#1110780 linux-image-6.12.38+deb13-amd64: HID BPF support is not enabled by default

Package:
src:linux
Source:
src:linux
Submitter:
Raghavendra Kamath
Date:
2025-08-23 08:45:01 UTC
Severity:
normal
Tags:
#1110780#5
Date:
2025-08-11 07:03:21 UTC
From:
To:
Dear Maintainer,

   * What led up to the situation?
	I am an artist using digital graphic tablet and I need a program
	called udev-hid-bpf to configure my tablet pen. To use this tool
	there needs to be HID-BPF support enabled in the kernel. This is
	missing in the default kernel. I would have to use liquorix or
	some other kernel but those give other issues such as wifi not
	working etc.
	So I request you to please enable support for HID-BPF support
	in the kernel.
	Many artists who are using linux will need this support enabled.
	You can read more about this on the blog post from David Revoy
	here - https://www.davidrevoy.com/article1053/xppen-artist-pro-19-gen-2-review-on-gnulinux#fix-unwanted-eraser-mode-on-stylus

   * What exactly did you do (or not do) that was effective (or
     ineffective)?
     I tried to report this issue to the udev-hid-bpf developers and
     they were the ones who told me that debian doesn't have this
     support. You can read the bug report here - https://gitlab.freedesktop.org/libevdev/udev-hid-bpf/-/issues/70#note_3046884

   * What outcome did you expect instead?
	HID-BPF support to be enabled by default in the kernel
#1110780#10
Date:
2025-08-14 13:39:15 UTC
From:
To:
I confirm this, and I also wish Debian's default kernel lines had HID-BPF support (and also an up to date https://gitlab.freedesktop.org/libevdev/udev-hid-bpf/ *.deb packaged, but that's another story).

It's a must have for getting a better hardware support for many HID hardware (not only graphic tablet).
#1110780#17
Date:
2025-08-18 05:58:55 UTC
From:
To:
Hi,

It might make only sense really if we have as ewll udev-hid-bpf . But
as this is like a chicken-egg problem, I'm proposing to enable HID_BPF
alrady on kernel config side, I will see if there are objections from
the other team members.

Cf. https://salsa.debian.org/kernel-team/linux/-/merge_requests/1614

Regards,
Salvatore
#1110780#22
Date:
2025-08-18 07:25:20 UTC
From:
To:
Hi Salvatore
Thank you so much for proposing this change. I hope it goes through the
review.
Will this be in backports or the next update for trixie or in testing?
Sorry I am not that well accustomed to how Debian bug fix release works.

Thank you once again for listening to us.
#1110780#27
Date:
2025-08-18 09:04:43 UTC
From:
To:
Hi Raghavendra,

The plan is as follows: Once it is merged, the version will go at some
point into Debian unstable and testing. Once it is in testing there
will eventually be a trixie-backports version including it.

Not yet made our mind up if the change can be as well enabled in
trixie with its default kernel. Technically it is not, since it is a
new feature, so out of scope. Adding hardware support is. But it's
different here there is no udev-hid-bpf at all packages.

So we would need to live with it and have to use the backports version
for cases where needed.

But let's first in any case see if we land it in 6.16.y based version.

Regards,
Salvatore