On Mon, Mar 06, 2017 at 07:05:39PM +0100, Thomas Gleixner wrote:
> On Mon, 6 Mar 2017, Charles Keepax wrote:
>
> > When an IRQ is nested the nested handler is called directly from within the
> > threaded handler of the parent IRQ, however, the code in handle_nested_irq
> > only calls a single handler. This means when a shared IRQ is nested only
> > the first of the shared IRQ handlers will be run. This patch adds a loop
> > to move through and process all the handlers associated with the IRQ in
> > handle_nested_irq.
>
> That was never meant to deal with nested shaed interrupts, so the $subject
> is misleading. This is not a fix, it's a functional extension.
>
> Aside of that, please structure the changelog in paragraphs instead of one
> big lump.
>
> 1) Context
> 2) Problem
> 3) Solution
>
> See also Documentation/process/submitting-patches.rst and please search
> there for "This patch" .....
>
> > @@ -348,9 +348,12 @@ void handle_nested_irq(unsigned int irq)
> > irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
> > raw_spin_unlock_irq(&desc->lock);
> >
> > - action_ret = action->thread_fn(action->irq, action->dev_id);
> > - if (!noirqdebug)
> > - note_interrupt(desc, action_ret);
> > + do {
>
> for_each_action_of_desc() please
>
> > + action_ret = action->thread_fn(action->irq, action->dev_id);
> > + if (!noirqdebug)
> > + note_interrupt(desc, action_ret);
>
> That's wrong. See __handle_irq_event_percpu() for the correct handling of
> shared interrupts vs. note_interrupt()
>
Thanks for the pointers, I will look at those and respin the
patch.
Thanks,
Charles
