6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jinjie Ruan ruanjinjie@huawei.com
[ Upstream commit b51eb0874d8170028434fbd259e80b78ed9b8eca ]
cppc_get_cpu_power() return 0 if the policy is NULL. Then in em_create_perf_table(), the later zero check for power is not valid as power is uninitialized. As Quentin pointed out, kernel energy model core check the return value of active_power() first, so if the callback failed it should tell the core. So return -EINVAL to fix it.
Fixes: a78e72075642 ("cpufreq: CPPC: Fix possible null-ptr-deref for cpufreq_cpu_get_raw()") Signed-off-by: Jinjie Ruan ruanjinjie@huawei.com Suggested-by: Quentin Perret qperret@google.com Signed-off-by: Viresh Kumar viresh.kumar@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/cpufreq/cppc_cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 05a8418485079..c8447ecad797e 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -429,7 +429,7 @@ static int cppc_get_cpu_power(struct device *cpu_dev,
policy = cpufreq_cpu_get_raw(cpu_dev->id); if (!policy) - return 0; + return -EINVAL;
cpu_data = policy->driver_data; perf_caps = &cpu_data->perf_caps;