Re: [PATCH printk v5 12/30] serial: core: Implement processing in port->lock wrapper

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, May 02, 2024 at 11:44:21PM +0206, John Ogness wrote:
> Currently the port->lock wrappers uart_port_lock(),
> uart_port_unlock() (and their variants) only lock/unlock
> the spin_lock.
> 
> If the port is an nbcon console, the wrappers must also
> acquire/release the console and mark the region as unsafe. This
> allows general port->lock synchronization to be synchronized
> with the nbcon console ownership.
> 
> Note that __uart_port_using_nbcon() relies on the port->lock
> being held while a console is added and removed from the
> console list (i.e. all uart nbcon drivers *must* take the
> port->lock in their device_lock() callbacks).
> 
> Signed-off-by: John Ogness <john.ogness@linutronix.de>
> ---
>  include/linux/serial_core.h | 82 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 80 insertions(+), 2 deletions(-)

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>