Re: [PATCH 0/3] vmsplice: make vmsplice a trivial wrapper for preadv2/pwritev2

[Askar Safin]

Andy Lutomirski <luto@xxxxxxxxxxxxxx>:
> On Wed, Jun 3, 2026 at 3:43 PM Askar Safin <safinaskar@xxxxxxxxx> wrote:
> > Finally, we can degrade tee(2) to copy, and hopefully this will
> > allow us to always be sure that pipe buffers are not shared with anything.
> > This is possible future direction.
> 
> I'm a bit nervous that, if I've read the code correctly (a big if),
> then iscsi and nvme will still send *shared* buffers via
> MSG_SPLICE_PAGES, but that normal user code will not be able to do
> this, and that something will bitrot.

As well as I understand you correctly, you mean that if we remove
tee(2), then there still will be subsystems, which will be able to
send shared pages.

Yes, I totally agree.

So, if we remove tee(2), then we will probably need to remove all
non-standard implementations of pipe_buf_operations.

-- 
Askar Safin