Re: [PATCH] cpufreq: acpi-cpufreq: Initialize cmd.val in drv_read()

On 8/10/2026 2:10 PM, lirongqing wrote:
> From: Li RongQing <[email protected]>
> 
> In drv_read(), struct drv_cmd cmd is allocated on the stack with .val left
> uninitialized. If smp_call_function_any() fails, do_drv_read() will not
> run to populate cmd.val. As a result, drv_read() would return uninitialized
> stack data.
> 
> Fix this by explicitly initializing .val to 0 when declaring cmd.
> 
> Signed-off-by: Li RongQing <[email protected]>
> ---
>   drivers/cpufreq/acpi-cpufreq.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
> index cd2ca87..6c7ece9 100644
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -308,6 +308,7 @@ static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
>   	struct acpi_processor_performance *perf = to_perf_data(data);
>   	struct drv_cmd cmd = {
>   		.reg = &perf->control_register,
> +		.val = 0,

Will the compiler handle this automatically?

https://en.cppreference.com/c/language/initialization


>   		.func.read = data->cpu_freq_read,
>   	};
>   	int err;


-- 
Thx and BRs,
Zhongqiu Han