From 9e4e249018d208678888bdf22f6b652728106528 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 28 Mar 2025 21:39:08 +0100 Subject: [PATCH] cpufreq: Reference count policy in cpufreq_update_limits() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Since acpi_processor_notify() can be called before registering a cpufreq driver or even in cases when a cpufreq driver is not registered at all, cpufreq_update_limits() needs to check if a cpufreq driver is present and prevent it from being unregistered. For this purpose, make it call cpufreq_cpu_get() to obtain a cpufreq policy pointer for the given CPU and reference count the corresponding policy object, if present. Fixes: 5a25e3f7cc53 ("cpufreq: intel_pstate: Driver-specific handling of _PPC updates") Closes: https://lore.kernel.org/linux-acpi/Z-ShAR59cTow0KcR@mail-itl Reported-by: Marek Marczykowski-Górecki Cc: All applicable Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar Link: https://patch.msgid.link/1928789.tdWV9SEqCh@rjwysocki.net --- drivers/cpufreq/cpufreq.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 0cf5a320bb5e8..3841c9da6cac3 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2809,6 +2809,12 @@ EXPORT_SYMBOL(cpufreq_update_policy); */ void cpufreq_update_limits(unsigned int cpu) { + struct cpufreq_policy *policy __free(put_cpufreq_policy); + + policy = cpufreq_cpu_get(cpu); + if (!policy) + return; + if (cpufreq_driver->update_limits) cpufreq_driver->update_limits(cpu); else -- 2.47.2