From: Fushuai Wang Date: Wed, 20 May 2026 03:21:19 +0000 (+0800) Subject: cpufreq: intel_pstate: Sync policy->cur during CPU offline X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=bcbdaa1086c25a8a5d48e04e1b82fdfb0682b681;p=thirdparty%2Fkernel%2Flinux.git cpufreq: intel_pstate: Sync policy->cur during CPU offline When a CPU goes offline with HWP disabled, intel_pstate_set_min_pstate() sets the MSR_IA32_PERF_CTL to minimum frequency to prevent SMT siblings from being restricted. However, the policy->cur value was not updated, leaving it at the previous value. When the CPU comes back online, governor->limits() checks if target_freq equals policy->cur and skips the frequency adjustment if they match. Since policy->cur still holds the previous value, the governor does not call cpufreq_driver->target to update MSR_IA32_PERF_CTL. Fix this by synchronizing policy->cur with the hardware state when setting minimum pstate during CPU offline. Fixes: bb18008f8086 ("intel_pstate: Set core to min P state during core offline") Cc: stable@vger.kernel.org # 3.15+ Suggested-by: Srinivas Pandruvada Signed-off-by: Fushuai Wang [ rjw: Subject refinement ] Link: https://patch.msgid.link/20260520032119.30615-1-fushuai.wang@linux.dev Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 1f093e3464301..0fbbdbd5765cf 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2984,10 +2984,12 @@ static int intel_cpufreq_cpu_offline(struct cpufreq_policy *policy) * from getting to lower performance levels, so force the minimum * performance on CPU offline to prevent that from happening. */ - if (hwp_active) + if (hwp_active) { intel_pstate_hwp_offline(cpu); - else + } else { intel_pstate_set_min_pstate(cpu); + policy->cur = cpu->pstate.min_freq; + } intel_pstate_exit_perf_limits(policy);