[openib-general] on calling rdma_disconnect from non sleepablecontext

[Roland Dreier]

 > I have now instrumented iser code to always call rdma_disconnect /
 > rdma_destory_qp etc from sleepable context. Before doing so i was
 > getting this oops few times. My interpertation was that
 > cma_modify_qp_err is not supposted to get called when in_atomic is
 > true, am i correct?

Yes, the modify QP operation might sleep.  For example, on Mellanox
hardware, modifying a QP requires a firmware command, which allocates
a mailbox with GFP_KERNEL and also sleeps until the command completes.

I tried to document these sorts of rules in Documentation/infiniband/core_locking.txt

 - R.