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    Subject[PATCH 1/3] fix kthread_create() vs freezer theoretical race
    kthread() sleeps in TASK_INTERRUPTIBLE state waiting for the first wakeup.
    In theory, this wakeup may come from freeze_process()->signal_wake_up(),
    so the task can disappear even before kthread_create() sets its ->comm.

    Change kthread() to use TASK_UNINTERRUPTIBLE.

    Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>

    --- 2.6.21-rc5/kernel/kthread.c~0_FREEZER 2007-04-13 14:52:44.000000000 +0400
    +++ 2.6.21-rc5/kernel/kthread.c 2007-04-13 15:36:43.000000000 +0400
    @@ -70,7 +70,7 @@ static int kthread(void *_create)
    data = create->data;

    /* OK, tell user we're spawned, wait for stop or wakeup */
    - __set_current_state(TASK_INTERRUPTIBLE);
    + __set_current_state(TASK_UNINTERRUPTIBLE);
    complete(&create->started);
    schedule();

    @@ -174,7 +174,7 @@ EXPORT_SYMBOL(kthread_create);
    */
    void kthread_bind(struct task_struct *k, unsigned int cpu)
    {
    - BUG_ON(k->state != TASK_INTERRUPTIBLE);
    + BUG_ON(k->state != TASK_UNINTERRUPTIBLE);
    /* Must have done schedule() in kthread() before we set_task_cpu */
    wait_task_inactive(k);
    set_task_cpu(k, cpu);
    -
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