Re: [libvirt] [PATCH v2 7/8] Move the detach of PCI device to the beginnging of live hotplug

On 05/18/2016 05:35 PM, Shivaprasad G Bhat wrote: > The hostdevices are the only devices which have dependencies > outside of themselves such that, other functions of the PCI > card should also have been detached from host driver before > attempting the hotplug. > Are you saying that all the functions on a host device must be detached from their host driver, even if you're only assigning one or another of them to the guest? Yes. All devices from same iommu group should be detached from the host.

> This patch moves the detach to the beginning of the hotplug > so that the following patch can detach all funtions first before > attempting to hotplug any. > > We need not move the detach for net devices using SRIOV as > all SRIOV devices are single function devices. > I'm not sure why that makes any difference. In any case, you should detach all the devices that are going to be assigned, then assign them all, with the one going to function 0 being last.

> Signed-off-by: Shivaprasad G Bhat <sbhat(a)linux.vnet.ibm.com&gt; > --- > src/qemu/qemu_driver.c | 13 ++++++++++++- > src/qemu/qemu_hotplug.c | 18 +++++++++--------- > 2 files changed, 21 insertions(+), 10 deletions(-) > > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c > index 37d970e..9cff397 100644 > --- a/src/qemu/qemu_driver.c > +++ b/src/qemu/qemu_driver.c > @@ -8273,8 +8273,13 @@ static int > qemuDomainAttachDeviceFlags(virDomainPtr dom, const char *xml, > > VIR_DOMAIN_DEVICE_ACTION_ATTACH) < 0) > goto endjob; > - if ((ret = qemuDomainAttachDeviceLive(vm, dev_copy, dom)) < 0) > + if (dev_copy->type == VIR_DOMAIN_DEVICE_HOSTDEV && > + dev_copy->data.hostdev->source.subsys.type == > VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI && > + qemuDomainAttachPCIHostDevicePrepare(driver,vm->def, > dev_copy->data.hostdev, qemuCaps) < 0) > goto endjob; > + > + if ((ret = qemuDomainAttachDeviceLive(vm, dev_copy, dom)) < 0) > + goto undoprepare; > /* > * update domain status forcibly because the domain status may > be > * changed even if we failed to attach the device. For example, > @@ -8309,6 +8314,12 @@ static int > qemuDomainAttachDeviceFlags(virDomainPtr dom, const char *xml, > virObjectUnref(cfg); > virNWFilterUnlockFilterUpdates(); > return ret; > + > + undoprepare: > + if (dev_copy->type == VIR_DOMAIN_DEVICE_HOSTDEV && > + dev_copy->data.hostdev->source.subsys.type == > VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI) > + qemuHostdevReAttachPCIDevices(driver, vm->def->name, > &dev_copy->data.hostdev, 1); > + goto endjob; > } > static int qemuDomainAttachDevice(virDomainPtr dom, const char *xml) > diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c > index a2bcd89..bdfbafe 100644 > --- a/src/qemu/qemu_hotplug.c > +++ b/src/qemu/qemu_hotplug.c > @@ -899,6 +899,7 @@ qemuDomainAttachNetDevice(virQEMUDriverPtr driver, > actualType = virDomainNetGetActualType(net); > if (actualType == VIR_DOMAIN_NET_TYPE_HOSTDEV) { > + virDomainHostdevDefPtr hostdev = > virDomainNetGetActualHostdev(net); > /* This is really a "smart hostdev", so it should be attached > * as a hostdev (the hostdev code will reach over into the > * netdev-specific code as appropriate), then also added to > @@ -907,8 +908,14 @@ qemuDomainAttachNetDevice(virQEMUDriverPtr driver, > * qemuDomainAttachHostDevice uses a connection to resolve > * a SCSI hostdev secret, which is not this case, so pass NULL. > */ > - ret = qemuDomainAttachHostDevice(NULL, driver, vm, > - > virDomainNetGetActualHostdev(net)); > + if (qemuDomainAttachPCIHostDevicePrepare(driver, vm->def, > + hostdev, > priv->qemuCaps) < 0) > + goto cleanup; > + > + ret = qemuDomainAttachHostDevice(NULL, driver, vm, hostdev); > + if (!ret) > + qemuHostdevReAttachPCIDevices(driver, vm->def->name, > &hostdev, 1); > + > goto cleanup; > } > @@ -1248,10 +1255,6 @@ qemuDomainAttachHostPCIDevice(virQEMUDriverPtr > driver, > if (VIR_REALLOC_N(vm->def->hostdevs, vm->def->nhostdevs + 1) < 0) > return -1; > - if (qemuDomainAttachPCIHostDevicePrepare(driver, vm->def, > - hostdev, priv->qemuCaps) < > 0) > - return -1; > - > backend = hostdev->source.subsys.u.pci.backend; > /* Temporarily add the hostdev to the domain definition. This is > needed > @@ -1330,13 +1333,10 @@ qemuDomainAttachHostPCIDevice(virQEMUDriverPtr > driver, > if (releaseaddr) > qemuDomainReleaseDeviceAddress(vm, hostdev->info, NULL); > - qemuHostdevReAttachPCIDevices(driver, vm->def->name, &hostdev, 1); > - > VIR_FREE(devstr); > VIR_FREE(configfd_name); > VIR_FORCE_CLOSE(configfd); > - cleanup: > return -1; > } > > -- > libvir-list mailing list > libvir-list(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvir-list > >