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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , Alex Shi , Yanteng Si , Dongliang Mu , Michael Chan , Pavan Chebbi , Joshua Washington , Harshitha Ramamurthy , Saeed Mahameed , Tariq Toukan , Mark Bloch , Leon Romanovsky , Alexander Duyck , kernel-team@meta.com, Nikolay Aleksandrov , Shuah Khan , David Wei , netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, Stanislav Fomichev , Mina Almasry , Bobby Eshleman Subject: Re: [PATCH net-next 00/11] net: devmem: support devmem with netkit devices Message-ID: References: <20260428-tcp-dm-netkit-v1-0-719280eba4d2@meta.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Apr 29, 2026 at 02:08:31PM +0200, Daniel Borkmann wrote: > Hi Bobby, > > On 4/29/26 12:41 AM, Bobby Eshleman wrote: > > This series enables TCP devmem TX through netkit devices. > > > > Netkit now supports queue leasing. A physical NIC's RX queue can be > > leased to a netkit guest interface inside a container namespace. This > > gives the container a devmem-capable data path on the RX side (bind-rx, > > etc...). On the TX side, the container process binds to its netkit guest > > interface and sends traffic that netkit redirects (via BPF or ip > > forwarding) to the physical NIC for DMA. > [...] > Thanks for working on this, after the RX queue leasing got merged, I've > been looking into the same actually. :) > > I think the NETMEM_TX_* enum approach seems reasonable. > > What I have a PoC on is to build out TX queue leasing as first-class > symmetric infrastructure to complement the RX queue leasing - basically > I implemented an equivalent to the latter in netdev_nl_queue_create_doit > et al, so you can have independent RX and TX leases and per-queue > accountability, such that ynl queue-get op shows the full picture, and > lastly we could also enable AF_XDP TX-only support through this infra. > > Would you be open to collab on integrating both and migrating the devmem > code to work off an TX queue object? Next week is LSF/MM/BPF, are you > there by any chance to catch up in person? > Hey Daniel, Definitely am open to that. I will unfortunately not be at LSF/MM/BPF, but maybe we can schedule a meeting offline to sync up? On the approach, explicit TX queue leasing sounds like a better way to permit devmem's tx binding than implicitly via RX lease. Best, Bobby