Re: [PATCH net] bridge: fix hello and hold timers starting/stopping

On Fri, 19 May 2017 18:25:43 +0200
Ivan Vecera [off-list ref] wrote:

Current bridge code incorrectly handles starting/stopping of hello and
hold timers during STP enable/disable.

1. Timers are stopped in br_stp_start() during NO_STP->USER_STP
   transition. This is not correct as the timers are stopped in NO_STP
   case.

2. Timers are started in br_stp_stop() during USER_STP->NO_STP transition.
   This is not also correct as the timers should be stopped in NO_STP
   state.

3. Timers are NOT stopped in br_stp_stop() during KERNEL_STP->NO_STP
   transition. They should be stopped as they are running in KERNEL_STP
   state and should not run in NO_STP case.

The patch is a follow-up for "bridge: start hello_timer when enabling
KERNEL_STP in br_stp_start" patch from Xin Long.

Cc: davem@davemloft.net
Cc: sashok@cumulusnetworks.com
Cc: stephen@networkplumber.org
Cc: bridge@lists.linux-foundation.org
Cc: lucien.xin@gmail.com
Cc: nikolay@cumulusnetworks.com
Signed-off-by: Ivan Vecera <redacted>

Overall, this looks correct but the wording of commit message
is too terse.

It would be better to add a more complete description of the impact
of this from a user's point of view. I am concerned that this
might have other side effects.

For example, what is the sequence of commands to validated this.

What is the impact, should this go to stable?