[diffusion] fix: fix corrupted image editing outputs in Multi-GPU SP mode for FLUX.2-klein models (#19454)

python/sglang/multimodal_gen/test/server/perf_baselines.json

@@ -2051,6 +2051,26 @@
             "expected_e2e_ms": 6359.87,
             "expected_avg_denoise_ms": 99.47,
             "expected_median_denoise_ms": 100.27
+        },
+        "flux_2_klein_ti2i_2_gpus": {
+            "stages_ms": {
+                "InputValidationStage": 40.19,
+                "TextEncodingStage": 88.84,
+                "ImageVAEEncodingStage": 80.81,
+                "LatentPreparationStage": 1.05,
+                "TimestepPreparationStage": 28.64,
+                "DenoisingStage": 354.04,
+                "DecodingStage": 11.11
+            },
+            "denoise_step_ms": {
+                "0": 33.54,
+                "1": 61.3,
+                "2": 86.9,
+                "3": 87.55
+            },
+            "expected_e2e_ms": 716.81,
+            "expected_avg_denoise_ms": 67.32,
+            "expected_median_denoise_ms": 74.1
         }
     }
 }

python/sglang/multimodal_gen/test/server/test_server_utils.py

@@ -932,8 +932,9 @@ def get_generate_fn(
             if is_image_url(image_path):
                 new_image_paths.append(download_image_from_url(str(image_path)))
             else:
-                new_image_paths.append(Path(image_path))
-                if not image_path.exists():
+                local_path = Path(image_path)
+                new_image_paths.append(local_path)
+                if not local_path.exists():
                     pytest.skip(f"{case_id}: file missing: {image_path}")
 
         image_paths = new_image_paths

python/sglang/multimodal_gen/test/server/testcase_configs.py

@@ -790,6 +790,15 @@ TWO_GPU_CASES_B = [
         ),
         T2I_sampling_params,
     ),
+    DiffusionTestCase(
+        "flux_2_klein_ti2i_2_gpus",
+        DiffusionServerArgs(
+            model_path="black-forest-labs/FLUX.2-klein-4B",
+            modality="image",
+            num_gpus=2,
+        ),
+        TI2I_sampling_params,
+    ),
 ]
 
 # Load global configuration