github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-11 20:13:02 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

cpufreq: initialize policy rwsem before sysfs publication

Browse Source 
cpufreq_policy_alloc() initializes policy->rwsem after
kobject_init_and_add() has created the policy sysfs directory and its
default attributes. A sysfs access can therefore reach a policy callback
before the semaphore has been initialized.

Initialize policy->rwsem before publishing the policy kobject so sysfs
callbacks always see an initialized semaphore.

Fixes: 2fc3384dc7 ("cpufreq: Initialize policy->kobj while allocating policy")
Cc: All Applicable <stable@vger.kernel.org>
Link: https://lore.kernel.org/all/20260830155301.2713780-1-runyu.xiao@seu.edu.cn/
Reviewed-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20260902041915.3453421-1-runyu.xiao@seu.edu.cn
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Runyu Xiao 2026-09-02 12:19:15 +08:00 committed by Rafael J. Wysocki
parent cee9395acd
commit 3e5d1bf4bd
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/cpufreq/cpufreq.c
View File

@ -1258,6 +1258,8 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
goto err_free_rcpumask;
init_rwsem(&policy->rwsem);
init_completion(&policy->kobj_unregister);
ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
cpufreq_global_kobject, "policy%u", cpu);
@ -1272,8 +1274,6 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
goto err_free_real_cpus;
}
init_rwsem(&policy->rwsem);
freq_constraints_init(&policy->constraints);
policy->nb_min.notifier_call = cpufreq_notifier_min;