Infiniband/RDMA rules absent

[Arne Redlich]

Binary package hint: udev

Ubuntu release: 10.10, amd64
udev version: 162-2

After upgrading from 10.04 to 10.10 the udev rules for Infiniband / RDMA device nodes have vanished, rendering all applications that rely on their presence (in short: the infiniband / RDMA stack) dysfunctional.

Manually adding the 40-infiniband.rules file from 10.04 works around the issue.

[Etienne Goyer (etienne-goyer-outlands)]

It seems to be missing from upstream too. Actually, it disappeared somewhere between udev-151 and udev-152.

[Roland Dreier (roland.dreier)]

The idea from udev upstream is that if device files are supposed to be, say, in /dev/infiniband then the kernel should know that instead of the udev rules. I merged the required kernel changes into kernel 3.0.0-rc1, so Oneiric should be better.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Alessandro Polverini (polve)]

Just checked on Oneiric and it seems that the rules are not there. This command gives an empty result:
grep -i infiniband `dpkg -L udev`

While doing it on debian squeeze I get this:

/lib/udev/rules.d/50-udev-default.rules:KERNEL=="umad*", NAME="infiniband/%k"
/lib/udev/rules.d/50-udev-default.rules:KERNEL=="issm*", NAME="infiniband/%k"
/lib/udev/rules.d/50-udev-default.rules:KERNEL=="uverbs*", NAME="infiniband/%k"
/lib/udev/rules.d/50-udev-default.rules:KERNEL=="ucm*", NAME="infiniband/%k"
/lib/udev/rules.d/50-udev-default.rules:KERNEL=="uat", NAME="infiniband/%k"
/lib/udev/rules.d/50-udev-default.rules:KERNEL=="ucma", NAME="infiniband/%k"
/lib/udev/rules.d/50-udev-default.rules:KERNEL=="rdma_cm", NAME="infiniband/%k"

[Roland Dreier (roland.dreier)]

FWIW, on my Oneiric system, I did "modprobe rdma_ucm" and I see:

$ ls -l /dev/infiniband/
total 0
crw-rw-rw- 1 root root 10, 57 2011-11-07 10:34 rdma_cm

so with kernel 3.0 or newer, things work as expected.

(You can try this with a system that doesn't have any RDMA hardware)

As far as I know, this bug is only an issue on Natty and older.