Commit c87ddb6a authored Aug 24, 2011 by Abhijeet Dharmapurikar Committed by Matt Wagantall May 30, 2015

genirq: fix handle_nested_irq for lazy disable



When lazy disabling is implemented and an interrupt is disabled the
genirq code ends up marking it as IRQ_DISABLED in the descriptor.
The interrupt stays enabled in the controller.  If the interrupt
fires after disabling, the flow handlers namely handle_level_irq and
handle_edge_irq mask the interrupt in the controller.

This is not the case with handle_nested_irq. The interrupt stays enabled in
the controller and if it were a level interrupt it keeps firing only to be
ignored by handle_nested_irq.

Update handle_nested_irq to mask such an interrupt.

Change-Id: I9412e0bbf796c12a13b29802fe95fd544592bff5
CRs-Fixed: 300931
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>

parent d0033f02

kernel/irq/chip.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -305,6 +305,7 @@ void handle_nested_irq(unsigned int irq)
		{
		struct irq_desc *desc = irq_to_desc(irq);
		struct irqaction *action;
		int mask_this_irq = 0;
		irqreturn_t action_ret;

		might_sleep();
		@@ -317,6 +318,7 @@ void handle_nested_irq(unsigned int irq)
		action = desc->action;
		if (unlikely(!action \|\| irqd_irq_disabled(&desc->irq_data))) {
		desc->istate \|= IRQS_PENDING;
		mask_this_irq = 1;
		goto out_unlock;
		}

		@@ -332,6 +334,11 @@ void handle_nested_irq(unsigned int irq)

		out_unlock:
		raw_spin_unlock_irq(&desc->lock);
		if (unlikely(mask_this_irq)) {
		chip_bus_lock(desc);
		mask_irq(desc);
		chip_bus_sync_unlock(desc);
		}
		}
		EXPORT_SYMBOL_GPL(handle_nested_irq);