Hi,
Regarding the blocking implementation of send, there is no bug, but expected behavior. When the tx queue is full in the device, the host will be blocked, and therefore, recv will not be called. Since recv is not called, rx queue gets full, which might lead to sock inactivity timeout if tx is blocked for too long.
Thank you for the logs that you sent. I will review them now and feedback.
Regards,
Tomer