Re: [dpdk-dev] kernel: BUG: soft lockup - CPU#1 stuck for 22s! [kni_single:1782]

[Alejandro Lucero <alejandro.lucero@netronome.com>]

Hi Jay,

I saw these errors when I worked in the HPC sector. They come usually with
a kernel dump for each core in the machine so you can know, after some
peering at the kernel code, how the soft lockup triggers. When I did that
it was always an issue with the memory.

So those times that you can still work on the machine after the problem,
look at the kernel messages. I will be glad to look at it.



On Wed, Feb 11, 2015 at 1:33 AM, Jay Rolette <rolette@infiniteio.com> wrote:

> Environment:
>   * DPDK 1.6.0r2
>   * Ubuntu 14.04 LTS
>   * kernel: 3.13.0-38-generic
>
> When we start exercising KNI a fair bit (transferring files across it, both
> sending and receiving), I'm starting to see a fair bit of these kernel
> lockups:
>
> kernel: BUG: soft lockup - CPU#1 stuck for 22s! [kni_single:1782]
>
> Frequently I can't do much other than get a screenshot of the error message
> coming across the console session once we get into this state, so debugging
> what is happening is "interesting"...
>
> I've seen this on multiple hardware platforms (so not box specific) as well
> as virtual machines.
>
> Are there any known issues with KNI that would cause kernel lockups in DPDK
> 1.6? Really hoping someone that knows KNI well can point me in the right
> direction.
>
> KNI in the 1.8 tree is significantly different, so it didn't look
> straight-forward to back-port it, although I do see a few changes that
> might be relevant.
>
> Any suggestions, pointers or other general help for tracking this down?
>
> Thanks!
> Jay
>