[LU-16949] LNet: deadlock on o2ib NI going down under Centos 7.9

Duplicate — Mon, 22 Jan 2024 17:20:19 +0000

The issue can be reproduced by adding an o2ib NI and then interrupting the corresponding link by pulling the cable or shutting down the switch connection or the whole switch.

Alternatively, one can add the o2ib NI when the corresponding link is already down (cable pulled) to the same effect.

Using "ifdown" to bring the whole interface down doesn't reproduce the problem.

I could reproduce this on a Centos 7.9 VM, but not on a Centos 8.2 system.

The issue got introduced by

commit da230373bd14306cb97fb48748ebce205f09d468
Author: Serguei Smirnov <ssmirnov@whamcloud.com>
Date:   Thu Feb 16 10:34:03 2023 -0800
LU-16563 lnet: use discovered ni status to set initial health

It then got masked by another issue causing failure when trying to add an o2ib NI starting from

commit cc5594df3e70d1924f34ccdf4c3178654d277ad0
Author: Shaun Tancheff <shaun.tancheff@hpe.com>
Date:   Sun Apr 23 07:19:11 2023 -0500
LU-16759 o2ib: MOFED 5.5+ ib_dma_virt_map_sg

until some later commit which I didn't determine re-enabled adding o2iblnd NI. The latest master is behaving on 7.9 Centos as described.

Whamcloud Community JIRA

[LU-16949] LNet: deadlock on o2ib NI going down under Centos 7.9