Re: [PATCH net] ibmveth: use net_err_ratelimited when set_multicast_list

[Hangbin Liu <liuhangbin@gmail.com>]

On Thu, Aug 01, 2019 at 12:51:14PM -0400, David Miller wrote:
> From: Hangbin Liu <liuhangbin@gmail.com>
> Date: Thu,  1 Aug 2019 17:03:47 +0800
> 
> > When setting lots of multicast list on ibmveth, e.g. add 3000 membership on a
> > multicast group, the following error message flushes our log file
> > 
> > 8507    [  901.478251] ibmveth 30000003 env3: h_multicast_ctrl rc=4 when adding an entry to the filter table
> > ...
> > 1718386 [ 5636.808658] ibmveth 30000003 env3: h_multicast_ctrl rc=4 when adding an entry to the filter table
> > 
> > We got 1.5 million lines of messages in 1.3h. Let's replace netdev_err() by
> > net_err_ratelimited() to avoid this issue. I don't use netdev_err_once() in
> > case h_multicast_ctrl() return different lpar_rc types.
> > 
> > Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
> 
> Let's work on fixing what causes this problem, or adding a retry
> mechanism, rather than making the message less painful.

Yes, the multicast issue should also be fixed. It looks more like a
driver issue as I haven't seen it on other drivers.

I think these should be two different fixes.

Thanks
Hangbin
> 
> What is worse is that these failures are not in any way communicated
> back up the callchain to show that the operation didn't complete
> sucessfully.
> 
> This is a real mess in behavior and error handling, don't make it
> worse please.