fix: skip incompatible LoRA weights (#1825)

src/model/adapter/lora.hpp

@@ -14,6 +14,8 @@ struct LoraModel : public GGMLRunner {
     std::unordered_map<std::string, ggml_tensor*> lora_tensors;
     std::map<ggml_tensor*, ggml_tensor*> original_tensor_to_final_tensor;
     std::set<std::string> applied_lora_tensors;
+    std::set<std::string> skipped_incompatible_lora_tensors;
+    std::set<std::string> warned_incompatible_model_tensors;
     std::string file_path;
     std::shared_ptr<ModelManager> model_manager;
     ggml_backend_t params_backend = nullptr;
@@ -133,6 +135,8 @@ struct LoraModel : public GGMLRunner {
         lora_tensors.clear();
         original_tensor_to_final_tensor.clear();
         applied_lora_tensors.clear();
+        skipped_incompatible_lora_tensors.clear();
+        warned_incompatible_model_tensors.clear();
         applied             = false;
         tensor_preprocessed = false;
     }
@@ -546,7 +550,27 @@ struct LoraModel : public GGMLRunner {
                 }
             }
 
-            GGML_ASSERT(ggml_nelements(diff) == ggml_nelements(model_tensor));
+            if (ggml_nelements(diff) != ggml_nelements(model_tensor)) {
+                const std::string lora_tensor_prefix = "lora." + model_tensor_name + ".";
+                for (const auto& tensor_name : applied_lora_tensors) {
+                    if (starts_with(tensor_name, lora_tensor_prefix)) {
+                        skipped_incompatible_lora_tensors.insert(tensor_name);
+                    }
+                }
+                if (warned_incompatible_model_tensors.insert(model_tensor_name).second) {
+                    LOG_WARN("skip incompatible LoRA tensor |%s|: model shape = [%lld, %lld, %lld, %lld], LoRA shape = [%lld, %lld, %lld, %lld]",
+                             model_tensor_name.c_str(),
+                             static_cast<long long>(model_tensor->ne[0]),
+                             static_cast<long long>(model_tensor->ne[1]),
+                             static_cast<long long>(model_tensor->ne[2]),
+                             static_cast<long long>(model_tensor->ne[3]),
+                             static_cast<long long>(diff->ne[0]),
+                             static_cast<long long>(diff->ne[1]),
+                             static_cast<long long>(diff->ne[2]),
+                             static_cast<long long>(diff->ne[3]));
+                }
+                return nullptr;
+            }
             diff = ggml_reshape(ctx, diff, model_tensor);
         }
         return diff;
@@ -555,6 +579,7 @@ struct LoraModel : public GGMLRunner {
     ggml_tensor* get_out_diff(ggml_context* ctx,
                               ggml_backend_t backend,
                               ggml_tensor* x,
+                              ggml_tensor* model_weight,
                               WeightAdapter::ForwardParams forward_params,
                               const std::string& model_tensor_name) {
         ggml_tensor* out_diff = nullptr;
@@ -707,6 +732,43 @@ struct LoraModel : public GGMLRunner {
                 break;
             }
 
+            if (!is_conv2d) {
+                const int64_t down_in  = lora_down->ne[0];
+                const int64_t down_out = lora_down->ne[1];
+                const int64_t up_in    = lora_up->ne[0];
+                const int64_t up_out   = lora_up->ne[1];
+
+                bool compatible = down_in == model_weight->ne[0] &&
+                                  up_out == model_weight->ne[1];
+                if (lora_mid != nullptr) {
+                    compatible = compatible &&
+                                 lora_mid->ne[0] == down_out &&
+                                 up_in == lora_mid->ne[1];
+                } else {
+                    compatible = compatible && up_in == down_out;
+                }
+
+                if (!compatible) {
+                    skipped_incompatible_lora_tensors.insert(lora_down_name);
+                    skipped_incompatible_lora_tensors.insert(lora_up_name);
+                    skipped_incompatible_lora_tensors.insert(lora_mid_name);
+                    skipped_incompatible_lora_tensors.insert(scale_name);
+                    skipped_incompatible_lora_tensors.insert(alpha_name);
+                    if (warned_incompatible_model_tensors.insert(model_tensor_name).second) {
+                        LOG_WARN("skip incompatible LoRA tensor |%s|: model shape = [%lld, %lld], down shape = [%lld, %lld], up shape = [%lld, %lld]",
+                                 model_tensor_name.c_str(),
+                                 static_cast<long long>(model_weight->ne[0]),
+                                 static_cast<long long>(model_weight->ne[1]),
+                                 static_cast<long long>(down_in),
+                                 static_cast<long long>(down_out),
+                                 static_cast<long long>(up_in),
+                                 static_cast<long long>(up_out));
+                    }
+                    index++;
+                    continue;
+                }
+            }
+
             applied_lora_tensors.insert(lora_up_name);
             applied_lora_tensors.insert(lora_down_name);
 
@@ -869,10 +931,13 @@ struct LoraModel : public GGMLRunner {
     void stat(bool at_runntime = false) {
         size_t total_lora_tensors_count   = 0;
         size_t applied_lora_tensors_count = 0;
+        size_t skipped_lora_tensors_count = 0;
 
         for (auto& kv : lora_tensors) {
             total_lora_tensors_count++;
-            if (applied_lora_tensors.find(kv.first) == applied_lora_tensors.end()) {
+            if (skipped_incompatible_lora_tensors.find(kv.first) != skipped_incompatible_lora_tensors.end()) {
+                skipped_lora_tensors_count++;
+            } else if (applied_lora_tensors.find(kv.first) == applied_lora_tensors.end()) {
                 if (!at_runntime) {
                     LOG_WARN("unused lora tensor |%s|", kv.first.c_str());
                     print_ggml_tensor(kv.second, true);
@@ -884,12 +949,17 @@ struct LoraModel : public GGMLRunner {
         /* Don't worry if this message shows up twice in the logs per LoRA,
          * this function is called once to calculate the required buffer size
          * and then again to actually generate a graph to be used */
-        if (!at_runntime && applied_lora_tensors_count != total_lora_tensors_count) {
+        size_t compatible_lora_tensors_count = total_lora_tensors_count - skipped_lora_tensors_count;
+        if (!at_runntime && applied_lora_tensors_count != compatible_lora_tensors_count) {
             LOG_WARN("Only (%lu / %lu) LoRA tensors have been applied, lora_file_path = %s",
-                     applied_lora_tensors_count, total_lora_tensors_count, file_path.c_str());
+                     applied_lora_tensors_count, compatible_lora_tensors_count, file_path.c_str());
         } else {
             LOG_INFO("(%lu / %lu) LoRA tensors have been applied, lora_file_path = %s",
-                     applied_lora_tensors_count, total_lora_tensors_count, file_path.c_str());
+                     applied_lora_tensors_count, compatible_lora_tensors_count, file_path.c_str());
+        }
+        if (skipped_lora_tensors_count > 0) {
+            LOG_WARN("(%lu / %lu) incompatible LoRA tensors have been skipped, lora_file_path = %s",
+                     skipped_lora_tensors_count, total_lora_tensors_count, file_path.c_str());
         }
     }
 };
@@ -953,7 +1023,7 @@ public:
                                    forward_params.conv2d.scale);
         }
         for (auto& lora_model : lora_models) {
-            ggml_tensor* out_diff = lora_model->get_out_diff(ctx, backend, x, forward_params, prefix + "weight");
+            ggml_tensor* out_diff = lora_model->get_out_diff(ctx, backend, x, w, forward_params, prefix + "weight");
             if (out_diff == nullptr) {
                 continue;
             }