Hi, On Mon, Nov 11, 2013 at 03:37:37PM +0200, Tomi Valkeinen wrote: > On 2013-11-06 23:24, Aaro Koskinen wrote: > > When booting Nokia N900 smartphone with v3.12 + omap2plus_defconfig > > (LOCKDEP enabled) and CONFIG_DISPLAY_PANEL_SONY_ACX565AKM enabled, > > the following BUG is seen during the boot: > > > > [ 7.302154] ===================================== > > [ 7.307128] [ BUG: bad unlock balance detected! ] > > [ 7.312103] 3.12.0-los.git-2093492-00120-g5e01dc7 #3 Not tainted > > [ 7.318450] ------------------------------------- > > [ 7.323425] kworker/u2:1/12 is trying to release lock (&ddata->mutex) at: > > [ 7.330657] [<c031b760>] acx565akm_enable+0x12c/0x18c > > [ 7.335998] but there are no more locks to release! > > > > Fix by removing the extra mutex_unlock(). > > > > Reported-by: Eduardo Valentin <eduardo.valentin@xxxxxx> > > Signed-off-by: Aaro Koskinen <aaro.koskinen@xxxxxx> > > Cc: stable@xxxxxxxxxxxxxxx > > --- > > drivers/video/omap2/displays-new/panel-sony-acx565akm.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/video/omap2/displays-new/panel-sony-acx565akm.c b/drivers/video/omap2/displays-new/panel-sony-acx565akm.c > > index e6d56f7..72fe2a8 100644 > > --- a/drivers/video/omap2/displays-new/panel-sony-acx565akm.c > > +++ b/drivers/video/omap2/displays-new/panel-sony-acx565akm.c > > @@ -616,7 +616,7 @@ static int acx565akm_enable(struct omap_dss_device *dssdev) > > > > mutex_lock(&ddata->mutex); > > r = acx565akm_panel_power_on(dssdev); > > - mutex_unlock(&ddata->mutex); > > + /* NOTE: acx565akm_panel_power_on() will unlock the mutex. */ > > > > if (r) > > return r; > > > > Hm why would you fix it like this? Why not remove the mutex_unlock from > acx565akm_panel_power_on()? Looks to me like that one is the buggy one. The unlock needs to be there because acx565akm_bl_update_status() also locks the mutex. I'll send a new version where the mutex_lock() is done inside acx565akm_panel_power_on(). A. -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html