Subject: Re: [PATCH] bridge: master device stuck in no-carrier state forever when in user-stp mode

From: Stephen Hemminger <[email-masked]>
Date: Tue, 29 Nov 2011 16:06:56 -0800

On Tue, 29 Nov 2011 18:54:33 -0500 (EST)
David Miller <[email-masked]> wrote:

> From: Vitalii Demianets <[email-masked]>
> Date: Fri, 25 Nov 2011 12:16:37 +0200
> 
> > When in user-stp mode, bridge master do not follow state of its slaves, so 
> > after the following sequence of events it can stuck forever in no-carrier 
> > state:
> > 1) turn stp off
> > 2) put all slaves down - master device will follow their state and also go in 
> > no-carrier state
> > 3) turn stp on with bridge-stp script returning 0 (go to the user-stp mode)
> > Now bridge master won't follow slaves' state and will never reach running 
> > state.
> > 
> > This patch solves the problem by making user-stp and kernel-stp behavior 
> > similar regarding master following slaves' states.
> > 
> > Signed-off-by: Vitalii Demianets <[email-masked]>
> 
> Stephen, please review this patch, thanks.

Agree that it is a problem, but want to fix the code up. The logic
can be done slightly cleaner.