[PATCH V2 0/6][SRU][OEM-5.14/Jammy/OEM-5.17/Unstable] build backport-iwlwifi-dkms as linux-modules-iwlwifi-ABI

[You-Sheng Yang]

From: "You-Sheng Yang (vicamo)" <vicamo.yang at canonical.com>

BugLink: https://bugs.launchpad.net/bugs/1969434

[Impact]

Intel AX211 iwlwifi -64 firmware may fail to init under reboot stress,
and -67 is immune. FW API -64 supported by oem-5.14, and -67 in v5.16.
Not reproducible on every platform with AX211 installed, and the chances
of such failures vary from one to another.

[Fix]

A few solutions were considered. The very first one is to ask Intel to
fix -64 firmware directly, and the answer is a solid no claimed -64 is
not the planned production version of AX211.

It's also possible to backport FW API from v5.16, but while iwlwifi FW
API is more or less a black box to us and the new FW APIs also depends
on updates on the wireless stack, this is going to be very risky and
actually we had regressions before after such backports.

The last viable solution is to run backport-iwlwifi-dkms >= rev 8580 on
the effected platforms. This means oem-5.14 and its migration target,
hwe-5.15 will not be able to drive this piece of hw flawlessly without
backport-iwlwifi-dkms installed.

However, while we need secureboot to be enabled on these platforms,
backport-iwlwifi-dkms must also be signed somehow. There are two
possible method to achieve this, too. One, to prebuild this dkms as zfs
and v4l2loopback does. However, while backport-iwlwifi-dkms generates
kernel modules with exactly the same name as the in-tree ones, when
prebuilt, they'll be available directly from the linux-modules package
and therefore overrides the in-tree ones always, turning the in-tree
driver completely useless and risk the stability of all other generic
installations.

The second one is to build backport-iwlwifi-dkms as nvidia graphic
drivers in the linux-restricted-modules source package. In this way,
affected platforms may install the corresponding packages when needed
without interfering others. However, l-r-m is for restricted modules
that needs special care of redistribution of its binaries, and
backport-iwlwifi-dkms is GPL licensed.

Here a similar but simpler process in the main kernel tree is
re-implemented. Two additional packages,
linux-modules-MODULE-PKGVER-ABINUM-FLAVOUR and its meta package
linux-modules-MODULE-FLAVOUR will be created.

[Test Case]

Test builds:
./jammy/amd64/linux-modules-iwlwifi-5.15.0-27-generic_5.15.0-27.28_amd64.deb
./jammy/amd64/linux-modules-iwlwifi-generic_5.15.0-27.28_amd64.deb
./unstable/amd64/linux-modules-iwlwifi-5.17.0-8-generic_5.17.0-8.8_amd64.deb
./unstable/amd64/linux-modules-iwlwifi-generic_5.17.0-8.8_amd64.deb
./oem-5.17/amd64/linux-modules-iwlwifi-5.17.0-1003-oem_5.17.0-1003.3_amd64.deb
./oem-5.17/amd64/linux-modules-iwlwifi-oem_5.17.0-1003.3_amd64.deb
./oem-5.14/amd64/linux-modules-iwlwifi-5.14.0-1033-oem_5.14.0-1033.36_amd64.deb
./oem-5.14/amd64/linux-modules-iwlwifi-oem_5.14.0-1033.36_amd64.deb

[Where problems could occur]

Different from nvidia packages built from l-r-m, the generated package
names do not carry an additional short version string, e.g. nvidia-410,
as there is no such necessity to build multiple versions of iwlwifi.
The modules are installed to /lib/modules/<kver>/kernel/iwlwifi, not
iwlwifi-9858/.

V2:
* extend debian/dkms-versions to carry all the module specific
  parameters. Also rewrite debian/scripts/control-create a bit to lookup
  module name automatically.
* add arch=foo in debian/dkms-versions. This also removes do_<module>
  settings in $DEBIAN/rules.d/<arch>.mk. Their initial values will be
  assigned automatically if not already specified.
* add rprovides=foo in debian/dkms-versions.
* support dkms_include and dkms_exclude settings. When enlisted, a
  specified module will become available to the current arch if not
  explicitly excluded again in dkms_exclude.
* rewrite those do_<module>_disable as well.
* indentation and white spaces.
* fix build failure when multiple standalone modules are involved.
* bump backport-iwlwifi-dkms version.
* remove do_standalone_dkms from V1 as we don't need it.

You-Sheng Yang (vicamo) (6):
  UBUNTU: [Packaging] refactor dkms-versions to carry modulename
  UBUNTU: [Packaging] add debpath= in dkms-versions
  UBUNTU: [Packaging] add rprovides= in dkms-versions
  UBUNTU: [Packaging] add arch= in dkms-versions
  UBUNTU: [Packaging] support build dkms as standalone package
  UBUNTU: [Packaging] support building backport-iwlwifi-dkms as
    standalone modules

 debian.master/rules.d/amd64.mk       |  2 --
 debian.master/rules.d/arm64.mk       |  1 -
 debian.master/rules.d/ppc64el.mk     |  1 -
 debian.master/rules.d/s390x.mk       |  2 --
 debian/control.d/flavour-module.stub | 30 ++++++++++++++++++++
 debian/dkms-versions                 |  5 ++--
 debian/rules                         | 25 ++++++++---------
 debian/rules.d/0-common-vars.mk      | 36 ++++++++++++++++++++++++
 debian/rules.d/2-binary-arch.mk      | 42 ++++++++++++++++++++++------
 debian/scripts/control-create        | 28 +++++++++++++++++++
 10 files changed, 143 insertions(+), 29 deletions(-)
 create mode 100644 debian/control.d/flavour-module.stub

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2.34.1