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ps://elixir.bootlin.com/linux/latest/source/kernel/printk/printk_safe.c#L382

> That depends on printk_nmi_direct_enter() to set the context, wouldn't
> an equivalent printk_ve_direct_enter() context flag be needed as well?

Even without it the console semaphore is always trylocked. So recursion 
is just not possible.

What would be possible is a endless loop (printk adding more information 
to the log buffer, which is then printed etc.), but that's true for 
everywhere in the console/serial driver subsystem.


-Andi