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    SubjectRe: 2.6.39-rc4+: Kernel leaking memory during FS scanning, regression?
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    On Fri, Apr 29, 2011 at 12:02 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
    > On Thu, 28 Apr 2011, john stultz wrote:
    >> On Thu, 2011-04-28 at 23:04 +0200, Thomas Gleixner wrote:
    >> > /me suspects hrtimer changes to be the real culprit.
    >>
    >> I'm not seeing anything on right off, but it does smell like
    >> e06383db9ec591696a06654257474b85bac1f8cb would be where such an issue
    >> would crop up.
    >>
    >> Bruno, could you try checking out e06383db9ec, confirming it still
    >> occurs (and then maybe seeing if it goes away at e06383db9ec^1)?
    >>
    >> I'll keep digging in the meantime.
    >
    > I found the bug already. The problem is that sched_init() calls
    > init_rt_bandwidth() which calls hrtimer_init() _BEFORE_
    > hrtimers_init() is called.
    >
    > That was unnoticed so far as the CLOCK id to hrtimer base conversion
    > was hardcoded. Now we use a table which is set up at hrtimers_init(),
    > so the bandwith hrtimer ends up on CLOCK_REALTIME because the table is
    > in the bss.
    >
    > The patch below fixes this, by providing the table statically rather
    > than runtime initialized. Though that whole ordering wants to be
    > revisited.
    >
    > Thanks,
    >
    >        tglx
    >
    > --- linux-2.6.orig/kernel/hrtimer.c
    > +++ linux-2.6/kernel/hrtimer.c
    > @@ -81,7 +81,11 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base,
    >        }
    >  };
    >
    > -static int hrtimer_clock_to_base_table[MAX_CLOCKS];
    > +static int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
    > +       [CLOCK_REALTIME] = HRTIMER_BASE_REALTIME,
    > +       [CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC,
    > +       [CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME,
    > +};
    >
    >  static inline int hrtimer_clockid_to_base(clockid_t clock_id)
    >  {
    > @@ -1722,10 +1726,6 @@ static struct notifier_block __cpuinitda
    >
    >  void __init hrtimers_init(void)
    >  {
    > -       hrtimer_clock_to_base_table[CLOCK_REALTIME] = HRTIMER_BASE_REALTIME;
    > -       hrtimer_clock_to_base_table[CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC;
    > -       hrtimer_clock_to_base_table[CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME;
    > -
    >        hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE,
    >                          (void *)(long)smp_processor_id());
    >        register_cpu_notifier(&hrtimers_nb);
    >

    Will you send this as a separate patch?

    Please also feel free to add:

    Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

    If you like also a Reported-by... as the issue is not new, I have
    first reported it here [1].

    - Sedat -

    [1] http://lkml.org/lkml/2011/3/25/97
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