Re: [PATCH v5 0/2] printk: Console owner and waiter logic cleanup

Tejun Heo
2018-01-16T19:45:02Z

Hello, Steven.

On Thu, Jan 11, 2018 at 09:55:47PM -0500, Steven Rostedt wrote:
> All I did was start off a work queue on each CPU, and each CPU does one
> printk() followed by a millisecond sleep. No 10,000 printks, nothing
> in an interrupt handler. Preemption is disabled while the printk
> happens, but that's normal.
>
> This is much closer to an OOM happening all over the system, where OOMs
> stack dumps are occurring on different CPUS.

OOMs can't happen all over the system. It can only happen on a single
CPU at a time. If you're printing from multiple CPUs, your solution
would work great. That is the situation your patches are designed to
address to begin with. That isn't the problem that I reported tho. I
understand that your solution works for that class of problems and
that is great. I really wish that it could address the other class of
problems too tho, and it doesn't seem like it would be that difficult
to cover both cases, right?

Thanks.

--
tejun