diff mbox series

[printk,v3,38/40] tty: serial: kgdboc: use console_list_lock to trap exit

Message ID 20221107141638.3790965-39-john.ogness@linutronix.de
State New
Headers
Series reduce console_lock scope |

Commit Message

John Ogness Nov. 7, 2022, 2:16 p.m. UTC 
  kgdboc_earlycon_init() uses the console_lock to ensure that no consoles
are unregistered until the kgdboc_earlycon is setup. The console_list_lock
should be used instead because list synchronization responsibility will
be removed from the console_lock in a later change.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
---
 drivers/tty/serial/kgdboc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Daniel Thompson Nov. 10, 2022, 3:18 p.m. UTC | #1 
On Mon, Nov 07, 2022 at 03:22:36PM +0106, John Ogness wrote:
> kgdboc_earlycon_init() uses the console_lock to ensure that no consoles
> are unregistered until the kgdboc_earlycon is setup. The console_list_lock
> should be used instead because list synchronization responsibility will
> be removed from the console_lock in a later change.
> 
> Signed-off-by: John Ogness <john.ogness@linutronix.de>

I've not looked at the other patches in the series to understand the
future tense here (e.g. why we need intermediate patches like this one).

However I've no objections to the change so:
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>


Daniel.


> ---
>  drivers/tty/serial/kgdboc.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
> index 8c2b7ccdfebf..a3ed9b34e2ab 100644
> --- a/drivers/tty/serial/kgdboc.c
> +++ b/drivers/tty/serial/kgdboc.c
> @@ -558,13 +558,13 @@ static int __init kgdboc_earlycon_init(char *opt)
>  	 */
>  
>  	/*
> -	 * Hold the console_lock to guarantee that no consoles are
> +	 * Hold the console_list_lock to guarantee that no consoles are
>  	 * unregistered until the kgdboc_earlycon setup is complete.
>  	 * Trapping the exit() callback relies on exit() not being
>  	 * called until the trap is setup. This also allows safe
>  	 * traversal of the console list and race-free reading of @flags.
>  	 */
> -	console_lock();
> +	console_list_lock();
>  	for_each_console(con) {
>  		if (con->write && con->read &&
>  		    (con->flags & (CON_BOOT | CON_ENABLED)) &&
> @@ -606,7 +606,7 @@ static int __init kgdboc_earlycon_init(char *opt)
>  	}
>  
>  unlock:
> -	console_unlock();
> +	console_list_unlock();
>  
>  	/* Non-zero means malformed option so we always return zero */
>  	return 0;
> -- 
> 2.30.2
>
Petr Mladek Nov. 11, 2022, 9:59 a.m. UTC | #2 
On Mon 2022-11-07 15:22:36, John Ogness wrote:
> kgdboc_earlycon_init() uses the console_lock to ensure that no consoles
> are unregistered until the kgdboc_earlycon is setup. The console_list_lock
> should be used instead because list synchronization responsibility will
> be removed from the console_lock in a later change.
> 
> Signed-off-by: John Ogness <john.ogness@linutronix.de>

Reviewed-by: Petr Mladek <pmladek@suse.com>

Best Regards,
Petr
diff mbox series

Patch

diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
index 8c2b7ccdfebf..a3ed9b34e2ab 100644
--- a/drivers/tty/serial/kgdboc.c
+++ b/drivers/tty/serial/kgdboc.c
@@ -558,13 +558,13 @@  static int __init kgdboc_earlycon_init(char *opt)
 	 */
 
 	/*
-	 * Hold the console_lock to guarantee that no consoles are
+	 * Hold the console_list_lock to guarantee that no consoles are
 	 * unregistered until the kgdboc_earlycon setup is complete.
 	 * Trapping the exit() callback relies on exit() not being
 	 * called until the trap is setup. This also allows safe
 	 * traversal of the console list and race-free reading of @flags.
 	 */
-	console_lock();
+	console_list_lock();
 	for_each_console(con) {
 		if (con->write && con->read &&
 		    (con->flags & (CON_BOOT | CON_ENABLED)) &&
@@ -606,7 +606,7 @@  static int __init kgdboc_earlycon_init(char *opt)
 	}
 
 unlock:
-	console_unlock();
+	console_list_unlock();
 
 	/* Non-zero means malformed option so we always return zero */
 	return 0;