Add CuTeDSL warmup + CUDA sync after JIT compilation

CuTeDSL cute.compile corrupts GPU memory. Add warmup forward +
torch.cuda.synchronize() + health check after finalize_weights,
matching the MoE runner pattern.

vllm/kernels/linear/nvfp4/cutedsl.py

@@ -188,6 +188,21 @@ class CuTeDSLNvFp4LinearKernel(NvFp4LinearKernel):
         layer._cutedsl_global_scale_b = runner._gsb
         layer._cutedsl_activation_global_scale = activation_global_scale
 
+        # Warmup: CuTeDSL cute.compile corrupts GPU memory during JIT.
+        # Run a warmup forward to trigger compilation, then synchronize
+        # and verify GPU health. Matches cutedsl/runner.py MoE pattern.
+        with torch.no_grad():
+            warmup_x = torch.randn(1, in_features, dtype=torch.bfloat16,
+                                    device=device)
+            _ = torch.ops.cutedsl.nvfp4_linear(
+                warmup_x, runner._mat_b, runner._scale_b, runner._gsb,
+                activation_global_scale,
+            )
+            torch.cuda.synchronize()
+            # Verify GPU is still healthy after CuTeDSL JIT
+            test = torch.ones(1, device=device) + torch.ones(1, device=device)
+            assert test.item() == 2.0, "GPU corruption after CuTeDSL JIT"
+
         # Replace weight with dummy BF16 (vLLM module introspection may need it)
         layer.weight = torch.nn.Parameter(
             torch.zeros(out_features, in_features, dtype=torch.bfloat16,