[openib-general] Re: [PATCH] ipoib_flush_paths

[Sean Hefty]

Michael S. Tsirkin wrote:
> By the way, I was thinking about SA queries, and I came to a conclusion
> that we have an unfixable race at module unload: nothing I as the user of
> SA do in my callback can ensure that my callback is not still running
> when my module is unloaded.
> 
> The problem here is lack of explicit registration wth SA: I just push queries
> so there's no time SA can flush its queues for me.
> 
> The only easy way out that I see is some kind of sa_flush function that
> will flush MAD wqs, and ask all users to call that.
> And I think we have the same bug in addr so this needs a flush function too.
> 
> Makes sense?

Both ib_sa and ib_addr will always perform exactly one callback per request.  A 
user only needs to wait for that callback to occur.  The rdma_cm does this for 
ib_addr, and ib_multicast will do this for ib_sa.

- Sean