netdev - Queries regarding TAP interface

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Message-ID: <C7C039BE-EDC9-4E82-BC66-EEDE814F9E56@cavium.com>
Date:   Fri, 12 May 2017 05:02:37 +0000
From:   "Kashyap, Saurav" <Saurav.Kashyap@...ium.com>
To:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Queries regarding TAP interface

Hi,

I am using upstream kernel 4.11.0 and base is RHEL 7.2. I am playing around with TAP devices and created it using following commands
=======
ip tuntap add tap10 mode tap
ip addr add 172.28.12.1/24 dev tap10
ip link set tap10 up
ethtool -s tap10 msglvl 1
=======

I enabled debug in driver and also added some prints in tun_net_xmit function. I tried to ping using tap10 but I don’t see request reaching driver. I also tried to create a bridge using brctl and link with physical ethernet interface but it didn’t work.

Second experiment I did was to create two tap device on same system and try pinging one from another, that also didn’t worked. 
I have following queries
1) Is I am missing something? 
2) Is is possible to hook my own tx/rx to that tap device, so that data packets actually goes on wire?
3) Does DHCP works with tap devices?

Thanks,
~Saurav