• Thomas Gleixner's avatar
    clockevents: prevent endless loop lockup · 1fb9b7d2
    Thomas Gleixner authored
    The C1E/HPET bug reports on AMDX2/RS690 systems where tracked down to a
    too small value of the HPET minumum delta for programming an event.
    
    The clockevents code needs to enforce an interrupt event on the clock event
    device in some cases. The enforcement code was stupid and naive, as it just
    added the minimum delta to the current time and tried to reprogram the device.
    When the minimum delta is too small, then this loops forever.
    
    Add a sanity check. Allow reprogramming to fail 3 times, then print a warning
    and double the minimum delta value to make sure, that this does not happen again.
    Use the same function for both tick-oneshot and tick-broadcast code.
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    1fb9b7d2
tick-oneshot.c 3.49 KB