On 2/4/25 7:06 PM, Stanislav Fomichev wrote: > On 02/04, Mina Almasry wrote: >> On Tue, Feb 4, 2025 at 4:32 AM Paolo Abeni <pabeni@xxxxxxxxxx> wrote: >>> >>> On 2/3/25 11:39 PM, Mina Almasry wrote: >>>> The TX path had been dropped from the Device Memory TCP patch series >>>> post RFCv1 [1], to make that series slightly easier to review. This >>>> series rebases the implementation of the TX path on top of the >>>> net_iov/netmem framework agreed upon and merged. The motivation for >>>> the feature is thoroughly described in the docs & cover letter of the >>>> original proposal, so I don't repeat the lengthy descriptions here, but >>>> they are available in [1]. >>>> >>>> Sending this series as RFC as the winder closure is immenient. I plan on >>>> reposting as non-RFC once the tree re-opens, addressing any feedback >>>> I receive in the meantime. >>> >>> I guess you should drop this paragraph. >>> >>>> Full outline on usage of the TX path is detailed in the documentation >>>> added in the first patch. >>>> >>>> Test example is available via the kselftest included in the series as well. >>>> >>>> The series is relatively small, as the TX path for this feature largely >>>> piggybacks on the existing MSG_ZEROCOPY implementation. >>> >>> It looks like no additional device level support is required. That is >>> IMHO so good up to suspicious level :) >>> >> >> It is correct no additional device level support is required. I don't >> have any local changes to my driver to make this work. I think Stan >> on-list was able to run the TX path (he commented on fixes to the test >> but didn't say it doesn't work :D) and one other person was able to >> run it offlist. > > For BRCM I had shared this: https://lore.kernel.org/netdev/ZxAfWHk3aRWl-F31@mini-arch/ > I have similar internal patch for mlx5 (will share after RX part gets > in). I agree that it seems like gve_unmap_packet needs some work to be more > careful to not unmap NIOVs (if you were testing against gve). What happen if an user try to use devmem TX on a device not really supporting it? Silent data corruption? Don't we need some way for the device to opt-in (or opt-out) and avoid such issues? /P
