[PATCH v2 3/3] x86: devicetree: fix device IRQ settings in DT

From: Ivan Gorinov
Date: Wed Feb 28 2018 - 21:53:14 EST


IRQ parameters for SoC devices connected directly to I/O APIC lines
(without PCI IRQ routing) may be specified in the Device Tree.
Called from DT IRQ parser, irq_create_fwspec_mapping() calls
irq_domain_alloc_irqs() with a pointer to irq_fwspec structure as @arg.
But x86-specific DT IRQ allocation code casts @arg to of_phandle_args
structure pointer and crashes trying to read IRQ parameters.

Signed-off-by: Ivan Gorinov <ivan.gorinov@xxxxxxxxx>
---
Âarch/x86/kernel/devicetree.c | 13 ++++++++-----
Â1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index ef1cd85..b8b5874 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -215,19 +215,22 @@ static struct of_ioapic_type of_ioapic_type[] =
Âstatic int dt_irqdomain_alloc(struct irq_domain *domain, unsigned int virq,
 ÂÂÂÂÂÂunsigned int nr_irqs, void *arg)
Â{
- struct of_phandle_args *irq_data = (void *)arg;
+ struct irq_fwspec *fwspec = (struct irq_fwspec *)arg;
 struct of_ioapic_type *it;
 struct irq_alloc_info tmp;
+ int type_index;
Â
- if (WARN_ON(irq_data->args_count < 2))
+ if (WARN_ON(fwspec->param_count < 2))
 return -EINVAL;
- if (irq_data->args[1] >= ARRAY_SIZE(of_ioapic_type))
+
+ type_index = fwspec->param[1];
+ if (type_index >= ARRAY_SIZE(of_ioapic_type))
 return -EINVAL;
Â
- it = &of_ioapic_type[irq_data->args[1]];
+ it = &of_ioapic_type[type_index];
 ioapic_set_alloc_attr(&tmp, NUMA_NO_NODE, it->trigger, it->polarity);
 tmp.ioapic_id = mpc_ioapic_id(mp_irqdomain_ioapic_idx(domain));
- tmp.ioapic_pin = irq_data->args[0];
+ tmp.ioapic_pin = fwspec->param[0];
Â
 return mp_irqdomain_alloc(domain, virq, nr_irqs, &tmp);
Â}
--Â
2.7.4