Repository: pytorch
Issue: cannot run mobilenet_v2_quantized on pytorch/caffe2
Labels: caffe2

## ❓ Questions and Help
I am trying to run mobilenet_v2_quantized (https://github.com/caffe2/models/tree/master/mobilenet_v2_quantized) on pytorch/caffe2 repo which supports int8 .

after compiling pytorch on tx2 and run the model, I meet the following error:

```
WARNING:root:This caffe2 python run does not have GPU support. Will run in CPU only mode.
WARNING:caffe2.python.workspace:Original python traceback for operator `-2110861432` in network `mobilenet_v2_quant` in exception above (most recent call last):
Traceback (most recent call last):
  File "test_caffe2.py", line 470, in <module>
    net_def = createNet(pred_net)
  File "test_caffe2.py", line 406, in createNet
    workspace.CreateNet(net_def, overwrite=True)
  File "/home/gg/pytorch/build/caffe2/python/workspace.py", line 154, in CreateNet
    StringifyProto(net), overwrite,
  File "/home/gg/pytorch/build/caffe2/python/workspace.py", line 180, in CallWithExceptionIntercept
    return func(*args, **kwargs)
RuntimeError: [enforce fail at operator.cc:46] blob != nullptr. op NCHW2NHWC: Encountered a non-existing input blob: data
frame #0: c10::ThrowEnforceNotMet(char const*, int, char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, void const*) + 0x7c (0x7f5ac89ed4 in /home/gg/pytorch/build/lib/libc10.so)
frame #1: caffe2::OperatorBase::OperatorBase(caffe2::OperatorDef const&, caffe2::Workspace*) + 0x560 (0x7f5bc5fa18 in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #2: <unknown function> + 0x13e5efc (0x7f5c088efc in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #3: std::_Function_handler<std::unique_ptr<caffe2::OperatorBase, std::default_delete<caffe2::OperatorBase> > (caffe2::OperatorDef const&, caffe2::Workspace*), std::unique_ptr<caffe2::OperatorBase, std::default_delete<caffe2::OperatorBase> > (*)(caffe2::OperatorDef const&, caffe2::Workspace*)>::_M_invoke(std::_Any_data const&, caffe2::OperatorDef const&, caffe2::Workspace*&&) + 0x34 (0x7f5cb5dd9c in /home/gg/pytorch/build/caffe2/python/caffe2_pybind11_state.cpython-35m-aarch64-linux-gnu.so)
frame #4: <unknown function> + 0xfbacfc (0x7f5bc5dcfc in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #5: <unknown function> + 0xfbcd0c (0x7f5bc5fd0c in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #6: caffe2::CreateOperator(caffe2::OperatorDef const&, caffe2::Workspace*, int) + 0x430 (0x7f5bc60898 in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #7: caffe2::SimpleNet::SimpleNet(std::shared_ptr<caffe2::NetDef const> const&, caffe2::Workspace*) + 0x3dc (0x7f5bcc016c in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #8: <unknown function> + 0x101eb3c (0x7f5bcc1b3c in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #9: <unknown function> + 0xfa5904 (0x7f5bc48904 in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #10: caffe2::CreateNet(std::shared_ptr<caffe2::NetDef const> const&, caffe2::Workspace*) + 0x90c (0x7f5bc98f94 in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #11: caffe2::Workspace::CreateNet(std::shared_ptr<caffe2::NetDef const> const&, bool) + 0x1e4 (0x7f5bcab824 in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #12: caffe2::Workspace::CreateNet(caffe2::NetDef const&, bool) + 0xa4 (0x7f5bcaca7c in /home/gg/pytorch/build/lib/libcaffe2.so)
frame #13: <unknown function> + 0x51060 (0x7f5cb55060 in /home/gg/pytorch/build/caffe2/python/caffe2_pybind11_state.cpython-35m-aarch64-linux-gnu.so)
frame #14: <unknown function> + 0x512d0 (0x7f5cb552d0 in /home/gg/pytorch/build/caffe2/python/caffe2_pybind11_state.cpython-35m-aarch64-linux-gnu.so)
frame #15: <unknown function> + 0x8edfc (0x7f5cb92dfc in /home/gg/pytorch/build/caffe2/python/caffe2_pybind11_state.cpython-35m-aarch64-linux-gnu.so)
<omitting python frames>


```
the model is running on CPU only
what is the problem?