Re: [libvirt] [PATCH] netdev: assure that SRIOV PF is online before modifying VF params

On 14.05.2015 21:38, Laine Stump wrote: > The kernel won't complain if you set the mac address and vlan tag for > an SRIOV VF via its PF, and it will even let you assign the PF to a > guest using PCI device assignment or macvtap passthrough. But if the > PF isn't online, the device won't be usable in the guest. This patch > makes sure that it is turned on. > > Since multiple guests/VFs could use the same PF, there is no point in > ever setting the PF *off*line. > > This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=893738 > > Originally filed against RHEL6, but present in every version of > libvirt until today. > --- > src/util/virnetdev.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/src/util/virnetdev.c b/src/util/virnetdev.c > index e14b401..7022dfa 100644 > --- a/src/util/virnetdev.c > +++ b/src/util/virnetdev.c > @@ -2258,6 +2258,17 @@ virNetDevReplaceVfConfig(const char *pflinkdev, int vf, > char macstr[VIR_MAC_STRING_BUFLEN]; > char *fileData = NULL; > int ifindex = -1; > + bool pfIsOnline; > + > + /* Assure that PF is online prior to twiddling with the VF. It > + * *should* be, but if the PF isn't online the changes made to the > + * VF via the PF won't take effect, yet there will be no error > + * reported. > + */ > + if (virNetDevGetOnline(pflinkdev, &pfIsOnline) < 0) > + return ret; > + if (!pfIsOnline && virNetDevSetOnline(pflinkdev, true) < 0) > + return ret; > > if (virNetDevGetVfConfig(pflinkdev, vf, &oldmac, &oldvlanid) < 0) > goto cleanup; > ACK. Should we set the device back to its previous state if something goes wrong later in the function?