Re: [PATCH] int340X/processor_thermal_device: Fix proc_thermal_rapl_remove()

[Rafael J. Wysocki]

On Mon, Jul 22, 2019 at 12:23 PM Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
>
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Passing 0 to cpuhp_remove_state() triggers the BUG_ON() in
> __cpuhp_remove_state_cpuslocked() and the argument passed to
> powercap_unregister_control_type() is expected to be a valid
> pointer, so avoid calling these functions with incorrect
> arguments from proc_thermal_rapl_remove().
>
> Fixes: 555c45fe0d04 ("int340X/processor_thermal_device: add support for MMIO RAPL")
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Any comments?

If not, I'll queue this up along with the other RAPL-related fix
(https://patchwork.kernel.org/patch/11050999/).

> ---
>  drivers/thermal/intel/int340x_thermal/processor_thermal_device.c |    4 ++++
>  1 file changed, 4 insertions(+)
>
> Index: linux-pm/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> ===================================================================
> --- linux-pm.orig/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> +++ linux-pm/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> @@ -487,6 +487,7 @@ static int proc_thermal_rapl_add(struct
>                                 rapl_mmio_cpu_online, rapl_mmio_cpu_down_prep);
>         if (ret < 0) {
>                 powercap_unregister_control_type(rapl_mmio_priv.control_type);
> +               rapl_mmio_priv.control_type = NULL;
>                 return ret;
>         }
>         rapl_mmio_priv.pcap_rapl_online = ret;
> @@ -496,6 +497,9 @@ static int proc_thermal_rapl_add(struct
>
>  static void proc_thermal_rapl_remove(void)
>  {
> +       if (IS_ERR_OR_NULL(rapl_mmio_priv.control_type))
> +               return;
> +
>         cpuhp_remove_state(rapl_mmio_priv.pcap_rapl_online);
>         powercap_unregister_control_type(rapl_mmio_priv.control_type);
>  }
>
>
>