ROCm: ROCm OpenCL: kernel hangs with read_imageui() call

So, having some difficulties getting my kernels to run.

My program flow works like this:

1. map an opencl image, and create map completion event MAP_COMPLETION_EVENT
2. also unmap the same image, but the unmap call waits on user event USER_EVENT, and creates an unmap completion event UNMAP_COMPLETION_EVENT
3. when I receive the MAP_COMPLETION_EVENT event, copy data to mapped pointer and then set USER_EVENT
4. this will trigger the actual unmap, which will then set UNMAP_COMPLETION_EVENT
5. the kernel that uses the above image is enqueued but waits for UNMAP_COMPLETION_EVENT

I verified that I get as far as step 4 (the image is indeed unmapped and sends the event) but the kernel never actually runs.

What is best way of trouble shooting this ?

Also, I do enqueue a large number of kernels, but they will not run until they get their UNMAP_COMPLETION_EVENT events.