msm: camera: isp: Check whether flush list is empty

We will get invalid req from flush_list if the
flush list is empty when we get each req by
list API list_for_each_entry_safe. This change
checks whether flush list is empty before
accessing this list.

CRs-Fixed: 2885145
Change-Id: I9b2828b03706a0f7412828905cc0a9e28d15fd76
Signed-off-by: Depeng Shao <depengs@codeaurora.org>

drivers/cam_isp/cam_isp_context.c

@@ -3542,6 +3542,17 @@ static int __cam_isp_ctx_flush_req(struct cam_context *ctx,
 			CAM_ISP_STATE_CHANGE_TRIGGER_FLUSH, req->request_id);
 	}
 
+	if (list_empty(&flush_list)) {
+		/*
+		 * Maybe the req isn't sent to KMD since UMD already skip
+		 * req in CSL layer.
+		 */
+		CAM_INFO(CAM_ISP,
+			"flush list is empty, flush type %d for req %llu",
+			flush_req->type, flush_req->req_id);
+		return 0;
+	}
+
 	list_for_each_entry_safe(req, req_temp, &flush_list, list) {
 		req_isp = (struct cam_isp_ctx_req *) req->req_priv;
 		for (i = 0; i < req_isp->num_fence_map_out; i++) {
@@ -3567,12 +3578,6 @@ static int __cam_isp_ctx_flush_req(struct cam_context *ctx,
 		list_add_tail(&req->list, &ctx->free_req_list);
 	}
 
-	if (flush_req->type == CAM_REQ_MGR_FLUSH_TYPE_CANCEL_REQ &&
-		!cancel_req_id_found)
-		CAM_DBG(CAM_ISP,
-			"Flush request id:%lld is not found in the list",
-			flush_req->req_id);
-
 	return 0;
 }