Commit f0ad62a6 authored by José Roberto de Souza's avatar José Roberto de Souza
Browse files

drm/i915/psr: Get pipe id following atomic guidelines 

As stated in struct drm_encoder, crtc field should only be used
by non-atomic drivers.

So here caching the pipe id in intel_psr_enable() what is way more
simple and efficient than at every call to
intel_psr_flush()/invalidate() get the
drm.mode_config.connection_mutex lock to safely be able to get the
pipe id by reading drm_connector_state.crtc.

This should fix the null pointer dereference crash below as the
previous way to get the pipe id was prone to race conditions.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105959


Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: default avatarJosé Roberto de Souza <jose.souza@intel.com>
Reviewed-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181128072838.22773-1-jose.souza@intel.com
parent b9f78d67

drivers/gpu/drm/i915/i915_drv.h

+1 −0
Original line number Diff line number Diff line
@@ -495,6 +495,7 @@ struct i915_psr { 
	bool sink_support;

	bool prepared, enabled;

	struct intel_dp *dp;

	enum pipe pipe;

	bool active;

	struct work_struct work;

	unsigned busy_frontbuffer_bits;

drivers/gpu/drm/i915/intel_psr.c

+4 −15
Original line number Diff line number Diff line
@@ -719,6 +719,7 @@ void intel_psr_enable(struct intel_dp *intel_dp, 
	dev_priv->psr.psr2_enabled = intel_psr2_enabled(dev_priv, crtc_state);

	dev_priv->psr.busy_frontbuffer_bits = 0;

	dev_priv->psr.prepared = true;

	dev_priv->psr.pipe = to_intel_crtc(crtc_state->base.crtc)->pipe;



	if (psr_global_enabled(dev_priv->psr.debug))

		intel_psr_enable_locked(dev_priv, crtc_state);
@@ -1026,9 +1027,6 @@ unlock: 
void intel_psr_invalidate(struct drm_i915_private *dev_priv,

			  unsigned frontbuffer_bits, enum fb_op_origin origin)

{

	struct drm_crtc *crtc;

	enum pipe pipe;



	if (!CAN_PSR(dev_priv))

		return;
@@ -1041,10 +1039,7 @@ void intel_psr_invalidate(struct drm_i915_private *dev_priv, 
		return;

	}



	crtc = dp_to_dig_port(dev_priv->psr.dp)->base.base.crtc;

	pipe = to_intel_crtc(crtc)->pipe;



	frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);

	frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(dev_priv->psr.pipe);

	dev_priv->psr.busy_frontbuffer_bits |= frontbuffer_bits;



	if (frontbuffer_bits)
@@ -1069,9 +1064,6 @@ void intel_psr_invalidate(struct drm_i915_private *dev_priv, 
void intel_psr_flush(struct drm_i915_private *dev_priv,

		     unsigned frontbuffer_bits, enum fb_op_origin origin)

{

	struct drm_crtc *crtc;

	enum pipe pipe;



	if (!CAN_PSR(dev_priv))

		return;
@@ -1084,10 +1076,7 @@ void intel_psr_flush(struct drm_i915_private *dev_priv, 
		return;

	}



	crtc = dp_to_dig_port(dev_priv->psr.dp)->base.base.crtc;

	pipe = to_intel_crtc(crtc)->pipe;



	frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);

	frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(dev_priv->psr.pipe);

	dev_priv->psr.busy_frontbuffer_bits &= ~frontbuffer_bits;



	/* By definition flush = invalidate + flush */
@@ -1101,7 +1090,7 @@ void intel_psr_flush(struct drm_i915_private *dev_priv, 
		 * but it makes more sense write to the current active

		 * pipe.

		 */

		I915_WRITE(CURSURFLIVE(pipe), 0);

		I915_WRITE(CURSURFLIVE(dev_priv->psr.pipe), 0);

	}



	if (!dev_priv->psr.active && !dev_priv->psr.busy_frontbuffer_bits)

CRA Git | Maintained and supported by SUSTech CRA and CCSE