[ofa-general] Re: How to tell what OFED rev a distro derived IB modules?

[Jack Morgenstein]

On Friday 24 April 2009 02:48, Jason Gunthorpe wrote:
> AFAIK, Ubuntu does not do any work on their IB drivers, so the driver
> is stock 2.6.27.
> 
> In principle OFED is supposed to start with an upstream kernel and
> backport those drivers to various distributions. OFED 1.3 was using
> 2.6.24, OFED 1.4 is apparently using 2.6.27.
> 
> So it should be similar to OFED 1.4
> 
> Though bear in mind OFED still patches things with stuff that is not
> yet accepted upstream so there will be some differences.
> 
> It should be compatible with the OFED 1.4 userspace.
> 
Beware -- you should not use OFED userspace with a non-ofed kernel for ConnectX HCAs.
The OFED 1.4 ConnectX driver includes the XRC (Extended RC) patches -- which grab
23 (the MSB) of the QP number to indicate an XRC SRQ in CQEs.  Non-OFED kernels do not
reserve bit 23 for this usage, so you will experience incompatibility problems.

In general, you should not use OFED userspace libraries with non-OFED kernel distributions.

- Jack