2.6.36-stable review patch. If anyone has any objections, please let us know.
------------------ From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <[email protected]> commit d1d73578e053b981c3611e5a211534290d24a5eb upstream. According to the comment describing ops_lock in the definition of struct backlight_device and when comparing with other functions in backlight.c the mutex must be hold when checking ops to be non-NULL. Fixes a problem added by c835ee7f4154992e6 ("backlight: Add suspend/resume support to the backlight core") in Jan 2009. Signed-off-by: Uwe Kleine-König <[email protected]> Acked-by: Richard Purdie <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/video/backlight/backlight.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -197,12 +197,12 @@ static int backlight_suspend(struct devi { struct backlight_device *bd = to_backlight_device(dev); - if (bd->ops->options & BL_CORE_SUSPENDRESUME) { - mutex_lock(&bd->ops_lock); + mutex_lock(&bd->ops_lock); + if (bd->ops && bd->ops->options & BL_CORE_SUSPENDRESUME) { bd->props.state |= BL_CORE_SUSPENDED; backlight_update_status(bd); - mutex_unlock(&bd->ops_lock); } + mutex_unlock(&bd->ops_lock); return 0; } @@ -211,12 +211,12 @@ static int backlight_resume(struct devic { struct backlight_device *bd = to_backlight_device(dev); - if (bd->ops->options & BL_CORE_SUSPENDRESUME) { - mutex_lock(&bd->ops_lock); + mutex_lock(&bd->ops_lock); + if (bd->ops && bd->ops->options & BL_CORE_SUSPENDRESUME) { bd->props.state &= ~BL_CORE_SUSPENDED; backlight_update_status(bd); - mutex_unlock(&bd->ops_lock); } + mutex_unlock(&bd->ops_lock); return 0; }
_______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
