Re: [libvirt] [PATCH] network: Defer online of macvtap during qemu migration

On 05/05/2014 12:26 PM, Matthew Rosato wrote: > When generating macvtaps via virNetDevMacVLanCreateWithVPortProfile, > the macvtap device is unconditionally set to the up state. However, > during migration, this results in a case where both the source and > target system are simultaneously up with the same MAC address. This > patch defers bringing the target macvtap up until later in the > migration to shrink this window. > > Signed-off-by: Matthew Rosato <mjrosato(a)linux.vnet.ibm.com&gt; Forgot to mention that this patch is associated with what Wangrui reported here: http://www.redhat.com/archives/libvir-list/2014-March/msg01054.html and follows Viktor's suggested solution mentioned here: http://www.redhat.com/archives/libvir-list/2014-March/msg01654.html

> --- > src/qemu/qemu_migration.c | 18 ++++++++++++++++++ > src/util/virnetdevmacvlan.c | 11 ++++++++--- > 2 files changed, 26 insertions(+), 3 deletions(-) > > diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c > index a9f7fea..aee803a 100644 > --- a/src/qemu/qemu_migration.c > +++ b/src/qemu/qemu_migration.c > @@ -56,6 +56,7 @@ > #include "virhook.h" > #include "virstring.h" > #include "virtypedparam.h" > +#include "virnetdev.h" > > #define VIR_FROM_THIS VIR_FROM_QEMU > > @@ -4468,6 +4469,8 @@ qemuMigrationFinish(virQEMUDriverPtr driver, > virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); > virCapsPtr caps = NULL; > unsigned short port; > + virDomainNetDefPtr net; > + size_t i; > > VIR_DEBUG("driver=%p, dconn=%p, vm=%p, cookiein=%s, cookieinlen=%d, " > "cookieout=%p, cookieoutlen=%p, flags=%lx, retcode=%d", > @@ -4574,6 +4577,21 @@ qemuMigrationFinish(virQEMUDriverPtr driver, > } > > if (!(flags & VIR_MIGRATE_PAUSED) && !(flags & VIR_MIGRATE_OFFLINE)) { > + /* Macvtaps were previously left offline, bring them online now */ > + for (i = 0; i < vm->def->nnets; i++) { > + net = vm->def->nets[i]; > + if (virDomainNetGetActualType(net) == VIR_DOMAIN_NET_TYPE_DIRECT) { > + if (virNetDevSetOnline(net->ifname, true) < 0) { > + ignore_value(virNetDevVPortProfileDisassociate(net->ifname, > + virDomainNetGetActualVirtPortProfile(net), > + &net->mac, > + virDomainNetGetActualDirectDev(net), > + -1, > + VIR_NETDEV_VPORT_PROFILE_OP_MIGRATE_IN_FINISH)); > + ignore_value(virNetDevMacVLanDelete(net->ifname)); > + } > + } > + } > /* run 'cont' on the destination, which allows migration on qemu > * >= 0.10.6 to work properly. This isn't strictly necessary on > * older qemu's, but it also doesn't hurt anything there > diff --git a/src/util/virnetdevmacvlan.c b/src/util/virnetdevmacvlan.c > index 7bbf540..3da845b 100644 > --- a/src/util/virnetdevmacvlan.c > +++ b/src/util/virnetdevmacvlan.c > @@ -898,9 +898,14 @@ int virNetDevMacVLanCreateWithVPortProfile(const char *tgifname, > goto link_del_exit; > } > > - if (virNetDevSetOnline(cr_ifname, true) < 0) { > - rc = -1; > - goto disassociate_exit; > + /* If this device is being created as part of an inbound > + * migration, leave the device offline for now. > + */ > + if (vmOp != VIR_NETDEV_VPORT_PROFILE_OP_MIGRATE_IN_START) { > + if (virNetDevSetOnline(cr_ifname, true) < 0) { > + rc = -1; > + goto disassociate_exit; > + } > } > > if (withTap) { > -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/mailman/listinfo/libvir-list