report error "Failed setting ABI version ioctl - may be r21p0 or later..." about gator

[bengaineyarm]

Hi

This doesn't look like a gator issue, but a rt kernel issue:

[ 6019.630453@0] kernel BUG at kernel/sched/rt.c:932!

[heyg]

Hi Ben,
Thanks for your reply.

Actually, I have back to back to 6.5.1 version in upstream/master, it work normal.
checkout commit c405285

I used kernel4.9， I am not sure the kernel needs any other cl?

[bengaineyarm]

Are you saying that all previous version of gator, upto 6.5.1 also trigger this failure, but not 6.5.1 or earlier?

Are you using preempt_rt kernel, or just normal kernel?

[heyg]

Hi Ben,
I only try 6.5.1, and kernel4.9 is not enabled CONFIG_PREEMPT_RT.

[bengaineyarm]

Ok, got it.

From that trace, it looks like it is calling into the "CoreOnliner" class in gatord (which is used to try to force all the CPU's to turn on so that gator can identify them), at which point it is triggering a debug warning in the kernel.

[ 6019.617349@0] sched: RT throttling activated for rt_rq ffffffc061b2baa8 (cpu 0)
[ 6019.617349@0] potential CPU hogs:
[ 6019.617349@0] gatord-cid-0 (3930)
[ 6019.625692@0] ------------[ cut here ]------------
[ 6019.630453@0] kernel BUG at kernel/sched/rt.c:932!

A few things you can try:

• Do you have CONFIG_PANIC_ON_RT_THROTTLING set? You can try turning it off?
• If it is set? Does it cause gator to fail, or can you continue and just ignore the warning?
• If you have a more recent version of gatord, you can pass --disable-cpu-onlining yes option which should disable the CoreOnliner class

[heyg]

Hi Ben,
Yes, I enabled CONFIG_PANIC_ON_RT_THROTTLING.

In fact, I got useful information in 6.5.1, and my problem has been solved.
I am currently stuck in another project and I will follow your suggestions to retry once I have time.

Thank you for your careful analysis.

[bengaineyarm]

👍 no worries; let me know how you get on, thanks.