[openib-general] possible oops when callingipoib_neigh_destructor while ipoib mod ule is down.

[Fab Tillier]

> From: Roland Dreier [mailto:roland at topspin.com]
> Sent: Monday, November 29, 2004 9:33 AM
> 
> It does seem like IPoIB needs to keep track of all the neighbour
> structures it has added path context to.  When unregistering an
> interface, IPoIB should free the path context and reset the
> destructure.  However I'm not sure exactly how to do this while making
> sure the kernel hasn't freed the neighbour first (it seems there are
> some tricky races here).
> 

Maybe I'm clueless (quite likely), but why not just have each neighbour
structure take a reference on the module when it is created?  The destructor
would release that reference.  That should solve races involved with
cleaning up, as well as ensuring that the module is still around for the
destructor to get invoked.

- Fab