[PATCH v2 0/3] Switch from mdevd to systemd-udevd in root filesystem

[Demi Marie Obenour <demiobenour@gmail.com>]

systemd-udevd provides support for significantly more hardware than
mdevd does.  Therefore, switch to it.

All of the non-Nix code has been tested.  However, this was done using
an alternate default.nix (see v1) that used glibc.  NixOS's binary cache
doesn't include many packages built with musl, and Spectrum OS's binary
cache doesn't include packages built with systemd's libudev, so a huge
number of packages need to be built from source.  This still has not
finished.

Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
---
Changes in v2:
- Use more optional arguments instead of positional parameters in
  sd-notify-wrapper.
- Explain why explicit modprobe is needed.
- Link to v1: https://spectrum-os.org/lists/archives/spectrum-devel/20250913-udev-v1-0-eade4ab8f2b4@gmail.com

---
Demi Marie Obenour (3):
      tools: Add adapter tool for services using sd_notify
      host/rootfs: Switch to systemd-udevd
      host/rootfs: Simplify s6-rc dependencies

 host/rootfs/Makefile                               |  35 ++--
 host/rootfs/default.nix                            | 112 ++++-------
 host/rootfs/image/etc/mdev.conf                    |   7 -
 host/rootfs/image/etc/mdev/listen                  |  11 --
 host/rootfs/image/etc/mdev/wait                    |  14 --
 host/rootfs/image/etc/s6-rc/basic/contents         |  18 ++
 .../rootfs/image/etc/s6-rc/{vmm-env => basic}/type |   0
 .../etc/s6-rc/{vmm-env => basic}/type.license      |   0
 host/rootfs/image/etc/s6-rc/card0/type.license     |   2 -
 host/rootfs/image/etc/s6-rc/card0/up               |   4 -
 host/rootfs/image/etc/s6-rc/kvm/up                 |   5 +-
 host/rootfs/image/etc/s6-rc/mdevd-coldplug/type    |   1 -
 host/rootfs/image/etc/s6-rc/mdevd-coldplug/up      |   4 -
 .../image/etc/s6-rc/mdevd/notification-fd.license  |   2 -
 host/rootfs/image/etc/s6-rc/mdevd/run              |   5 -
 host/rootfs/image/etc/s6-rc/ok-all/contents        |  19 +-
 .../mdevd => sys-vmms/dependencies.d/vm-env}       |   0
 .../dependencies.d/systemd-udevd}                  |   0
 .../s6-rc/{card0 => systemd-udevd-coldplug}/type   |   0
 .../type.license                                   |   0
 .../image/etc/s6-rc/systemd-udevd-coldplug/up      |   3 +
 .../card0 => systemd-udevd/flag-essential}         |   0
 .../s6-rc/{mdevd => systemd-udevd}/notification-fd |   0
 .../s6-rc/systemd-udevd/notification-fd.license    |   2 +
 host/rootfs/image/etc/s6-rc/systemd-udevd/run      |  14 ++
 .../image/etc/s6-rc/{mdevd => systemd-udevd}/type  |   0
 .../s6-rc/{mdevd => systemd-udevd}/type.license    |   0
 host/rootfs/image/etc/s6-rc/vm-env/contents        |  12 +-
 host/rootfs/image/etc/s6-rc/vm-env/type.license    |   2 -
 host/rootfs/image/etc/s6-rc/vmm-env/contents       |   6 -
 .../image/etc/s6-rc/weston/dependencies.d/basic    |   0
 .../image/etc/udev/rules.d/99-spectrum.rules       |   9 +
 host/rootfs/image/usr/bin/vm-start                 |   2 +-
 .../{etc/mdev/net/add => usr/libexec/net-add}      |   0
 tools/default.nix                                  |   1 +
 tools/meson.build                                  |   1 +
 tools/sd-notify-adapter/meson.build                |   4 +
 tools/sd-notify-adapter/sd-notify-adapter.c        | 206 +++++++++++++++++++++
 38 files changed, 342 insertions(+), 159 deletions(-)
---
base-commit: 0fcf508e884944a2875fb52dbf58a977aa5df6e8
change-id: 20250911-udev-24cf4bf68fbe
-- 
Sincerely,
Demi Marie Obenour (she/her/hers)