Hi.

On 12.11.2018 03:01, Steven Rostedt wrote:

On Sun, 11 Nov 2018 21:16:00 +0100
Oleksandr Natalenko [off-list ref] wrote:

quoted

Oh, I see that write_msg() calls netpoll_send_udp() under
spin_lock_irqsave(), but in PREEMPT_RT this, AFAIK, does not disable
interrupts.

So, the real question here is whether the interrupts should be indeed
disabled. And if so, -rt should replace spin_lock_irqsave() call there
with what? local_irq_save()? and get rid of the warning?

Why do we care if interrupts are disabled with PREEMPT_RT here?

I don't know, if you ask me. But the check was added intentionally with 
c9fd56b34efd0, so the author had definitely something on his mind. 
Cc'ing him.

printk() itself has a lot of issues with PREEMPT_RT that we are working
on dealing with. Right now netconsole is actually at the end of that
todo list.

OK, I see.

-- 
   Oleksandr Natalenko (post-factum)