[PATCH] tty: keyboard.c: Remove locking from vt_get_leds.

[PATCH] tty: keyboard.c: Remove locking from vt_get_leds.

[Christopher Brannon]

There are three call sites for this function, and all three
are called within a keyboard handler.
kbd_event_lock is already held within keyboard handlers,
so attempting to lock it in vt_get_leds causes deadlock.

Signed-off-by: Christopher Brannon <chris@the-brannons.com>
---
 drivers/tty/vt/keyboard.c |    3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index 48cc6f2..770a854 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -1049,13 +1049,10 @@ static int kbd_update_leds_helper(struct input_handle *handle, void *data)
  */
 int vt_get_leds(int console, int flag)
 {
-	unsigned long flags;
 	struct kbd_struct * kbd = kbd_table + console;
 	int ret;
 
-	spin_lock_irqsave(&kbd_event_lock, flags);
 	ret = vc_kbd_led(kbd, flag);
-	spin_unlock_irqrestore(&kbd_event_lock, flags);
 
 	return ret;
 }
-- 
1.7.10.4

Re: [PATCH] tty: keyboard.c: Remove locking from vt_get_leds.

[Alan Cox]

On Fri, 22 Jun 2012 08:16:34 -0500
Christopher Brannon <chris@the-brannons.com> wrote:

> There are three call sites for this function, and all three
> are called within a keyboard handler.
> kbd_event_lock is already held within keyboard handlers,
> so attempting to lock it in vt_get_leds causes deadlock.
> 
> Signed-off-by: Christopher Brannon <chris@the-brannons.com>

Acked-by: Alan Cox <alan@linux.intel.com>