Re: /proc/timer_list and weird behavior with dropbear

From: Nathan Zimmer
Date: Fri Jul 19 2013 - 16:33:29 EST


On Fri, Jul 19, 2013 at 07:03:54PM +0200, Holger Hans Peter Freyther wrote:
> On Fri, Jul 19, 2013 at 10:45:15AM -0500, Nathan Zimmer wrote:
>
> > I hadn't noticed anything.
> > Let me try your program and see what I may have missed.
>
> Hi,
>
> I neither know the semantics of the timer_list nor how to use
> seq_file correctly. What happens is that timer_list_next will only
> be called once. This means that iter->cpu will never be increased.
>
> This just moves to the next CPU when stop is called (e.g. nothing
> was added once the print_tickdevice was printed). Do you think
> this could be correct?
>
>
>
> diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
> index 3bdf283..8d36a3d 100644
> --- a/kernel/time/timer_list.c
> +++ b/kernel/time/timer_list.c
> @@ -327,8 +327,10 @@ static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset)
> return timer_list_start(file, offset);
> }
>
> -static void timer_list_stop(struct seq_file *seq, void *v)
> +static void timer_list_stop(struct seq_file *file, void *v)
> {
> + struct timer_list_iter *iter = file->private;
> + iter->cpu = cpumask_next(iter->cpu, cpu_online_mask);
> }
>
> static const struct seq_operations timer_list_sops = {


I think this would be an acceptable fix.
It work file locally. Could you check it out to see if it behaves?

Nate
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