ARM: davinci: Check for NULL return from irq_alloc_generic_chip

Avoid NULL dereference of irq_alloc_generic_chip return in low
memory conditions.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

diff --git a/arch/arm/mach-davinci/irq.c b/arch/arm/mach-davinci/irq.c
index bfe68ec..85e77fd 100644 (file)
--- a/arch/arm/mach-davinci/irq.c
+++ b/arch/arm/mach-davinci/irq.c
@@ -52,6 +52,12 @@ davinci_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
        struct irq_chip_type *ct;
 
        gc = irq_alloc_generic_chip("AINTC", 1, irq_start, base, handle_edge_irq);
+       if (!gc) {
+               pr_err("%s: irq_alloc_generic_chip for IRQ %u failed\n",
+                      __func__, irq_start);
+               return;
+       }
+
        ct = gc->chip_types;
        ct->chip.irq_ack = irq_gc_ack;
        ct->chip.irq_mask = irq_gc_mask_clr_bit;