Re: [LKP] 5404a7f1c2 [ 90.902541] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper:1]

From: Matthew Wilcox
Date: Tue Dec 18 2018 - 07:17:14 EST


On Tue, Dec 18, 2018 at 08:20:28AM +0800, kernel test robot wrote:
> Greetings,
>
> 0day kernel testing robot got the below dmesg and the first bad commit is
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
>
> commit 5404a7f1c21cfda061712bedf2d06cc0f6c755e9

I feel like you're wasting my time. This is the fourth time in a row
you've reported something I can't reproduce. At least this time the
instructions work, but I've tried it a dozen times and it doesn't produce
the error you're showing.

$ git branch
* (HEAD detached at 5404a7f1c21c)
...
[ 0.000000] Linux version 4.20.0-rc1-00012-g5404a7f1c21c (willy@bobo) (gcc version 8.2.0 (Debian 8.2.0-9)) #4 Mon Dec 17 23:28:21 EST 2018
...
[ 9.848471] test_uuid: all 18 tests passed
[ 11.019267] XArray: 19496249 of 19496249 tests passed

Your logs show it failing every time. I can't help but wonder if it's
something else in your setup that's causing it to fail -- maybe the
machines doing the testing are overloaded?