On Wed, 31 Jan 2024 22:37:50 +0100 Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote: Hi all! > Hello Dan, > > On 31.01.24 22:03, Dan Shelton wrote: > > Hello! > > > > Does barebox support booting from a NFSv4 filesystem, e.g. boot from > > NFSv4 filesystem into a Linux NFSv4 netroot (diskless machine)? > > The barebox network stack only does UDP/IP. There have been attempts to > bring a TCP stack into barebox, but none have so far succeeded to > make it mainline. This is a hard requirement before we can consider > supporting NFSv4. I hope that lwIP could fill this gap in the future, > but no one is actively continuing this work as far as I am aware[1]. > > > We need NFSv4, because it does not need rpcbind, and combines > > filesystem, lockd and other stuff all in one TCP port (2049). Site > > policy also does not allow NFSv2/NFSv3, but allows NFSv4. > > Please note that this only concerns barebox and that kernel nfsroot is > unaffected. You can load kernel and device tree over TFTP and supply a > suitable command line argument to the kernel to use a NFS root. > > The standard net boot target does just that: > https://elixir.bootlin.com/barebox/v2024.01.0/source/defaultenv/defaultenv-2-base/boot/net > > It specifies TCP, but hardcodes v3 currently. I guess we could drop the v3 and let > the kernel decide on its own what version it will use? If that doesn't work, you can > override the file locally in your environment, e.g. via CONFIG_DEFAULT_ENVIRONMENT > pointing at a directory that contains a boot/net file with the appropriate > changes (or just call your boot target something else like boot/nfsv4). > > Hope this helps. > > [1]: Some attempts I am aware of: > https://github.com/a3f/barebox/tree/lwip It looks like lwip is BSD-3-clause-licensed. Can we use the BSD-3-clause code in barebox? > https://github.com/olerem/barebox/tree/picotcp-2019.06.29 > https://github.com/jmaselbas/barebox/commit/4a987bfdc2ad50c13126dd6290d2477c3fc0c87d -- Best regards, Antony Pavlov
