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    SubjectRe: [PATCH 4/7] [hrtimers] Fix posix-timer requeue race

    On Fri, 20 Jan 2006, Thomas Gleixner wrote:

    > CPU0 expires a posix-timer and runs the callback function.
    > The signal is queued.
    > After releasing the posix-timer lock and before returning to
    > hrtimer_run_queue CPU0 gets interrupted.
    > CPU1 delivers the queued signal and rearms the timer.
    > CPU0 comes back to hrtimer_run_queue and sets the timer state to expired.
    > The next modification of the timer can result in an oops, because the state
    > information is wrong.

    Thomas, this is exactly what I meant with overloaded state machines,
    enumerated states are very hard to get right with concurrent processes.
    Please get rid of the state field and at least use a flag field instead.

    bye, Roman
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