diff mbox series

[v3,05/19] irqdomain: Fix disassociation race

Message ID 20221209140150.1453-6-johan+linaro@kernel.org
State New
Headers
Series irqdomain: fix mapping race and clean up locking |

Commit Message

Johan Hovold Dec. 9, 2022, 2:01 p.m. UTC 
  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: 9dc6be3d4193 ("genirq/irqdomain: Add map counter")
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 kernel/irq/irqdomain.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index b2087f55a1ac..23f5919e58b7 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -537,6 +537,9 @@  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 */
@@ -556,6 +559,8 @@  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(struct irq_domain *domain, unsigned int virq,