[Intel-gfx] [PATCH 1/2] drm/i915/guc: Use correct lock for accessing guc->mmio_msg

[Tvrtko Ursulin]

From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Guc->mmio_msg is set under the guc->irq_lock in guc_get_mmio_msg so it
should be consumed under the same lock from guc_handle_mmio_msg.

I am not sure if the overall flow here makes complete sense but at least
the correct lock is now used.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
---
 drivers/gpu/drm/i915/gt/uc/intel_uc.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
index 4e6070e95fe9..220626c3ad81 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_uc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
@@ -175,19 +175,15 @@ static void guc_get_mmio_msg(struct intel_guc *guc)
 
 static void guc_handle_mmio_msg(struct intel_guc *guc)
 {
-	struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
-
 	/* we need communication to be enabled to reply to GuC */
 	GEM_BUG_ON(!guc_communication_enabled(guc));
 
-	if (!guc->mmio_msg)
-		return;
-
-	spin_lock_irq(&i915->irq_lock);
-	intel_guc_to_host_process_recv_msg(guc, &guc->mmio_msg, 1);
-	spin_unlock_irq(&i915->irq_lock);
-
-	guc->mmio_msg = 0;
+	spin_lock_irq(&guc->irq_lock);
+	if (guc->mmio_msg) {
+		intel_guc_to_host_process_recv_msg(guc, &guc->mmio_msg, 1);
+		guc->mmio_msg = 0;
+	}
+	spin_unlock_irq(&guc->irq_lock);
 }
 
 static void guc_reset_interrupts(struct intel_guc *guc)
-- 
2.25.1