Re: [PATCH printk v6 00/30] wire up write_atomic() printing
From: Petr Mladek
Date: Tue May 28 2024 - 06:10:34 EST
On Mon 2024-05-27 08:43:19, John Ogness wrote:
> Hi,
>
> This is v6 of a series to wire up the nbcon consoles so that
> they actually perform printing using their write_atomic()
> callback. v5 is here [0]. For information about the motivation
> of the atomic consoles, please read the cover letter of v1 [1].
>
> The main focus of this series:
>
> - For nbcon consoles, always call write_atomic() directly from
> printk() caller context for the panic CPU.
>
> - For nbcon consoles, call write_atomic() when unlocking the
> console lock.
>
> - Only perform the console lock/unlock dance if legacy or boot
> consoles are registered.
>
> - For legacy consoles, if nbcon consoles are registered, do not
> attempt to print from printk() caller context for the panic
> CPU until nbcon consoles have had a chance to print the most
> significant messages.
>
> - Mark emergency sections. In these sections printk() calls
> will only store the messages. Upon exiting the emergency
> section, nbcon consoles are flushed directly. If legacy
> consoles cannot be flushed safely, an irq_work is triggered
> to do the legacy console flushing.
>
> This series does _not_ include threaded printing or nbcon
> drivers. Those features will be added in separate follow-up
> series.
>
> Note: With this series, a system with _only_ nbcon consoles
> registered will not perform console printing unless the
> console lock or nbcon port lock are used or on panic.
> This is on purpose. When nbcon kthreads are introduced,
> they will fill the gaps.
The series seems to be ready for linux-next from my POV.
I am going to push it there so that we get as much testing
as possible before the next merge window.
Best Regards,
Petr