Fails to build against linux-5.15 after stable update

[Manuel Diewald]

[ Impact ]

Upstream stable update v5.15.170 [1] for jammy introduces a backport of upstream commit [2]

56440d7ec28d genetlink: hold RCU in genlmsg_mcast()

which drops the @flags parameter from function genlmsg_multicast_allns(). The backport-iwlwifi module does not use its compat implementation of that function when building against 5.15 but links against what the kernel is providing. The build will consequently fail with:

<<DKMSDIR>>/build/backport-iwlwifi/11510/build/net/wireless/nl80211.c: In function 'nl80211_common_reg_change_event':
<<DKMSDIR>>/build/backport-iwlwifi/11510/build/net/wireless/nl80211.c:17769:9: error: too many arguments to function 'genlmsg_multicast_allns'
17769 | genlmsg_multicast_allns(&nl80211_fam, msg, 0,
      | ^~~~~~~~~~~~~~~~~~~~~~~
In file included from <<DKMSDIR>>/build/backport-iwlwifi/11510/build/backport-include/net/genetlink.h:3,
                 from <<DKMSDIR>>/build/backport-iwlwifi/11510/build/net/wireless/nl80211.c:25:
./include/net/genetlink.h:342:5: note: declared here
  342 | int genlmsg_multicast_allns(const struct genl_family *family,
      | ^~~~~~~~~~~~~~~~~~~~~~~

In order to build against the kernel with the modified function signature of genlmsg_multicast_allns() we need to patch net/wireless/nl80211.c that is shipped with backport-iwlwifi and drop the now superfluous @flag parameter.

[ Test Plan ]

This issue can be reproduced by trying to build the dkms package against a 5.15 kernel, e.g. jammy linux, with stable update v5.15.170 applied.

[ Where problems could occur ]

If at some point the compat implementation of the affected functionality were to be used instead of what the kernel provides, the mismatch between the calls in net/wireless/nl80211.c and the compat version of genlmsg_multicast_allns() would cause the build to break again.

[ Other Info ]

[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2089272
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=56440d7ec28d60f8da3bfa09062b3368ff9b16db

[You-Sheng Yang (vicamo)]

This has been covered by bug 2083994, FTBFS against v6.12. However, bug 2083994 covers several more API changes and this is only one of them. This, commit 56440d7ec28d, has been backported to multiple stable kernels:
* v5.4.285 (linux/focal, no linux-modules-iwlwifi)
* v5.10.229
* v5.15.170 (linux/jammy, has linux-modules-iwlwifi)
* v6.1.115
* v6.6.59 (will affect linux-6.8/noble later, has linux-modules-iwlwifi)
* v6.11.6 (linux/oracular, has linux-modules-iwlwifi)

[Manuel Diewald (diewald)]

You're right, I didn't notice the changes for #2083994 also include a fix to address this issue. I think to make things less confusing I'll mark this bug as duplicate and close my merge request.

[Stefan Bader (smb)]

I am removing the duplicate for the following reason: this driver is used for compiling as part of the kernel build. So the same version used in Jammy will be used for focal:linux-hwe-5.15. But for jammy:linux-hwe-6.8 (which is the last hwe kernel in Jammy) we will use the driver from Noble.

So we can go ahead just concentrating on 5.15 and work on updates for later kernel in the newer series.

[Stefan Bader (smb)]

I would propose to use the attached approach here. Tested compilation with the current 5.15 kernel. I still have to do a test compile against the upcoming kernel.

[You-Sheng Yang (vicamo)]

Attach debdiff for backport-iwlwifi-dkms/oracular. Prebuilt binaries
will be in https://launchpad.net/~vicamo/+archive/ubuntu/sru

[You-Sheng Yang (vicamo)]

While noble-6.8 is not an upstream LTS release, it's receiving stable fixes from linux-6.10.y and linux-6.6.y. The genlmsg_mcast commit was backported to v6.6.59, and we have v6.6.55 & v6.10.14 in noble/master-next at this moment. While there is no way to identify the kernel version to fix at this case, this is going to take a dkms build time configure script to resolve this problem.

[Stefan Bader (smb)]

So I have finished test-compiling against the next kernel version as well with the proposed iwlwifi driver package:

ubuntu@testj1:~$ dpkg -l|grep iwlwifi
ii backport-iwlwifi-dkms 11510-0ubuntu1~22.04.2 all iwlwifi driver backport in DKMS format
ubuntu@testj1:~$ dkms status
backport-iwlwifi/11510, 5.15.0-130-generic, x86_64: installed
backport-iwlwifi/11510, 5.15.0-132-generic, x86_64: installed
ubuntu@testj1:~$ uname -a
Linux testj1 5.15.0-132-generic #142 SMP Tue Jan 14 21:15:30 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux

If nothing else speaks against it, we might go ahead with sponsoring that?

[You-Sheng Yang (vicamo)]

Attach debdiff for backport-iwlwifi-dkms/jammy.

This backports the patch used in backport-iwlwifi-dkms/plucky.
backport-iwlwifi has a compact layer that adapts the latest kernel
interface to the one being compiled against. The driver source files
should use the new kernel API interface as possible, and sources under
backport-include/ and compat/ redirect/reimplement the call
appropriately.

[Timo Aaltonen (tjaalton)]

Hello Manuel, or anyone else affected,

Accepted backport-iwlwifi-dkms into jammy-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/backport-iwlwifi-dkms/11510-0ubuntu1~22.04.2 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-jammy to verification-done-jammy. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-jammy. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Timo Aaltonen (tjaalton)]

Hello Manuel, or anyone else affected,

Accepted backport-iwlwifi-dkms into oracular-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/backport-iwlwifi-dkms/1:0~89.12325-git36c5be1a-0ubuntu2 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-oracular to verification-done-oracular. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-oracular. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[You-Sheng Yang (vicamo)]

Following comment #7, to add such configure mechanism in bug 2095138.

[You-Sheng Yang (vicamo)]

Verified:
* backport-iwlwifi-dkms/oracular-proposed version 1:0~89.12325-git36c5be1a-0ubuntu2 with:
  - 6.11.0-8-generic
  - 6.11.0-9-generic
  - 6.11.0-12-generic
  - 6.11.0-13-generic
  - 6.11.0-14-generic
  - 6.11.0-17-generic (covers v6.11.6 and therefore genlmsg_multicast_allns API change)
  - 6.11.0-18-generic
  - 6.11.0-20-generic

[You-Sheng Yang (vicamo)]

Verified:
* backport-iwlwifi-dkms/jammy-proposed version 11510-0ubuntu1~22.04.2 with:
  -5.15.0-93-generic
  -5.15.0-94-generic
  -5.15.0-97-generic
  -5.15.0-100-generic
  -5.15.0-101-generic
  -5.15.0-102-generic
  -5.15.0-104-generic
  -5.15.0-105-generic
  -5.15.0-106-generic
  -5.15.0-107-generic
  -5.15.0-111-generic
  -5.15.0-112-generic
  -5.15.0-113-generic
  -5.15.0-115-generic
  -5.15.0-116-generic
  -5.15.0-117-generic
  -5.15.0-118-generic
  -5.15.0-119-generic
  -5.15.0-120-generic
  -5.15.0-121-generic
  -5.15.0-122-generic
  -5.15.0-124-generic
  -5.15.0-125-generic
  -5.15.0-126-generic
  -5.15.0-127-generic
  -5.15.0-128-generic
  -5.15.0-130-generic
  -5.15.0-131-generic
  -5.15.0-132-generic (covers v5.15.170 and therefore genlmsg_multicast_allns API change)
  -5.15.0-133-generic
  -5.15.0-135-generic
  -5.17.0-15-generic
  -5.17.0-1003-oem
  -5.17.0-1031-oem
  -5.17.0-1032-oem
  -5.17.0-1033-oem
  -5.17.0-1034-oem
  -5.17.0-1035-oem
  -5.19.0-41-generic
  -5.19.0-42-generic
  -5.19.0-43-generic
  -5.19.0-45-generic
  -5.19.0-46-generic
  -5.19.0-50-generic
  -6.0.0-1016-oem
  -6.0.0-1017-oem
  -6.0.0-1018-oem
  -6.0.0-1019-oem
  -6.0.0-1020-oem
  -6.0.0-1021-oem
  -6.1.0-1012-oem
  -6.1.0-1013-oem
  -6.1.0-1014-oem
  -6.1.0-1015-oem
  -6.1.0-1016-oem
  -6.1.0-1017-oem
  -6.1.0-1018-oem
  -6.1.0-1019-oem
  -6.1.0-1020-oem
  -6.1.0-1021-oem
  -6.1.0-1022-oem
  -6.1.0-1023-oem
  -6.1.0-1024-oem
  -6.1.0-1025-oem
  -6.1.0-1026-oem
  -6.1.0-1027-oem
  -6.1.0-1028-oem
  -6.1.0-1029-oem
  -6.1.0-1032-oem
  -6.1.0-1033-oem
  -6.1.0-1034-oem
  -6.1.0-1035-oem
  -6.2.0-23-generic
  -6.2.0-25-generic
  -6.2.0-26-generic
  -6.2.0-31-generic
  -6.2.0-32-generic
  -6.2.0-33-generic
  -6.2.0-34-generic
  -6.2.0-35-generic
  -6.2.0-36-generic
  -6.2.0-37-generic
  -6.2.0-39-generic
  -6.5.0-14-generic
  -6.5.0-15-generic
  -6.5.0-17-generic
  -6.5.0-18-generic
  -6.5.0-21-generic
  -6.5.0-25-generic
  -6.5.0-26-generic
  -6.5.0-27-generic
  -6.5.0-28-generic
  -6.5.0-35-generic
  -6.5.0-41-generic
  -6.5.0-44-generic
  -6.5.0-45-generic
  -6.5.0-1002-oem
  -6.5.0-1003-oem
  -6.5.0-1004-oem
  -6.5.0-1005-oem
  -6.5.0-1006-oem
  -6.5.0-1007-oem
  -6.5.0-1008-oem
  -6.5.0-1009-oem
  -6.5.0-1010-oem
  -6.5.0-1011-oem
  -6.5.0-1013-oem
  -6.5.0-1014-oem
  -6.5.0-1015-oem
  -6.5.0-1016-oem
  -6.5.0-1018-oem
  -6.5.0-1019-oem
  -6.5.0-1020-oem
  -6.5.0-1021-oem
  -6.5.0-1022-oem
  -6.5.0-1023-oem
  -6.5.0-1024-oem
  -6.5.0-1025-oem
  -6.5.0-1027-oem
  -6.8.0-32-generic
  -6.8.0-38-generic
  -6.8.0-39-generic
  -6.8.0-40-generic
  -6.8.0-45-generic
  -6.8.0-47-generic
  -6.8.0-48-generic
  -6.8.0-49-generic
  -6.8.0-50-generic
  -6.8.0-51-generic
  -6.8.0-52-generic
  -6.8.0-53-generic
  -6.8.0-54-generic

[You-Sheng Yang (vicamo)]

Porting to noble to resolve same issue in generic-6.8. This time it also depends on bug 2095138 to detect such API change.

[Launchpad Janitor (janitor)]

This bug was fixed in the package backport-iwlwifi-dkms - 1:0~89.12325-git36c5be1a-0ubuntu2

---------------
backport-iwlwifi-dkms (1:0~89.12325-git36c5be1a-0ubuntu2) oracular; urgency=low

  [You-Sheng Yang]
  * Fails to build against linux-5.15 after stable update (LP: #2089385)
    - backports: genetlink: hold RCU in genlmsg_mcast()

 -- You-Sheng Yang <email address hidden> Wed, 09 Oct 2024 17:13:38 +0800

[Andreas Hasenack (ahasenack)]

The verification of the Stable Release Update for backport-iwlwifi-dkms has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[You-Sheng Yang (vicamo)]

verified backport-iwlwifi-dkms/jammy-proposed version 11510-0ubuntu1~22.04.2 with prebuilt linux-headers from https://launchpad.net/~vicamo/+archive/ubuntu/ppa-2089385 that with mainline kernel commit 56440d7ec28d ("genetlink: hold RCU in genlmsg_mcast()") cherry-picked. Also verified all oem/generic kernels >= 6.2 in Jammy. More complete coverage is being SRU-ed in bug 2095138.

[You-Sheng Yang (vicamo)]

backport-iwlwifi-dkms/noble is being SRU-ed along with bug 2095138. See debdiffs in https://bugs.launchpad.net/ubuntu/+source/backport-iwlwifi-dkms/+bug/2095138/comments/10.

[Timo Aaltonen (tjaalton)]

Hello Manuel, or anyone else affected,

Accepted backport-iwlwifi-dkms into noble-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/backport-iwlwifi-dkms/11510-0ubuntu1.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-noble to verification-done-noble. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-noble. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Timo Aaltonen (tjaalton)]

Hello Manuel, or anyone else affected,

Accepted backport-iwlwifi-dkms into jammy-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/backport-iwlwifi-dkms/11510-0ubuntu1~22.04.3 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-jammy to verification-done-jammy. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-jammy. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[You-Sheng Yang (vicamo)]

Verified backport-iwlwifi-dkms/noble-proposed version 11510-0ubuntu1.1.

[You-Sheng Yang (vicamo)]

verified backport-iwlwifi-dkms/jammy-proposed version 11510-0ubuntu1~22.04.3 against all oem/generic kernels.