I think that if journald hit an error trying to write to the intended log target, it will fallback to writing to kmsg, so this might be intended. Is there anything interesting in journald's own logs?
$ journalctl -u systemd-journald.service -b > journald.log Also please share your journald.conf: $ systemd-analyze cat-config systemd/journald.conf ** Changed in: systemd (Ubuntu) Importance: Undecided => Low ** Changed in: systemd (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/2007792 Title: journald putting rotation messages into dmesg Status in systemd package in Ubuntu: Incomplete Bug description: Getting many messages like this in my dmesg: [207441.489056] systemd-journald[1439]: Data hash table of /run/log/journal/de5de074689f427db9c98ca2ef0070f0/system.journal has a fill level at 75.0 (82165 of 109553 items, 41943040 file size, 510 bytes per hash table item), suggesting rotation. [207441.489064] systemd-journald[1439]: /run/log/journal/de5de074689f427db9c98ca2ef0070f0/system.journal: Journal header limits reached or header out-of-date, rotating. I made sure ForwardToKMsg=no is in /etc/systemd/journald.conf. This is new behavior since updating to lunar... so I think it is a bug? ProblemType: Bug DistroRelease: Ubuntu 23.04 Package: systemd 252.4-1ubuntu1 Uname: Linux 6.2.0-rc8 x86_64 NonfreeKernelModules: zfs ApportVersion: 2.24.0-0ubuntu2 Architecture: amd64 CasperMD5CheckResult: unknown Date: Sun Feb 19 18:21:03 2023 InstallationDate: Installed on 2019-10-19 (1219 days ago) InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017) MachineType: MSI MS-7998 ProcEnviron: TERM=screen.xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash ProcKernelCmdLine: BOOT_IMAGE=/BOOT/ubuntu_aoozig@/vmlinuz-6.2.0-rc8 root=ZFS=rpool/ROOT/ubuntu_aoozig ro drm.edid_firmware=edid/edid.bin mpt3sas.logging_level=1 fsck.mode=force fsck.repair=yes cpuidle.governor=teo swapaccount=1 mitigations=off init_on_alloc=0 loglevel=3 usbcore.autosuspend=-1 SourcePackage: systemd UpgradeStatus: Upgraded to lunar on 2021-02-06 (743 days ago) dmi.bios.date: 06/15/2018 dmi.bios.release: 5.12 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 2.A0 dmi.board.asset.tag: Default string dmi.board.name: C236A WORKSTATION (MS-7998) dmi.board.vendor: MSI dmi.board.version: 1.0 dmi.chassis.asset.tag: Default string dmi.chassis.type: 3 dmi.chassis.vendor: MSI dmi.chassis.version: 1.0 dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2.A0:bd06/15/2018:br5.12:svnMSI:pnMS-7998:pvr1.0:rvnMSI:rnC236AWORKSTATION(MS-7998):rvr1.0:cvnMSI:ct3:cvr1.0:skuDefaultstring: dmi.product.family: Default string dmi.product.name: MS-7998 dmi.product.sku: Default string dmi.product.version: 1.0 dmi.sys.vendor: MSI modified.conffile..etc.default.apport: # set this to 0 to disable apport, or to 1 to enable it # you can temporarily override this with # sudo service apport start force_start=1 enabled=0 mtime.conffile..etc.default.apport: 2020-08-10T16:14:34.416087 mtime.conffile..etc.systemd.journald.conf: 2023-02-14T17:44:33.368969 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/2007792/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp