The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ed38eb49d101e829ae0f8c0a0d3bf5cb6bcbc6b2 Mon Sep 17 00:00:00 2001

From: "Rafael J. Wysocki" rafael.j.wysocki@intel.com Date: Wed, 17 Nov 2021 14:57:31 +0100 Subject: [PATCH] cpufreq: intel_pstate: Fix active mode offline/online EPP handling

After commit 4adcf2e5829f ("cpufreq: intel_pstate: Add ->offline and ->online callbacks") the EPP value set by the "performance" scaling algorithm in the active mode is not restored after an offline/online cycle which replaces it with the saved EPP value coming from user space.

Address this issue by forcing intel_pstate_hwp_set() to set a new EPP value when it runs first time after online.

Fixes: 4adcf2e5829f ("cpufreq: intel_pstate: Add ->offline and ->online callbacks") Link: https://lore.kernel.org/linux-pm/adc7132c8655bd4d1c8b6129578e931a14fe1db2.ca... Reported-by: Srinivas Pandruvada srinivas.pandruvada@linux.intel.com Cc: 5.9+ stable@vger.kernel.org # 5.9+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 1088ff350159..1bc00645b656 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1006,6 +1006,12 @@ static void intel_pstate_hwp_offline(struct cpudata *cpu) */ value &= ~GENMASK_ULL(31, 24); value |= HWP_ENERGY_PERF_PREFERENCE(cpu->epp_cached); + /* + * However, make sure that EPP will be set to "performance" when + * the CPU is brought back online again and the "performance" + * scaling algorithm is still in effect. + */ + cpu->epp_policy = CPUFREQ_POLICY_UNKNOWN; }

/*