[PATCH v3 05/14] irqchip/irq-bcm7038-l1: Restrict affinity setting to MIPS

From: Florian Fainelli
Date: Tue Sep 28 2021 - 14:22:46 EST


Only MIPS based platforms using this interrupt controller as first level
interrupt controller can actually change the affinity of interrupts by
re-programming the affinity mask of the interrupt controller and use
another word group to have another CPU process the interrupt.

When this interrupt is used as a second level interrupt controller on
ARM/ARM64 there is no way to change the interrupt affinity. This fixes a
NULL pointer de-reference while trying to change the affinity since
there is only a single word group in that case, and we would have been
overruning the intc->cpus[] array.

Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
drivers/irqchip/irq-bcm7038-l1.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/irqchip/irq-bcm7038-l1.c b/drivers/irqchip/irq-bcm7038-l1.c
index 3c4e348c661e..357570dd8780 100644
--- a/drivers/irqchip/irq-bcm7038-l1.c
+++ b/drivers/irqchip/irq-bcm7038-l1.c
@@ -191,6 +191,7 @@ static void bcm7038_l1_mask(struct irq_data *d)
raw_spin_unlock_irqrestore(&intc->lock, flags);
}

+#if defined(CONFIG_MIPS) && defined(CONFIG_SMP)
static int bcm7038_l1_set_affinity(struct irq_data *d,
const struct cpumask *dest,
bool force)
@@ -217,6 +218,7 @@ static int bcm7038_l1_set_affinity(struct irq_data *d,

return 0;
}
+#endif

static int __init bcm7038_l1_init_one(struct device_node *dn,
unsigned int idx,
@@ -365,7 +367,9 @@ static struct irq_chip bcm7038_l1_irq_chip = {
.name = "bcm7038-l1",
.irq_mask = bcm7038_l1_mask,
.irq_unmask = bcm7038_l1_unmask,
+#if defined(CONFIG_SMP) && defined(CONFIG_MIPS)
.irq_set_affinity = bcm7038_l1_set_affinity,
+#endif
#ifdef CONFIG_PM_SLEEP
.irq_set_wake = bcm7038_l1_set_wake,
#endif
--
2.25.1