On 5/12/25 6:49 PM, Jason Xing wrote: > On Mon, May 12, 2025 at 10:55?PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: >> >> On Mon, May 12, 2025 at 09:14:56AM +0300, Andy Shevchenko wrote: >>> Also note, we usually do not care about the out-of-tree users. The main Q here >>> why are they out-of-tree for so long time? >> >> We do not care. If some of this ever gets submitted it can add the >> needed helpers back. >> >> This entire discussion is silly. >> > > I'm surprised how you described it.... > > Now relay works like a filesystem which helps out-of-tree users > transfer a large amount of data efficiently. it's totally not like > other pure dead code. I meant what the trouble of just leaving it > untouched in the kernel could be? > > Let me put in a simpler way, two options, 1) just clean up, 2) keep it > and help so-called 'out-of-tree' users even if you don't care. I don't > figure out what the difficulty of keeping it is :S I think Christoph's email was quite clear, and I also said _exactly_ the same thing in an email two days ago: we never EVER keep code in kernel that isn't used by in-kernel code. Period. It's not a debate, this is the law, if you will. It's a core principle because it allows the kernel to be maintainable, rather than need to care about out of tree code when changes are made. Similarly, we don't have a kernel API, not even at the source level. This is one of the core tenets of the Linux kernel, and all in-tree code must follow those. If you have aspirations of maintaining the relay code going forward, you need to fully understand that. Either the dead code goes, or the out-of-tree code that uses it must be merged. There's no in-between. -- Jens Axboe
