On Thu, Oct 5, 2017 at 3:54 AM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> In preparation for unconditionally passing the struct timer_list pointer to
> all timer callbacks, switch to using the new timer_setup() and from_timer()
> to pass the timer pointer explicitly. Moves timer structure off stack and
> into struct ips_driver.
Pushed to my testing queue, thanks!
>
> Cc: Darren Hart <dvhart@xxxxxxxxxxxxx>
> Cc: Andy Shevchenko <andy@xxxxxxxxxxxxx>
> Cc: platform-driver-x86@xxxxxxxxxxxxxxx
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
> This requires commit 686fef928bba ("timer: Prepare to change timer
> callback argument type") in v4.14-rc3, but should be otherwise
> stand-alone.
> ---
> drivers/platform/x86/intel_ips.c | 15 +++++++--------
> 1 file changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/platform/x86/intel_ips.c b/drivers/platform/x86/intel_ips.c
> index 58dcee562d64..056afb731d79 100644
> --- a/drivers/platform/x86/intel_ips.c
> +++ b/drivers/platform/x86/intel_ips.c
> @@ -300,6 +300,7 @@ struct ips_driver {
> struct task_struct *monitor;
> struct task_struct *adjust;
> struct dentry *debug_root;
> + struct timer_list timer;
>
> /* Average CPU core temps (all averages in .01 degrees C for precision) */
> u16 ctv1_avg_temp;
> @@ -942,9 +943,10 @@ static u32 calc_avg_power(struct ips_driver *ips, u32 *array)
> return avg;
> }
>
> -static void monitor_timeout(unsigned long arg)
> +static void monitor_timeout(struct timer_list *t)
> {
> - wake_up_process((struct task_struct *)arg);
> + struct ips_driver *ips = from_timer(ips, t, timer);
> + wake_up_process(ips->monitor);
> }
>
> /**
> @@ -961,7 +963,6 @@ static void monitor_timeout(unsigned long arg)
> static int ips_monitor(void *data)
> {
> struct ips_driver *ips = data;
> - struct timer_list timer;
> unsigned long seqno_timestamp, expire, last_msecs, last_sample_period;
> int i;
> u32 *cpu_samples, *mchp_samples, old_cpu_power;
> @@ -1049,8 +1050,7 @@ static int ips_monitor(void *data)
> schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));
> last_sample_period = IPS_SAMPLE_PERIOD;
>
> - setup_deferrable_timer_on_stack(&timer, monitor_timeout,
> - (unsigned long)current);
> + timer_setup(&ips->timer, monitor_timeout, TIMER_DEFERRABLE);
> do {
> u32 cpu_val, mch_val;
> u16 val;
> @@ -1107,7 +1107,7 @@ static int ips_monitor(void *data)
> expire = jiffies + msecs_to_jiffies(IPS_SAMPLE_PERIOD);
>
> __set_current_state(TASK_INTERRUPTIBLE);
> - mod_timer(&timer, expire);
> + mod_timer(&ips->timer, expire);
> schedule();
>
> /* Calculate actual sample period for power averaging */
> @@ -1116,8 +1116,7 @@ static int ips_monitor(void *data)
> last_sample_period = 1;
> } while (!kthread_should_stop());
>
> - del_timer_sync(&timer);
> - destroy_timer_on_stack(&timer);
> + del_timer_sync(&ips->timer);
>
> dev_dbg(&ips->dev->dev, "ips-monitor thread stopped\n");
>
> --
> 2.7.4
>
>
> --
> Kees Cook
> Pixel Security
--
With Best Regards,
Andy Shevchenko
