bug in metal: offset is stored as uint32, overflow (#15129)

* metal uint32 icb offset overflow

* fix: diff

* supports_exec_item

* GraphRunner.supports_exec_item

* tests

* fix: can't import on non-metal

test/unit/test_metal_graph.py

@@ -0,0 +1,26 @@
+import unittest
+from unittest.mock import MagicMock
+from tinygrad import Device
+from tinygrad.engine.realize import CompiledRunner
+
+def _ei(*offsets):
+  ei = MagicMock()
+  ei.prg = MagicMock(spec=CompiledRunner)
+  ei.bufs = [None if o is None else MagicMock(**{"_buf.offset": o}) for o in offsets]
+  return ei
+
+@unittest.skipUnless(Device.DEFAULT == "METAL", "Metal device required to run")
+class TestMetalGraph(unittest.TestCase):
+  def setUp(self):
+    from tinygrad.runtime.graph.metal import MetalGraph
+    self.MetalGraph = MetalGraph
+    self.dev = Device[Device.DEFAULT]
+
+  def test_supports_exec_item_normal_offset(self):
+    assert self.MetalGraph.supports_exec_item([self.dev], _ei(0, 100, 0xFFFFFFFF)) is True
+
+  def test_supports_exec_item_overflow_offset(self):
+    assert self.MetalGraph.supports_exec_item([], _ei(0, 0x100000000)) is False
+
+if __name__ == "__main__":
+  unittest.main()

tinygrad/runtime/graph/metal.py

@@ -13,7 +13,6 @@ class MetalGraph(GraphRunner):
   def __init__(self, jit_cache: list[ExecItem], input_buffers: list[Buffer], var_vals: dict[str, int],
                orig_valid_positions: dict[int, set[int]]|None = None):
     super().__init__(jit_cache, input_buffers, var_vals, orig_valid_positions)
-    if not all(isinstance(ji.prg, CompiledRunner) for ji in jit_cache): raise GraphException
 
     # create metal batch exec
     icb_descriptor = metal.MTLIndirectCommandBufferDescriptor.new()
@@ -109,3 +108,9 @@ class MetalGraph(GraphRunner):
     if PROFILE and self.command_buffer is not None:
       wait_check(self.command_buffer)
       self.collect_timestamps()
+
+  @staticmethod
+  def supports_exec_item(devs, ei:ExecItem) -> bool:
+    # Metal ICB replay encodes offsets as uint32; reject if any buffer offset exceeds 32-bit range.
+    if any(b is not None and b._buf.offset > 0xFFFFFFFF for b in ei.bufs): return False
+    return GraphRunner.supports_exec_item(devs, ei)