[ofa-general] Re: [ewg] [PATCH] IB/ipoib: avoid WARN_ON on NULL path->ah

[Moni Shoua]

Eli Cohen wrote:
> Commit ee1e2c82c245a5fb2864e9dbcdaab3390fde3fcc introduced an
> optimization on path flushing. This caused a new possible scenario in
> which unicast_arp_send triggers path query which could fail, causing
> path->ah to become NULL. A successive successfull path query will then
> trigger WARN_ON() in path_rec_completion(). This fix requires old_ah
> to differ from NULL as a prerequsite to trigger the WARN_ON().
> Moreover, that commit also allowed path resolution to be triggered for
> an invalid path; if that path resolution failed, old_ah would be freed
> outside priv->lock violating the assumption that dropping references
> inside the lock are guaranteed not to reach zero reference.
> 

Eli Roland,
I understand that this patch is going to be in OFED. 
What about upstream kernel?
I'd like to add improvements to commit ee1e2c82c245a5fb2864e9dbcdaab3390fde3fcc (the one you referred  to) and it will probably be on top of your fix.

I'm sorry if I missed Roland's answer.

thanks