If you’re using a ThinkPad laptop with Ubuntu Linux, you might be probably also using a package called acpi-call-dkms. This package installs a kernel module that provides a way for software to do ACPI calls. One of the most popular program to use it – is TLP.
Unfortunately with the latest release of Ubuntu – 21.10 Impish Indri this package is partially broken, as it doesn’t seem to work with Linux kernel 5.13 because of a bug.
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