Red Hat Bugzilla – Bug 170053
Add udev rule for InfiniBand userspace access devices
Last modified: 2007-11-30 17:11:14 EST
The direct userspace access support included with the kernel's
InfiniBand drivers in kernels 2.6.13 and newer creates character
devices named uverbs0, uverbs1, etc. Please add a udev rule:
KERNEL="uverbs*", NAME="infiniband/%k", MODE="0660", GROUP="rdma"
to create the device nodes.
As you can see, I am suggesting that these nodes be owned by an "rdma"
group. This is analogous to other groups used for device nodes, such
as "dialout" or "cdrom" -- the uverbs devices are fairly safe to allow
ordinary users access to, but an administrator should be able to
control which users can use the device.
I suggest the name "rdma" for the group name because these device
nodes give userspace programs access to RDMA capabilities from
InfiniBand and (someday) iWARP hardware.
Of course, this requires the creation of the rdma group. I'm not sure
where or how this sort of group is managed, so please let me know if
there's any other avenues I should be sending this request to.
Which userspace apps?
Apps will generally use this through an MPI library such as Open MPI
(http://open-mpi.org) or MVAPICH
(http://nowlab.cse.ohio-state.edu/projects/mpi-iba/). These libraries access
InfiniBand through the libibverbs library, which I have packaged for Fedora
Extras (open request for review in bug 169743).