On 9/1/21 3:47 AM, Ard Biesheuvel wrote:
> Registering an IRQ requires the string buffer containing the name to
> remain allocated, as the name is not copied into another buffer.
>
> So let's add a irq_name field to the data struct instead, which is
> guaranteed to have the appropriate lifetime.
>
> Cc: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
> Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> Cc: Andy Gross <agross@xxxxxxxxxx>
> Cc: linux-arm-msm@xxxxxxxxxxxxxxx
> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> ---
> I'm not following msm development closely, so apologies if this was
> already fixed, or if this is not based on the right tree.
>
> This fixes a crash on my Yoga C630 when reading /proc/interrupts.
>
> drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index 3cc27d9e2ed1..6613228fe68c 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
> /* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
> spinlock_t throttle_lock;
> int throttle_irq;
> + char irq_name[15];
> bool cancel_throttle;
> };
>
> @@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
> {
> struct qcom_cpufreq_data *data = policy->driver_data;
> struct platform_device *pdev = cpufreq_get_driver_data();
> - char irq_name[15];
> int ret;
>
> /*
> @@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
> spin_lock_init(&data->throttle_lock);
> INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
>
> - snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
> + snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
> ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
> - IRQF_ONESHOT, irq_name, data);
> + IRQF_ONESHOT, data->irq_name, data);
> if (ret) {
> - dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
> + dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
> return 0;
> }
>
I haven't experienced the crash here, but I also tested the patch on my
C630, and still don't see the issue so, if you want:
Tested-By: Steev Klimaszewski <steev@xxxxxxxx>
