On Thu, 2023-03-16 at 16:10 +0100, Petr Pavlu wrote: > The patch extends the ACPI parsing logic to check the ACPI namespace if > the PPC or PCC interface is present and creates a virtual platform > device for each if it is available. The acpi-cpufreq and pcc-cpufreq > drivers are then updated to map to these devices. > > This allows to try loading acpi-cpufreq and pcc-cpufreq only once during > boot and only if a given interface is available in the firmware. As a result of this patch (691a637123470bfe63bccf5836ead40fac4c7fab) my ThinkPad T430 with an i5-3320M CPU configured with CONFIG_X86_INTEL_PSTATE=y and CONFIG_X86_ACPI_CPUFREQ=m (Debian's amd64 kernel config) now logs kernel: acpi-cpufreq: probe of acpi-cpufreq failed with error -17 during boot. Presumably this occurs because loading acpi-cpufreq returns -EEXIST when intel-pstate is already loaded (or built-in, as in this case). I'm unsure why the message was not printed before; perhaps a difference between driver probing for platform and cpu bus types? Although the error message is not wrong, it may lead to unnecessary investigation by sysadmins, as it did for me. I thought it was worth reporting so you can consider whether the change is desirable. Cheers, Kevin
