On Mon, 16 Jan 2017, Arvind Yadav wrote: Cc'ing the MIPS folks.
> Eliminating kernel panic due to NULL pointer dereferencing and > other failure in __gic_init. > Here, __gic_init can fail. This error check will avoid NULL pointer > dereference and kernel panic. > > Signed-off-by: Arvind Yadav <[email protected]> > --- > drivers/irqchip/irq-mips-gic.c | 40 +++++++++++++++++++++++++++++++--------- > 1 file changed, 31 insertions(+), 9 deletions(-) > > diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c > index c01c09e..bf0816f 100644 > --- a/drivers/irqchip/irq-mips-gic.c > +++ b/drivers/irqchip/irq-mips-gic.c > @@ -968,7 +968,7 @@ int gic_ipi_domain_match(struct irq_domain *d, struct > device_node *node, > .match = gic_ipi_domain_match, > }; > > -static void __init __gic_init(unsigned long gic_base_addr, > +static int __init __gic_init(unsigned long gic_base_addr, > unsigned long gic_addrspace_size, > unsigned int cpu_vec, unsigned int irqbase, > struct device_node *node) > @@ -979,6 +979,10 @@ static void __init __gic_init(unsigned long > gic_base_addr, > __gic_base_addr = gic_base_addr; > > gic_base = ioremap_nocache(gic_base_addr, gic_addrspace_size); > + if (!gic_base) { > + pr_err("Failed to map GIC memory"); > + return -ENOMEM; > + } > > gicconfig = gic_read(GIC_REG(SHARED, GIC_SH_CONFIG)); > gic_shared_intrs = (gicconfig & GIC_SH_CONFIG_NUMINTRS_MSK) >> > @@ -1035,23 +1039,29 @@ static void __init __gic_init(unsigned long > gic_base_addr, > gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS + > gic_shared_intrs, irqbase, > &gic_irq_domain_ops, NULL); > - if (!gic_irq_domain) > - panic("Failed to add GIC IRQ domain"); > + if (!gic_irq_domain) { > + pr_err("Failed to add GIC IRQ domain"); > + goto iounmap; > + } > gic_irq_domain->name = "mips-gic-irq"; > > gic_dev_domain = irq_domain_add_hierarchy(gic_irq_domain, 0, > GIC_NUM_LOCAL_INTRS + > gic_shared_intrs, > node, &gic_dev_domain_ops, > NULL); > - if (!gic_dev_domain) > - panic("Failed to add GIC DEV domain"); > + if (!gic_dev_domain) { > + pr_err("Failed to add GIC DEV domain"); > + goto iounmap; > + } > gic_dev_domain->name = "mips-gic-dev"; > > gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain, > IRQ_DOMAIN_FLAG_IPI_PER_CPU, > GIC_NUM_LOCAL_INTRS + > gic_shared_intrs, > node, &gic_ipi_domain_ops, > NULL); > - if (!gic_ipi_domain) > - panic("Failed to add GIC IPI domain"); > + if (!gic_ipi_domain) { > + pr_err("Failed to add GIC IPI domain"); > + goto iounmap; > + } > > gic_ipi_domain->name = "mips-gic-ipi"; > gic_ipi_domain->bus_token = DOMAIN_BUS_IPI; > @@ -1067,13 +1077,22 @@ static void __init __gic_init(unsigned long > gic_base_addr, > } > > gic_basic_init(); > + return 0; > +iounmap: > + iounmap(gic_base); > + return -ENOMEM; > } > > void __init gic_init(unsigned long gic_base_addr, > unsigned long gic_addrspace_size, > unsigned int cpu_vec, unsigned int irqbase) > { > - __gic_init(gic_base_addr, gic_addrspace_size, cpu_vec, irqbase, NULL); > + int ret; > + > + ret = __gic_init(gic_base_addr, gic_addrspace_size, cpu_vec, irqbase, > + NULL); > + if (ret) > + pr_err("Failed to initialize GIC"); > } > > static int __init gic_of_init(struct device_node *node, > @@ -1083,6 +1102,7 @@ static int __init gic_of_init(struct device_node *node, > unsigned int cpu_vec, i = 0, reserved = 0; > phys_addr_t gic_base; > size_t gic_len; > + int ret; > > /* Find the first available CPU vector. */ > while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors", > @@ -1119,7 +1139,9 @@ static int __init gic_of_init(struct device_node *node, > write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN_MSK); > gic_present = true; > > - __gic_init(gic_base, gic_len, cpu_vec, 0, node); > + ret = __gic_init(gic_base, gic_len, cpu_vec, 0, node); > + if (ret) > + return ret; > > return 0; > } > -- > 1.9.1 > >
