Am Freitag, 23. September 2005 16:53 schrieb Duncan Sands:
> > > A driver using spin_lock_irq() in a tasklet is buggy. You can always use
> > > irqsave. It will just be slower. But in a tasklet or interrupt handler
> > > spin_lock() will do. Basically these locks differ in whether they shut 
> > > down
> > > irq processing on the local CPU. In interrupt it is down and must not be
> > > reenabled. Therefore spin_lock_irq() is deadly.
> > 
> > This may depend on the particular architecture or platform.  On x86,
> > general interrupts are not always disabled during interrupt handlers.  
> > Only the particular IRQ line being handled.
> 
> What's more, in the particular case of urb completion callbacks there is
> no guarantee that the callback is even called from an interrupt.

but it is always called with local interrupts disabled. We guarantee this in
all cases.

        Regards
                Oliver


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