Hi!

> > I notice you are using -rt kernel. Do you actually need realtime
> > features?
> 
> Yes, I actually need the realtime feature. I have one task which
> needs to run periodically in realtime (triggered every 10ms by an
> external IRQ).

How fast response do you need to the external IRQ?

> > Can you try to reproduce the problem on 4.19.193?
> 
> This is only a problem with the realtime patch. The patch
> introduces migrate_enable which is part of the callstack:
> 
> Jun 1 09:11:46 sicam kernel: [46802.944165] BUG: using smp_processor_id() in preemptible [00000000] code: TCPTSK/1809
> Jun 1 09:11:46 sicam kernel: [46802.944210] caller is
> migrate_enable+0x40/0x488

Fun :-(. As Jan mentioned, testing if it can be reproduced with
4.19.193-rt81 would be useful.

Best regards,
								Pavel

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