Re: spinlock recursion when running q800 emulation in qemu

Finn Thain
2024-03-08T09:14:10Z

On Fri, 8 Mar 2024, Michael Schmitz wrote:

>
> > IMHO, Gueunter would do better to instrument the spinlock tests on the
> > assumption that the locking in arch/m68k really is correct.
>
> I've come to agree - maybe logging any run queue locks taken by the init
> task with IRQs enabled might help?
>

If I understood how the spinlock test algorithm worked, I'd be adding
sanity checks to it to test the assumptions underlying that algorithm.

I would not be surprised if it uses logic that sees irqs_disabled() and
then assumes that all hard irqs are disabled, or something similar.

I don't think I'd be adding printk() because the BUG is intermittent and
printk() messes with timing.