Stephen Hemminger wrote: > On Wed, 30 Aug 2006 15:33:23 -0400 > John Kamenik <jkamenik@xxxxxxxxxx> wrote: > >> I have a question about applying VLANs to downed interfaces. I know >> that the kernel will not let you do it, and was wondering why? I >> have created a patch that removes this limitation and applied it to >> my system and everything works as I would expect it to. Was this a >> fix to a bug I am not currently seeing? >> >> I am using the 2.6.17 kernel and the attached patch is based on it. >> The only file changed was the net/8021q/vlan.c file. The >> "register_vlan_device" no longer makes a test to determine if the >> real (parent) interface is up. >> >> >> John T. Kamenik (Software Eng.) >> jkamenik@xxxxxxxxxx >> (301) 975 - 1000 (ext. 168) >> Patton Electronics Co. >> 7622 Rickenbacker Dr. >> Gaithersburg, Md 20879 >> > > I would be concerned about devices that do vlan acceleration. > The act of adding a vlan causes the device to have to talk to > the hardware. Often, the data structures for the hardware are > not allocated until after the device is brought up. > > So if you did this on drivers like sky2, e1000, forcedeth, r8169, > s2io, ... your change would crash. Would this be any different from bouncing an e100 ethX interface when VLANs were configured on it? I can't see why we shouldn't be able to relax that restriction and allow vlans on downed interfaces.... Ben -- Ben Greear <greearb@xxxxxxxxxxxxxxx> Candela Technologies Inc http://www.candelatech.com
