Well, it is. vlan=x really means "the ethernet segment named x". If
you connect all your guest nics to one vlan, you are
connecting them all
to one ethernet segment, so any packet transmitted on one will be
reflected on others.
Whether this is a useful feature is another matter, but the code is
functioning as expected.
Hello,
We had one environment where the NIC understood by u-boot and the NIC
understood by the kernel where different. We just attached both to the
same VLAN. During u-boot one was used for downloading the kernel, then
once the kernel booted the other was used. Not ideal, and maybe not
important enough to keep the "feature" around, but it does get used now
and again.