netdev - Hardware time stamping support for AF

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 10 Nov 2020 22:44:12 +0000
From:   "Patel, Vedang" <vedang.patel@...el.com>
To:     Saeed Mahameed <saeed@...nel.org>,
        Jesper Dangaard Brouer <jbrouer@...hat.com>
CC:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "Gomes, Vinicius" <vinicius.gomes@...el.com>,
        "Guedes, Andre" <andre.guedes@...el.com>
Subject: Hardware time stamping support for AF_XDP applications

[Sorry if you got the email twice. Resending because it was rejected by netdev for containing HTML]

Hi Saeed/Jesper, 

I am working in the Time Sensitive Networking team at Intel. We work on implementing and upstreaming support for TSN related features for intel based NICs. Recently we have been adding support for XDP in i225. One of the features which we want to add support for is passing the hardware timestamp information to the userspace application running AF_XDP sockets (for both Tx and Rx). I came across the XDP Workshop[1] conducted in July 2020 and there you stated that you are already working on adding support for BTF based metadata to pass hardware hints for XDP Programs. My understanding (along with a few questions) of the current state is: 
* This feature is currently being maintained out of tree. I found that an RFC Series[2] was posted in June 2018. Are you planning to post an updated version to be merged in the mainline anytime soon? 
* I am guessing hardware timestamp is one of the metadata fields which will be eventually supported? [3]
* The Metadata support will be extended to pass on the hardware hints to AF_XDP sockets. Are there any rough plans on what metadata will be transferred?
* The current plan for Tx side only includes passing data from the application to the driver. Are there any plans to support passing information (like HW TX timestamp) from driver to the Application?

Finally, is there any way I can help in expediting the development and upstreaming of this feature? I have been working on studying how XDP works and can work on implementing some part of this feature if you would like.

Thanks,
Vedang Patel
Software Engineer
Intel Corporation

[1] - https://netdevconf.info/0x14/session.html?workshop-XDP
[2] - https://patchwork.ozlabs.org/project/netdev/cover/20180627024615.17856-1-saeedm@mellanox.com/
[3] - https://xdp-project.net/#outline-container-Important-medium-term-tasks