| From | Juri Lelli <> | Subject | [RFC PATCH 14/19] cpufreq: fix locking of policy->rwsem in cpufreq_offline_finish | Date | Mon, 11 Jan 2016 17:35:55 +0000 |
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There are paths in cpufreq_offline_prepare where policy is used, but its rwsem is not held.
Fix it.
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Juri Lelli <juri.lelli@arm.com> --- drivers/cpufreq/cpufreq.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 91158b0..ba452c3 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1381,9 +1381,13 @@ static void cpufreq_offline_finish(unsigned int cpu) return; } + down_write(&policy->rwsem); + /* Only proceed for inactive policies */ - if (!policy_is_inactive(policy)) + if (!policy_is_inactive(policy)) { + up_write(&policy->rwsem); return; + } /* If cpu is last user of policy, free policy */ if (has_target()) { @@ -1392,6 +1396,8 @@ static void cpufreq_offline_finish(unsigned int cpu) pr_err("%s: Failed to exit governor\n", __func__); } + up_write(&policy->rwsem); + /* * Perform the ->exit() even during light-weight tear-down, * since this is a core component, and is essential for the -- 2.2.2
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