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This is > intentional to prevent stale value of last CPPC_REQ from kernels that > are not aware of bios_min_perf to be mistakenly interpreted as the > bios_min_perf during kexec boot. Is it a real valid case we need to worry about for someone kexec'ing between kernels that are aware of this vs not aware of it? During kernel development; sure this might happen. But I would think once this is available in mainline any of the distro kernels will have picked this up and people will start with a distro kernel with support, or they'll start with a distro kernel without and upgrade to one with. I can't imagine a case people will go the other way. > > Work around this limitation by stashing the state of CPPC_REQ during > suspend / offlining in cpudata and then only programming the > bios_min_perf into CPPC_REQ while keeping the rest of the bits as 0. > > Resume / onlining callbacks use the stashed state to restore the > CPPC_REQ before the CPU resumes normal operation. > > Patches are prepared on top of linux-pm:bleeding-edge at commit > 0e4eef86f0f4d ("Merge branch 'thermal-intel' into bleeding-edge"). >