When maxcpus=1 is appended the BP is responsible for re-enabling the HWP - because currently only the APs invoke intel_pstate_hwp_enable() during their online process - which might put the system into unstable state after resume.
Fix this by enabling the HWP explicitly on BP during resume. Reported-by: Doug Smythies <dsmyth...@telus.net> Suggested-by: Srinivas Pandruvada <srinivas.pandruv...@linux.intel.com> Signed-off-by: Yu Chen <yu.c.c...@intel.com> --- drivers/cpufreq/intel_pstate.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 93a0e88bef76..89f637e8439c 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -779,6 +779,8 @@ static int intel_pstate_hwp_save_state(struct cpufreq_policy *policy) return 0; } +static void intel_pstate_hwp_enable(struct cpudata *cpudata); + static int intel_pstate_resume(struct cpufreq_policy *policy) { if (!hwp_active) @@ -786,6 +788,8 @@ static int intel_pstate_resume(struct cpufreq_policy *policy) mutex_lock(&intel_pstate_limits_lock); + if (!policy->cpu) + intel_pstate_hwp_enable(all_cpu_data[policy->cpu]); all_cpu_data[policy->cpu]->epp_policy = 0; intel_pstate_hwp_set(policy->cpu); -- 2.13.6