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@vger.kernel.org # 3.11 Tested-by: Hsin-Yi Wang hsinyi@chromium.org Tested-by: Mark-PK Tsai mark-pk.tsai@mediatek.com Signed-off-by: Johan Hovold johan+linaro@kernel.org --- kernel/irq/irqdomain.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 798a9042421f..561689a3f050 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -559,8 +559,8 @@ static void irq_domain_disassociate(struct irq_domain *domain, unsigned int 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; @@ -573,7 +573,6 @@ int irq_domain_associate(struct irq_domain *domain, unsigned int virq, 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) { @@ -590,7 +589,6 @@ int irq_domain_associate(struct irq_domain *domain, unsigned int virq, } irq_data->domain = NULL; irq_data->hwirq = 0; - mutex_unlock(&irq_domain_mutex); return ret; }

@@ -601,12 +599,23 @@ int irq_domain_associate(struct irq_domain *domain, unsigned int virq,

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,