This still happens on a fresh Focal install using linux- image-5.4.0-26-generic version 5.4.0-26.30
** Also affects: linux-signed (Ubuntu) Importance: Undecided Status: New ** Tags removed: bionic ** Tags added: focal -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-signed in Ubuntu. https://bugs.launchpad.net/bugs/1861028 Title: Fan control stops working on resume for Dell Precision Status in linux-signed package in Ubuntu: New Status in linux-signed-hwe package in Ubuntu: New Bug description: This system is a Dell Precision Tower 3420 with the latest BIOS 2.13.1, kernel version is 5.3.0-26-generic (HWE, bionic) Freshly booting the system and doing something CPU intensive, like compiling a kernel, cause the CPU fan to ramp up as expected and the CPU temperatures remain acceptable. After suspending (ie Alt-clicking the power button in Unity) and then resuming, the CPU fan runs at a permanent low frequency and does not ramp up. Doing something like a kernel build causes the CPU to overheat and logs messages to dmesg. Investigating I see that the dell_smm_hwmon driver has a 'temp2' input that reflects the CPU temperature. Upon power up the value works properly, after resume it returns -ENODATA. The other sensor for CPU temperature (thermal_zone3/temp, x86_pkg_temp) still works correctly. Blacklisting the dell_smm_hwmon driver has no impact Dell Precisions are listed as compatible with Ubuntu, and this system was purchased with Ubuntu pre-installed from Dell, so it is surpsing something so basic isn't working? ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: linux-image-5.3.0-26-generic 5.3.0-26.28~18.04.1 ProcVersionSignature: Ubuntu 5.3.0-26.28~18.04.1-generic 5.3.13 Uname: Linux 5.3.0-26-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.9 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Mon Jan 27 15:48:39 2020 InstallationDate: Installed on 2018-08-04 (540 days ago) InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725) SourcePackage: linux-signed-hwe UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed/+bug/1861028/+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