Hello, Gentoo.

On Fri, Feb 03, 2023 at 18:56:27 +0000, Alan Mackenzie wrote:

The topic of this post is my kernel patch which enables soft scrolling
on Linux tty's with <shift><PgUp> and <shift><PgDn>, and also enables
the GPM mouse utility on those scrolled regions.

Currently, the patch I posted some months ago works on all 6.1.x
kernels, and very likely works on 6.2.x, too.  In kernel 6.3.1, some
significant refactoring was done by the kernel people, necessitating a
new version of the patch, called 6.3.11-GPM.20231004.diff.  I've tested
this on 6.3.11 and 6.5.5.

Just a quick reminder of how to use these files for anybody else who
might be interested:
(i) cd /usr/src/linux-6.3.11-gentoo, or similar.  (Or ...-6.1.x-gentoo).
(ii) patch -p1 < 6.3.11-GPM.20231004.diff (or the other one).
(iii) Configure the kernel as normal.  Additionally, under Device
drivers/Graphic Support/Console display driver support, enable
CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK, set the buffer size to taste
(it's default is 128 kB) and accept the default enablement of
CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_GPM.
(iv) Build the kernel and install it into your boot manager.
(v) Reboot and enjoy!  You can now use GPM in scrolled consoles.

Just a warning: if you copy your kernel .config from a 6.1.x kernel, and
use make oldconfig to generate a new kernel for 6.3.x etc., you will
have to enable CONFIG_HID_SUPPORT, otherwise your USB keyboard and mouse
will be dead on bootup.  ;-(

The usual disclaimers apply, here.  If this patch breaks anything for
you, you get to join the pieces back together again.  But if this does
happen, please let me know, so that I can try to fix the bug.  My only
promise is that there's nothing malicious in the patch.

As well as 6.3.11-GPM.20231004.diff, I'm reposting
6.1.8-GPM.20230203.diff for anybody new here who wants to try it on the
current Gentoo 6.1.x kernel.

-- 
Alan Mackenzie (Nuremberg, Germany).