[libfabric-users] connection-less send/recv with verbs

[Hefty, Sean]

> I forgot to mention the version of libfabric I was using: git master,
> commit 8d192f2.

This is relatively recent, so you are probably fine.

> The backtrace is as follows (buf points to a 32-byte memory chunk):
> 
> #0  0x00007ffff798dd7e in fi_ibv_rdm_init_recv_request ()
>    from /archive/home/mdrocco/usr/lib/libfabric.so.1

My guess is that the crash is coming from this line:

request->context->internal[0] = (void *)request;

> #1  0x00007ffff798c728 in fi_ibv_rdm_recvmsg ()
>    from /archive/home/mdrocco/usr/lib/libfabric.so.1
> #2  0x00007ffff798c8bf in fi_ibv_rdm_recv ()
>    from /archive/home/mdrocco/usr/lib/libfabric.so.1
> #3  0x0000000000402937 in fi_recv (ep=0x6303d0, buf=0x633810, len=32,
>     desc=0x0, src_addr=18446744073709551615, context=0x0)

Since context is null.

The verbs RDM code requires the use of FI_CONTEXT.  So all context parameters must point to a struct fi_context.  The provider should have indicated this through the fi_info->mode bits, and the app should have set it.  I don't know if this is actually the case.