Re: Soft scrolling on framebuffer consoles - with GPM Handling - revised for kernel 6.18.28 (etc.)

Hello, Vitaly.

On Wed, May 13, 2026 at 00:24:57 +0400, Vitaly Zdanevich wrote:
>    Thanks.

Thank you for trying it out!

>    Â

>    Can it [patch to enable soft scrolling in the gentoo-sources kernel]
>    be integrated into gentoo-sources? Or with USE flag?

This would be difficult.  The patch is highly unofficial, and has not
received any formal testing.  There have definitely been bugs in earlier
versions of it, and it would be foolish to assert the current version is
bug free.

To be integrated into gentoo-sources, its maintainer would need
persuading that the code is (?relatively) free of bugs.  But this would
make gentoo-sources significantly different from the upstream kernel,
with all the hassle that would entail.

The best way of integrating the patch would be for it to be accepted by
the upstream kernel maintainers.  I don't see this as likely.  These
maintainers are (by necessity) highly conservative, and the process for
getting new code accepted into Linux is rigorous in the extreme.

Besides, the decision some years ago to remove soft scrolling from the
kernel was taken by Linus Torvalds personally, on account of some
security problem associated with it.  I've not been able to find a
description of this bug, or a test case for it, but I did read a rumour
that it was something to do with changing the screen dimensions (e.g. by
loading a different sized font) when there was an existing scrolling
buffer.  Or something like that.  So I would expect significant political
problems here, too.

So, while I would like the patch to be incorporated into gentoo-sources,
I can't see it as likely to happen.

-- 
Alan Mackenzie (Nuremberg, Germany).