diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-04-09 16:44:15 +0200 |
---|---|---|
committer | Jani Nikula <jani.nikula@intel.com> | 2015-04-10 14:29:27 +0300 |
commit | 9da7d69357389ea63893434fe3b17b9fbc2c2d2d (patch) | |
tree | 6ef4b8b6cc08a3b62915c3d95585fadd2db8a839 /drivers/gpu/drm/i915 | |
parent | 6e0aa8018f9c676b115b7ca6c20a056fc57c68a9 (diff) | |
download | linux-9da7d69357389ea63893434fe3b17b9fbc2c2d2d.tar.bz2 |
drm/i915: Fix locking in DRRS flush/invalidate hooks
We must acquire the mutex before we can check drrs.dp, otherwise
someone might sneak in with a modeset, clear the pointer after we've
checked it and then the code will Oops.
This issue has been introduced in
commit a93fad0f7fb8a3ff12e8814b630648f6d187954c
Author: Vandana Kannan <vandana.kannan@intel.com>
Date: Sat Jan 10 02:25:59 2015 +0530
drm/i915: DRRS calls based on frontbuffer
v2: Don't blow up on uninitialized mutex and work item by checking
whether DRRS is support or not first. Also unconditionally initialize
the mutex/work item to avoid future trouble.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Vandana Kannan <vandana.kannan@intel.com>
Cc: stable@vger.kernel.org (4.0+ only)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915')
-rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index b70e635ccaf4..5e60473d08fe 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -5157,7 +5157,6 @@ static void intel_edp_drrs_downclock_work(struct work_struct *work) downclock_mode->vrefresh); unlock: - mutex_unlock(&dev_priv->drrs.mutex); } @@ -5179,12 +5178,17 @@ void intel_edp_drrs_invalidate(struct drm_device *dev, struct drm_crtc *crtc; enum pipe pipe; - if (!dev_priv->drrs.dp) + if (dev_priv->drrs.type == DRRS_NOT_SUPPORTED) return; cancel_delayed_work_sync(&dev_priv->drrs.work); mutex_lock(&dev_priv->drrs.mutex); + if (!dev_priv->drrs.dp) { + mutex_unlock(&dev_priv->drrs.mutex); + return; + } + crtc = dp_to_dig_port(dev_priv->drrs.dp)->base.base.crtc; pipe = to_intel_crtc(crtc)->pipe; @@ -5218,12 +5222,17 @@ void intel_edp_drrs_flush(struct drm_device *dev, struct drm_crtc *crtc; enum pipe pipe; - if (!dev_priv->drrs.dp) + if (dev_priv->drrs.type == DRRS_NOT_SUPPORTED) return; cancel_delayed_work_sync(&dev_priv->drrs.work); mutex_lock(&dev_priv->drrs.mutex); + if (!dev_priv->drrs.dp) { + mutex_unlock(&dev_priv->drrs.mutex); + return; + } + crtc = dp_to_dig_port(dev_priv->drrs.dp)->base.base.crtc; pipe = to_intel_crtc(crtc)->pipe; dev_priv->drrs.busy_frontbuffer_bits &= ~frontbuffer_bits; @@ -5294,6 +5303,9 @@ intel_dp_drrs_init(struct intel_connector *intel_connector, struct drm_i915_private *dev_priv = dev->dev_private; struct drm_display_mode *downclock_mode = NULL; + INIT_DELAYED_WORK(&dev_priv->drrs.work, intel_edp_drrs_downclock_work); + mutex_init(&dev_priv->drrs.mutex); + if (INTEL_INFO(dev)->gen <= 6) { DRM_DEBUG_KMS("DRRS supported for Gen7 and above\n"); return NULL; @@ -5312,10 +5324,6 @@ intel_dp_drrs_init(struct intel_connector *intel_connector, return NULL; } - INIT_DELAYED_WORK(&dev_priv->drrs.work, intel_edp_drrs_downclock_work); - - mutex_init(&dev_priv->drrs.mutex); - dev_priv->drrs.type = dev_priv->vbt.drrs_type; dev_priv->drrs.refresh_rate_type = DRRS_HIGH_RR; |