[ewg] OFED-4.8, rdma-core, and library paths

[Steve Wise]

> 
> Hm, possibly yes. ibverbs first checks the new location, if the
> provider is not there then it will fall back to a naked dlopen which
> could find providers in the system library path if there was a .driver
> file for it.
> 

Hmm, so it will load the provider libraries directly specifying the full path?
IE 'ldconfig -p' doesn't matter?

> However, starting in rdma-core 13 the distro providers will not be
> link compatible with new libibverbs and will silently fail to load.
> 
> > What do folks think about this?  Should OFED-4.8 try and uninstall rdma
> > cmds/libs regardless of where they came from?  Perhaps optionally.  Or
should
> > this just be documented so the admin is required to deal with it?  I think
if we
> > leave OFED as-is, we'll end up with lots of support issues where old libs
are
> > being loaded causing problems.
> 
> I'm not sure it is likely someone will hit this. The user would need a
> distro packaged provider that is not included in rdma-core. AFAIK no
> such thing exists...
>

Vlad already clarified that the OFED installer uninstalls distro rpms, so I
think OFED is good.

> 
> Do you know of another way to trigger wrong loading?
> 

Actually, I was assuming the load path used by libibverbs would be done based on
'ldconfig -p'.  If that is not the case, then everything is ok...I think. 

Steve.