From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51765) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vikmn-0000OC-W3 for qemu-devel@nongnu.org; Tue, 19 Nov 2013 07:52:15 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Vikmi-0001Y9-Hu for qemu-devel@nongnu.org; Tue, 19 Nov 2013 07:52:09 -0500 Message-ID: <528B5EEE.5000705@suse.de> Date: Tue, 19 Nov 2013 13:51:58 +0100 From: =?ISO-8859-15?Q?Andreas_F=E4rber?= MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH for-1.7] pci: unregister vmstate_pcibus on unplug List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bandan Das , qemu-devel@nongnu.org, Michael Tsirkin Cc: Paolo Bonzini , qemu-stable , Anthony Liguori Am 06.11.2013 23:52, schrieb Bandan Das: >=20 > PCIBus registers a vmstate during init. Unregister it upon > removal/unplug. >=20 > Signed-off-by: Bandan Das Michael, this patch looks good for 1.7 to me, are you planning to still pick it up? Only one small comment below. Cc: qemu-stable@nongnu.org > --- > Note that I didn't add a instance_init to register vmstate (yet)=20 > due to concerns expressed by Andreas that we shouldn't be registering=20 > global state there. What's happening here is the following: instance_init does in fact not register anything, but vmstate_unregister() becomes a no-op loop if the vmsd+opaque combo is not registered, so it is safe. The registration happens in pci_bus_new() / pci_bus_new_inplace(), which I believe all PCI buses to date inside QEMU use, i.e. after instance_init, so in practice unregistering will not be no-op. > hw/pci/pci.c | 8 ++++++++ > 1 file changed, 8 insertions(+) >=20 > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > index a98c8a0..63ef7ce 100644 > --- a/hw/pci/pci.c > +++ b/hw/pci/pci.c > @@ -47,6 +47,7 @@ static void pcibus_dev_print(Monitor *mon, DeviceStat= e *dev, int indent); > static char *pcibus_get_dev_path(DeviceState *dev); > static char *pcibus_get_fw_dev_path(DeviceState *dev); > static int pcibus_reset(BusState *qbus); > +static void pci_bus_finalize(Object *obj); It may be nicer to avoid the prototype by moving the new pci_bus_finalize() above pci_bus_info. But since what counts is the fix to avoid segfaults during migration on access to a dangling opaque pointer after hot-unplug of a PCI-PCI bridge, Reviewed-by: Andreas F=E4rber Thanks, Andreas > =20 > static Property pci_props[] =3D { > DEFINE_PROP_PCI_DEVFN("addr", PCIDevice, devfn, -1), > @@ -73,6 +74,7 @@ static const TypeInfo pci_bus_info =3D { > .name =3D TYPE_PCI_BUS, > .parent =3D TYPE_BUS, > .instance_size =3D sizeof(PCIBus), > + .instance_finalize =3D pci_bus_finalize, > .class_init =3D pci_bus_class_init, > }; > =20 > @@ -401,6 +403,12 @@ int pci_bus_num(PCIBus *s) > return s->parent_dev->config[PCI_SECONDARY_BUS]; > } > =20 > +static void pci_bus_finalize(Object *obj) > +{ > + PCIBus *bus =3D PCI_BUS(obj); > + vmstate_unregister(NULL, &vmstate_pcibus, bus); > +} > + > static int get_pci_config_device(QEMUFile *f, void *pv, size_t size) > { > PCIDevice *s =3D container_of(pv, PCIDevice, config); --=20 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg, Germany GF: Jeff Hawn, Jennifer Guild, Felix Imend=F6rffer; HRB 16746 AG N=FCrnbe= rg