Commit bebd87ae authored by John Ogness's avatar John Ogness Committed by Petr Mladek
Browse files

printk: Track nbcon consoles 



Add a global flag @have_nbcon_console to identify if any nbcon
consoles are registered. This will be used in follow-up commits
to preserve legacy behavior when no nbcon consoles are registered.

Signed-off-by: default avatarJohn Ogness <john.ogness@linutronix.de>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-29-john.ogness@linutronix.de


Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
parent 60013065

kernel/printk/printk.c

+13 −1
Original line number Diff line number Diff line
@@ -470,6 +470,11 @@ static DEFINE_MUTEX(syslog_lock); 
 */

static bool have_legacy_console;



/*

 * Specifies if an nbcon console is registered.

 */

static bool have_nbcon_console;



/*

 * Specifies if a boot console is registered. If boot consoles are present,

 * nbcon consoles cannot print simultaneously and must be synchronized by
@@ -3638,6 +3643,7 @@ void register_console(struct console *newcon) 
	init_seq = get_init_console_seq(newcon, bootcon_registered);



	if (newcon->flags & CON_NBCON) {

		have_nbcon_console = true;

		nbcon_seq_force(newcon, init_seq);

	} else {

		have_legacy_console = true;
@@ -3718,6 +3724,7 @@ static int unregister_console_locked(struct console *console) 
{

	bool use_device_lock = (console->flags & CON_NBCON) && console->write_atomic;

	bool found_legacy_con = false;

	bool found_nbcon_con = false;

	bool found_boot_con = false;

	unsigned long flags;

	struct console *c;
@@ -3785,13 +3792,18 @@ static int unregister_console_locked(struct console *console) 
	for_each_console(c) {

		if (c->flags & CON_BOOT)

			found_boot_con = true;

		if (!(c->flags & CON_NBCON))



		if (c->flags & CON_NBCON)

			found_nbcon_con = true;

		else

			found_legacy_con = true;

	}

	if (!found_boot_con)

		have_boot_console = found_boot_con;

	if (!found_legacy_con)

		have_legacy_console = found_legacy_con;

	if (!found_nbcon_con)

		have_nbcon_console = found_nbcon_con;



	return res;

}