Testing NVMe async commands

[Arka Sharma <arka.sw1988@gmail.com>]

We have developed an application to test the async flow in
NvmExpressDxe. We have allocated a buffer of size 8 MB and in that
buffer we are reading 128k chunks, which results in 64 commands as the
async submission queue depth is 64, after calling passthru with the
Event we increment a counter and inside the notification function we
decrement the counter. After sending all the commands we wait till the
counter becomes 0. After 64 reads are completed we issue 64 write
command passing the buffer we have just read. So after 8 MB is done we
increment the lba and repeat the same. In the application we are
putting the starting lba of each 8 mb operation, so it increments as
0x0, 0x4000, 0x8000 as lba size of the device is 512 bytes. We are
observing a hang at lba 0x66E4000, after processing 210720 commands.
We are creating and closing the events after each 8 MB read and write.
This stuck is seen consistently. May be there is something wrong we
are doing in the application.

Please let me know if there is any reference UEFI application to test async ?