[PATCH v4 0/2][SRU][linux-meta][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 (in linux-meta) will be created.

[Test Case]

Test builds:

linux$ ls */*/*iwlwifi*
jammy/amd64/linux-modules-iwlwifi-5.15.0-2029-generic_5.15.0-2029.30+lp1969434.3_amd64.deb
oem-5.14/amd64/linux-modules-iwlwifi-5.14.0-2035-oem_5.14.0-2035.38+lp1969434.3_amd64.deb
oem-5.17/amd64/linux-modules-iwlwifi-5.17.0-2004-oem_5.17.0-2004.4+lp1969434.3_amd64.deb
unstable/amd64/linux-modules-iwlwifi-5.18.0-2002-generic_5.18.0-2002.2+lp1969434.3_amd64.deb

meta$ ls */*iwlwifi*
jammy/linux-modules-iwlwifi-generic_5.15.0.29.32+lp1969434.3_amd64.deb
jammy/linux-modules-iwlwifi-generic-hwe-22.04_5.15.0.29.32+lp1969434.3_amd64.deb
jammy/linux-modules-iwlwifi-generic-hwe-22.04-edge_5.15.0.29.32+lp1969434.3_amd64.deb
jammy/linux-modules-iwlwifi-virtual_5.15.0.29.32+lp1969434.3_amd64.deb
jammy/linux-modules-iwlwifi-virtual-hwe-22.04_5.15.0.29.32+lp1969434.3_amd64.deb
jammy/linux-modules-iwlwifi-virtual-hwe-22.04-edge_5.15.0.29.32+lp1969434.3_amd64.deb
oem-5.14/linux-modules-iwlwifi-oem-20.04_5.14.0.1035.32+lp1969434.3_amd64.deb
oem-5.14/linux-modules-iwlwifi-oem-20.04d_5.14.0.1035.32+lp1969434.3_amd64.deb
oem-5.17/linux-modules-iwlwifi-oem-22.04_5.17.0.1004.4+lp1969434.3_amd64.deb
oem-5.17/linux-modules-iwlwifi-oem-22.04a_5.17.0.1004.4+lp1969434.3_amd64.deb
unstable/linux-modules-iwlwifi-generic-wip_5.18.0.2.10+lp1969434.3_amd64.deb
unstable/linux-modules-iwlwifi-virtual-wip_5.18.0.2.10+lp1969434.3_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>/ubuntu/iwlwifi, not
iwlwifi-9858/.

V4:
* support multiple debpath parameters
* fix depending package version in meta packages

V3:
* move meta pacakge generation to linux-meta, and update kernel-versions
  according to the versions required.
* allow %package%, %version%, %module% in debpath parameter, so that no
  additional work introduced in kernel-versions update-dkms-versions
  script. Also handle version epoch.
* bump versions for unstable only due to build breaks against v5.18-rcX.
* fix dkms_exclude/dkms_include.
* introduction type= parameter with currently 2 possible values,
  standalone and built-in (default).
* use "any" instead of "__all__" for unspecified module architecture.
* introduce dkms_foo_subdir that is used to install built-in modules in
  kernel/ and standalone ones in ubuntu/.
* and since dkms-versions of oem-5.14 is tracking that of impish,
  dkms-versions/impish:main is updated with additional parameters.

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) (2):
  UBUNTU: [Packaging] support standalone dkms module builds
  UBUNTU: [Packaging] resync debian/dkms-versions from main package

 debian/control.d/generic |  2 +-
 debian/control.dkms      | 10 ++++++
 debian/dkms-versions     |  5 +--
 debian/rules             | 69 +++++++++++++++++++++++++++++++++++++---
 4 files changed, 78 insertions(+), 8 deletions(-)
 create mode 100644 debian/control.dkms

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2.34.1