On 5/10/23 02:00, Kevin Locke wrote: > 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. Thanks for reporting this issue. The patch moved the setup of acpi-cpufreq from being done directly in its module init function to going through the probe logic. The reported warning newly comes from call_driver_probe() when the probe fails. One immediate option that I can see to silence this warning would be to change the return code for this case in acpi_cpufreq_probe() from -EEXIST to -ENODEV/ENXIO. Function call_driver_probe() then prints only a debug message about the probe rejecting the device. -- Petr
