[ 14/58] tty: keyboard.c: Remove locking from vt_get_leds.

From: Greg Kroah-Hartman
Date: Thu Oct 04 2012 - 18:03:16 EST


3.5-stable review patch. If anyone has any objections, please let me know.

------------------

From: Christopher Brannon <chris@xxxxxxxxxxxxxxxx>

commit 157a4b311c45c9aba75a990464d9680867dc8805 upstream.

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@xxxxxxxxxxxxxxxx>
Acked-by: Alan Cox <alan@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/tty/vt/keyboard.c | 3 ---
1 file changed, 3 deletions(-)

--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -1049,13 +1049,10 @@ static int kbd_update_leds_helper(struct
*/
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;
}


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