Hello everyone, I have been following this thread for a while now, but have not yet seen others report the same thing I am experiencing. I am using an LG Gram 14Z90Q-G.AA76B and have experienced high CPU usage from kworker threads on every distro I have tried (Fedora, ArchLinux, VanillaOS, Ubuntu). >From my experience, there is a somewhat reliable way to temporarily stop the high CPU usage. I don't dualboot windows, so I cannot test the suggestion of booting from windows to linux. Rather, I have noticed the following pattern:
1. Plug In USB-C cable (charging/HDMI) 2. Run "top" to verify that 3 kworker threads appear with high CPU usage. The fan will eventually kick in 3. Suspend the laptop (close the lid, press power button, press Fn+s, or manually suspend) and wait for the fan to completely turn off. Optionally unplug and plug in USB-C cable (sometimes helps). 4. Wake device from sleep. 5. Run "top" again, kworkers will be gone Now this does not work 100% of the time, as sometimes after waking from sleep the device still keeps the kworker threads up and running, but eventually after doing this they disappear until the next reboot. This workaround gets the job done for me, as long as I don't have to reboot often. Will share these findings on the bugzilla site as well. Hope it helps -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1987829 Title: LG Gram 12gen high CPU use when USB-C/TB is in use Status in linux package in Ubuntu: Confirmed Status in linux package in Fedora: New Bug description: LG Gram laptop 17Z90Q with a Core i7-1260P CPU. Whenever an external monitor is connected to USB-C/Thunderbolt 4, average load goes above 3.0 and the machine is getting very hot. Output from top -H shows a lot of kworker CPU usage: top - 11:45:06 up 33 min, 2 users, load average: 3,30, 3,08, 2,79 Threads: 1442 total, 2 running, 1440 sleeping, 0 stopped, 0 zombie %Cpu(s): 0,1 us, 3,7 sy, 0,0 ni, 96,1 id, 0,0 wa, 0,0 hi, 0,1 si, 0,0 st MiB Mem : 15684,6 total, 8510,2 free, 2580,8 used, 4593,6 buff/cache MiB Swap: 3815,0 total, 3815,0 free, 0,0 used. 11326,9 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ WCHAN COMMAND 7766 root 20 0 0 0 0 R 19,8 0,0 0:56.05 worker_th+ kworker/0:2-events 196 root 20 0 0 0 0 D 15,8 0,0 1:18.12 ec_guard kworker/u32:2+USBC000:00-con0 10237 root 20 0 0 0 0 I 12,9 0,0 0:26.44 worker_th+ kworker/0:0-events 1027 root 20 0 0 0 0 I 6,6 0,0 0:43.30 worker_th+ kworker/1:3-events 10971 root 20 0 0 0 0 I 4,0 0,0 0:00.20 worker_th+ kworker/15:0-events 175 root 20 0 0 0 0 I 2,3 0,0 0:03.24 worker_th+ kworker/11:1-events 2410 root 20 0 0 0 0 I 1,7 0,0 0:05.49 worker_th+ kworker/9:3-events Perf shows a lot of time spent inside handle_irq_event/acpi_ev_gpe_detect/acpi_hw_gpe_read. Additionally, kernel log is getting spammed with these lines every 4 seconds (but also without any USB-C device attached): [ 223.514304] ACPI Error: No handler for Region [XIN1] (00000000f2ad4f1f) [UserDefinedRegion] (20210730/evregion-130) [ 223.514323] ACPI Error: Region UserDefinedRegion (ID=143) has no handler (20210730/exfldio-261) [ 223.514337] Initialized Local Variables for Method [_TMP]: [ 223.514339] Local0: 0000000021495082 <Obj> Integer 0000000000000034 [ 223.514349] No Arguments are initialized for method [_TMP] [ 223.514354] ACPI Error: Aborting method \_SB.PC00.LPCB.LGEC.SEN2._TMP due to previous error (AE_NOT_EXIST) (20210730/psparse-529) ProblemType: Bug DistroRelease: Ubuntu 22.04 Package: linux-image-5.15.0-46-generic 5.15.0-46.49 ProcVersionSignature: Ubuntu 5.15.0-46.49-generic 5.15.39 Uname: Linux 5.15.0-46-generic x86_64 ApportVersion: 2.20.11-0ubuntu82.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: me 1678 F.... pulseaudio /dev/snd/controlC1: me 1678 F.... pulseaudio CRDA: N/A CasperMD5CheckResult: pass Date: Fri Aug 26 11:57:05 2022 InstallationDate: Installed on 2022-08-25 (1 days ago) InstallationMedia: Ubuntu 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220809.1) MachineType: LG Electronics 17Z90Q-G.AA78N ProcFB: 0 i915drmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.15.0-46-generic root=UUID=e2f96916-a67c-432e-b687-730071271216 ro quiet splash vt.handoff=7 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-5.15.0-46-generic N/A linux-backports-modules-5.15.0-46-generic N/A linux-firmware 20220329.git681281e4-0ubuntu3.4 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/06/2022 dmi.bios.release: 0.1 dmi.bios.vendor: Phoenix Technologies Ltd. dmi.bios.version: A1ZG0380 X64 dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: 17Z90Q dmi.board.vendor: LG Electronics dmi.board.version: FAB1 dmi.chassis.asset.tag: Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: LG Electronics dmi.chassis.version: 0.1 dmi.ec.firmware.release: 33.0 dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvrA1ZG0380X64:bd07/06/2022:br0.1:efr33.0:svnLGElectronics:pn17Z90Q-G.AA78N:pvr0.1:rvnLGElectronics:rn17Z90Q:rvrFAB1:cvnLGElectronics:ct10:cvr0.1:skuEVO: dmi.product.family: LG gram PC dmi.product.name: 17Z90Q-G.AA78N dmi.product.sku: EVO dmi.product.version: 0.1 dmi.sys.vendor: LG Electronics To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1987829/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
