Commit 3f883c38 authored by Johan Hovold's avatar Johan Hovold Committed by Marc Zyngier
Browse files

irqdomain: Fix disassociation race 



The global irq_domain_mutex is held when mapping interrupts from
non-hierarchical domains but currently not when disposing them.

This specifically means that updates of the domain mapcount is racy
(currently only used for statistics in debugfs).

Make sure to hold the global irq_domain_mutex also when disposing
mappings from non-hierarchical domains.

Fixes: 9dc6be3d ("genirq/irqdomain: Add map counter")
Cc: stable@vger.kernel.org      # 4.13
Tested-by: default avatarHsin-Yi Wang <hsinyi@chromium.org>
Tested-by: default avatarMark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: default avatarJohan Hovold <johan+linaro@kernel.org>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230213104302.17307-3-johan+linaro@kernel.org
parent b06730a5

kernel/irq/irqdomain.c

+5 −0
Original line number Diff line number Diff line
@@ -538,6 +538,9 @@ static void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq) 
		return;



	hwirq = irq_data->hwirq;



	mutex_lock(&irq_domain_mutex);



	irq_set_status_flags(irq, IRQ_NOREQUEST);



	/* remove chip and handler */
@@ -557,6 +560,8 @@ static void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq) 


	/* Clear reverse map for this hwirq */

	irq_domain_clear_mapping(domain, hwirq);



	mutex_unlock(&irq_domain_mutex);

}



static int irq_domain_associate_locked(struct irq_domain *domain, unsigned int virq,