[Mesa-dev] [PATCH] r600g: fix crash in set_framebuffer_state

[Grigori Goronzy]

We should be able to safely set the framebuffer state without a
fragment shader bound. bind_ps_state will take care of updating the
necessary state bits later.

v2: check in update_db_shader_control
---
 src/gallium/drivers/r600/evergreen_state.c | 23 +++++++++++++++--------
 src/gallium/drivers/r600/r600_state.c      | 15 +++++++++++----
 2 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/src/gallium/drivers/r600/evergreen_state.c b/src/gallium/drivers/r600/evergreen_state.c
index 83cb024..4535d21 100644
--- a/src/gallium/drivers/r600/evergreen_state.c
+++ b/src/gallium/drivers/r600/evergreen_state.c
@@ -3581,14 +3581,21 @@ void *evergreen_create_db_flush_dsa(struct r600_context *rctx)
 
 void evergreen_update_db_shader_control(struct r600_context * rctx)
 {
-	bool dual_export = rctx->framebuffer.export_16bpc &&
-			   !rctx->ps_shader->current->ps_depth_export;
-
-	unsigned db_shader_control = rctx->ps_shader->current->db_shader_control |
-			S_02880C_DUAL_EXPORT_ENABLE(dual_export) |
-			S_02880C_DB_SOURCE_FORMAT(dual_export ? V_02880C_EXPORT_DB_TWO :
-								V_02880C_EXPORT_DB_FULL) |
-			S_02880C_ALPHA_TO_MASK_DISABLE(rctx->framebuffer.cb0_is_integer);
+	bool dual_export;
+	unsigned db_shader_control;
+
+	if (!rctx->ps_shader) {
+		return;
+	}
+
+	dual_export = rctx->framebuffer.export_16bpc &&
+		      !rctx->ps_shader->current->ps_depth_export;
+
+	db_shader_control = rctx->ps_shader->current->db_shader_control |
+			    S_02880C_DUAL_EXPORT_ENABLE(dual_export) |
+			    S_02880C_DB_SOURCE_FORMAT(dual_export ? V_02880C_EXPORT_DB_TWO :
+								    V_02880C_EXPORT_DB_FULL) |
+			    S_02880C_ALPHA_TO_MASK_DISABLE(rctx->framebuffer.cb0_is_integer);
 
 	/* When alpha test is enabled we can't trust the hw to make the proper
 	 * decision on the order in which ztest should be run related to fragment
diff --git a/src/gallium/drivers/r600/r600_state.c b/src/gallium/drivers/r600/r600_state.c
index b01ab9c..f148052 100644
--- a/src/gallium/drivers/r600/r600_state.c
+++ b/src/gallium/drivers/r600/r600_state.c
@@ -2972,11 +2972,18 @@ void *r600_create_db_flush_dsa(struct r600_context *rctx)
 
 void r600_update_db_shader_control(struct r600_context * rctx)
 {
-	bool dual_export = rctx->framebuffer.export_16bpc &&
-			   !rctx->ps_shader->current->ps_depth_export;
+	bool dual_export;
+	unsigned db_shader_control;
 
-	unsigned db_shader_control = rctx->ps_shader->current->db_shader_control |
-				     S_02880C_DUAL_EXPORT_ENABLE(dual_export);
+	if (!rctx->ps_shader) {
+		return;
+	}
+
+	dual_export = rctx->framebuffer.export_16bpc &&
+		      !rctx->ps_shader->current->ps_depth_export;
+
+	db_shader_control = rctx->ps_shader->current->db_shader_control |
+			    S_02880C_DUAL_EXPORT_ENABLE(dual_export);
 
 	/* When alpha test is enabled we can't trust the hw to make the proper
 	 * decision on the order in which ztest should be run related to fragment
-- 
1.8.1.2