QEMU until the guest initialize the hotplug. > => the guest unplug the nic only after the driver initialized it. That's a > bit late. > - delayed the call to unplug the emulated device until pci_acpi_init is called > => this is worse, the pv disc does not show up and the guest does not boot. > > In order to achive this fix, these patches introduce a new hotplug state only > used in acpi_piix4, and a new qdev callback force_unplug. > > Would it be possible to have this fix in the next release? > > Thanks, > > > Anthony PERARD (4): > Introduce a new hotplug state: Force eject. > qdev: Introduce qdev_force_unplug. > pci: Add force_unplug callback. > xen: Fix PV-on-HVM > > hw/acpi_piix4.c | 5 +++++ > hw/pci.c | 15 +++++++++++++-- > hw/pci.h | 1 + > hw/qdev.c | 23 ++++++++++++++++++++--- > hw/qdev.h | 3 +++ > hw/xen_platform.c | 2 +- > 6 files changed, 43 insertions(+), 6 deletions(-) > > -- > Anthony PERARD