Hi, In 802.1Qbh case where exists a SR-IOV capable network device, if any of the virtual functions of this device is used in hostdev mode for the guest, port-profile disassociate will also cause physical function interface to go down. This appears to be a bug, but wanted to find if this was done intentionally for some reasons. To be more specific, if a network device supports SRIOV and its VF is being used in pci passthrough mode, when the guest is shutdown or destroyed following happens - qemuProcessStop \_ qemuDomainReAttachHostdevDevices(hostdevs) \_ qemuDomainHostdevNetConfigRestore(hostdev) \_ virNetDevPortProfileDisassociate(linkdev) \_ virNetDevSetOnline(linkdev, false) In above, qemuDomainHostdevNetConfigRestore() finds out the PF for provided hostdev (which is VF) and passes it to virNetDevPortProfileDisassociate() as linkdev. Later, linkdev gets passed to virNetDevSetOnline() where the interface is brought down by clearing IFF_UP flag. However, in macvtap emulation mode, virNetDevMacVLanDeleteWithVPortProfile() passes VF as linkdev (and -1 as vf) to virNetDevPortProfileDisassociate(), hence, not affecting PF at all. Bringing down a PF, when only VF is being brought down is not expected behavior (unless, I'm missing something here). A way to get around it would be to check if there exists vf (>=0) in virNetDevPortProfileDisassociate(), and if so, it should only pass the interface name of this VF rather than PF itself to virNetDevSetOnline(). If it sounds reasonable, I'll send out a fix.

-----Original Message----- From: Nishank Trivedi (nistrive) Sent: Wednesday, August 08, 2012 10:22 AM To: Laine Stump; libvir-list(a)redhat.com Cc: Christian Benvenuti (benve) Subject: Re: [libvirt] PF interface brought down if guest using a VF in hostdev mode under 802.1Qbh On 8/7/12 8:15 PM, "Laine Stump" <laine(a)laine.org&gt; wrote: > >Yes, I believe you are correct that virNetDevSetOnline is being called >with the wrong device name (I could be wrong though - is there maybe >some odd rule that the PF must be UP before the VFs will be up? PF should be UP prior to VF only if there is some proxy'ing or some control data being sent by PF on behalf of VF. Same could be true for bringing VF down. >In case >case, we certainly shouldn't be setting the PF to IFF_DOWN). But in the >case of PCI passthrough, does it even need to be called at all? Not for PF for sure. While VF is getting disassociated with port profile, VF interface still needs to be brought down. So virNetDevSetOnline should be passed VF interface, if vf >= 0.

> >Cc'ing Roopa in case she missed this in all the other traffic. Invalid email id, cc'ing Christian instead. Thanks, Nishank