3 files changed, 54 insertions, 5 deletions

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
index 861d0c58388c..27df41c53b89 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
@@ -159,6 +159,21 @@ static void gen11_disable_guc_interrupts(struct intel_guc *guc)
 	gen11_reset_guc_interrupts(guc);
 }
 
+static void guc_dead_worker_func(struct work_struct *w)
+{
+	struct intel_guc *guc = container_of(w, struct intel_guc, dead_guc_worker);
+	struct intel_gt *gt = guc_to_gt(guc);
+	unsigned long last = guc->last_dead_guc_jiffies;
+	unsigned long delta = jiffies_to_msecs(jiffies - last);
+
+	if (delta < 500) {
+		intel_gt_set_wedged(gt);
+	} else {
+		intel_gt_handle_error(gt, ALL_ENGINES, I915_ERROR_CAPTURE, "dead GuC");
+		guc->last_dead_guc_jiffies = jiffies;
+	}
+}
+
 void intel_guc_init_early(struct intel_guc *guc)
 {
 	struct intel_gt *gt = guc_to_gt(guc);
@@ -171,6 +186,8 @@ void intel_guc_init_early(struct intel_guc *guc)
 	intel_guc_slpc_init_early(&guc->slpc);
 	intel_guc_rc_init_early(guc);
 
+	INIT_WORK(&guc->dead_guc_worker, guc_dead_worker_func);
+
 	mutex_init(&guc->send_mutex);
 	spin_lock_init(&guc->irq_lock);
 	if (GRAPHICS_VER(i915) >= 11) {
@@ -449,6 +466,8 @@ void intel_guc_fini(struct intel_guc *guc)
 	if (!intel_uc_fw_is_loadable(&guc->fw))
 		return;
 
+	flush_work(&guc->dead_guc_worker);
+
 	if (intel_guc_slpc_is_used(guc))
 		intel_guc_slpc_fini(&guc->slpc);
 
@@ -573,6 +592,20 @@ out:
 	return ret;
 }
 
+int intel_guc_crash_process_msg(struct intel_guc *guc, u32 action)
+{
+	if (action == INTEL_GUC_ACTION_NOTIFY_CRASH_DUMP_POSTED)
+		guc_err(guc, "Crash dump notification\n");
+	else if (action == INTEL_GUC_ACTION_NOTIFY_EXCEPTION)
+		guc_err(guc, "Exception notification\n");
+	else
+		guc_err(guc, "Unknown crash notification: 0x%04X\n", action);
+
+	queue_work(system_unbound_wq, &guc->dead_guc_worker);
+
+	return 0;
+}
+
 int intel_guc_to_host_process_recv_msg(struct intel_guc *guc,
 				       const u32 *payload, u32 len)
 {
@@ -589,6 +622,9 @@ int intel_guc_to_host_process_recv_msg(struct intel_guc *guc,
 	if (msg & INTEL_GUC_RECV_MSG_EXCEPTION)
 		guc_err(guc, "Received early exception notification!\n");
 
+	if (msg & (INTEL_GUC_RECV_MSG_CRASH_DUMP_POSTED | INTEL_GUC_RECV_MSG_EXCEPTION))
+		queue_work(system_unbound_wq, &guc->dead_guc_worker);
+
 	return 0;
 }
 
@@ -628,6 +664,8 @@ int intel_guc_suspend(struct intel_guc *guc)
 		return 0;
 
 	if (intel_guc_submission_is_used(guc)) {
+		flush_work(&guc->dead_guc_worker);
+
 		/*
 		 * This H2G MMIO command tears down the GuC in two steps. First it will
 		 * generate a G2H CTB for every active context indicating a reset. In
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
index 8dc291ff0093..6c392bad29c1 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h
@@ -266,6 +266,20 @@ struct intel_guc {
 		unsigned long last_stat_jiffies;
 	} timestamp;
 
+	/**
+	 * @dead_guc_worker: Asynchronous worker thread for forcing a GuC reset.
+	 * Specifically used when the G2H handler wants to issue a reset. Resets
+	 * require flushing the G2H queue. So, the G2H processing itself must not
+	 * trigger a reset directly. Instead, go via this worker.
+	 */
+	struct work_struct dead_guc_worker;
+	/**
+	 * @last_dead_guc_jiffies: timestamp of previous 'dead guc' occurrance
+	 * used to prevent a fundamentally broken system from continuously
+	 * reloading the GuC.
+	 */
+	unsigned long last_dead_guc_jiffies;
+
 #ifdef CONFIG_DRM_I915_SELFTEST
 	/**
 	 * @number_guc_id_stolen: The number of guc_ids that have been stolen
@@ -476,6 +490,7 @@ int intel_guc_engine_failure_process_msg(struct intel_guc *guc,
 					 const u32 *msg, u32 len);
 int intel_guc_error_capture_process_msg(struct intel_guc *guc,
 					const u32 *msg, u32 len);
+int intel_guc_crash_process_msg(struct intel_guc *guc, u32 action);
 
 struct intel_engine_cs *
 intel_guc_lookup_engine(struct intel_guc *guc, u8 guc_class, u8 instance);
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
index 97eadd08181d..6e22af31513a 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
@@ -1112,12 +1112,8 @@ static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *r
 		ret = 0;
 		break;
 	case INTEL_GUC_ACTION_NOTIFY_CRASH_DUMP_POSTED:
-		CT_ERROR(ct, "Received GuC crash dump notification!\n");
-		ret = 0;
-		break;
 	case INTEL_GUC_ACTION_NOTIFY_EXCEPTION:
-		CT_ERROR(ct, "Received GuC exception notification!\n");
-		ret = 0;
+		ret = intel_guc_crash_process_msg(guc, action);
 		break;
 	default:
 		ret = -EOPNOTSUPP;