From: Johan Hovold <johan+linaro@xxxxxxxxxx>
commit b06730a571a9ff1ba5bd6b20bf9e50e5a12f1ec6 upstream.
The sanity check for an already mapped virq is done outside of the
irq_domain_mutex-protected section which means that an (unlikely) racing
association may not be detected.
Fix this by factoring out the association implementation, which will
also be used in a follow-on change to fix a shared-interrupt mapping
race.
Fixes: ddaf144c61da ("irqdomain: Refactor irq_domain_associate_many()")
Cc: stable@xxxxxxxxxxxxxxx # 3.11
Tested-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
Tested-by: Mark-PK Tsai <mark-pk.tsai@xxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230213104302.17307-2-johan+linaro@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/irq/irqdomain.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -516,8 +516,8 @@ void irq_domain_disassociate(struct irq_
irq_domain_clear_mapping(domain, hwirq);
}
-int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
- irq_hw_number_t hwirq)
+static int irq_domain_associate_locked(struct irq_domain *domain, unsigned int virq,
+ irq_hw_number_t hwirq)
{
struct irq_data *irq_data = irq_get_irq_data(virq);
int ret;
@@ -530,7 +530,6 @@ int irq_domain_associate(struct irq_doma
if (WARN(irq_data->domain, "error: virq%i is already associated", virq))
return -EINVAL;
- mutex_lock(&irq_domain_mutex);
irq_data->hwirq = hwirq;
irq_data->domain = domain;
if (domain->ops->map) {
@@ -547,7 +546,6 @@ int irq_domain_associate(struct irq_doma
}
irq_data->domain = NULL;
irq_data->hwirq = 0;
- mutex_unlock(&irq_domain_mutex);
return ret;
}
@@ -558,12 +556,23 @@ int irq_domain_associate(struct irq_doma
domain->mapcount++;
irq_domain_set_mapping(domain, hwirq, irq_data);
- mutex_unlock(&irq_domain_mutex);
irq_clear_status_flags(virq, IRQ_NOREQUEST);
return 0;
}
+
+int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
+ irq_hw_number_t hwirq)
+{
+ int ret;
+
+ mutex_lock(&irq_domain_mutex);
+ ret = irq_domain_associate_locked(domain, virq, hwirq);
+ mutex_unlock(&irq_domain_mutex);
+
+ return ret;
+}
EXPORT_SYMBOL_GPL(irq_domain_associate);
void irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base,
