From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aaro Koskinen Date: Wed, 27 Nov 2013 21:32:45 +0000 Subject: [PATCH RESEND v2] ARM: OMAPFB: panel-sony-acx565akm: fix bad unlock balance Message-Id: <1385587965-4612-1-git-send-email-aaro.koskinen@iki.fi> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tomi Valkeinen , linux-omap@vger.kernel.org, linux-fbdev@vger.kernel.org Cc: Eduardo Valentin , Aaro Koskinen , stable@vger.kernel.org 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] [] acx565akm_enable+0x12c/0x18c [ 7.335998] but there are no more locks to release! Fix by removing double unlock and handling the locking completely inside acx565akm_panel_power_on() when doing the power on. Reported-by: Eduardo Valentin Signed-off-by: Aaro Koskinen Cc: stable@vger.kernel.org --- drivers/video/omap2/displays-new/panel-sony-acx565akm.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/video/omap2/displays-new/panel-sony-acx565akm.c b/drivers/video/omap2/displays-new/panel-sony-acx565akm.c index e6d56f7..d94f35d 100644 --- a/drivers/video/omap2/displays-new/panel-sony-acx565akm.c +++ b/drivers/video/omap2/displays-new/panel-sony-acx565akm.c @@ -526,6 +526,8 @@ static int acx565akm_panel_power_on(struct omap_dss_device *dssdev) struct omap_dss_device *in = ddata->in; int r; + mutex_lock(&ddata->mutex); + dev_dbg(&ddata->spi->dev, "%s\n", __func__); in->ops.sdi->set_timings(in, &ddata->videomode); @@ -614,10 +616,7 @@ static int acx565akm_enable(struct omap_dss_device *dssdev) if (omapdss_device_is_enabled(dssdev)) return 0; - mutex_lock(&ddata->mutex); r = acx565akm_panel_power_on(dssdev); - mutex_unlock(&ddata->mutex); - if (r) return r; -- 1.8.4.3