Re: watchdog: BUG: soft lockup

[Petr Mladek <pmladek@suse.com>]

On Mon 2024-12-23 14:32:11, wzs wrote:
> Hello,
> when fuzzing the Linux kernel,
> I triggered many "watch: BUG: soft lockup" warnings.
> I am not sure whether this is an issue with the kernel or with the
> fuzzing program I ran.
> (The same fuzzing program, when tested on kernel versions from
> Linux-6.7.0 to 6.12.0, triggers the 'watchdog: BUG: soft lockup'
> warning on some versions, while others do not. Linux 6.12.0 is the
> latest stable release where this error occurs.)

I am not sure if I understand the above correctly.

Did you test also kernel versions older than 6.7.0 or newer then 6.12.0?

Was the result random? Like for example, did you saw the problem
on 6.7.0 and 6.12.0 but not on 6.9.0?

Did you try to run the test more times with the same version of the
kernel? Was it reproducible?

I guess that the problem is in all versions but it is not 100%
reproducible. So that the softlockup happens or does not happen by chance.


> The bug information I provided below is from the Linux-6.12.0 kernel.
> If you need bug information from other versions, I would be happy to provide it.
> 
> kernel config :https://pastebin.com/i4LPXNAN
> console output :https://pastebin.com/uKVpvJ78

It would be great to see at least three logs. It might help to find
a common pattern.

Also it would be great to provide a full log if possible. Or at least
the boot part and few more lines before the crash.

Best Regards,
Petr