x86, ioapic: Throw BUG instead of NULL dereference

Instead of plain NULL deref we better throw error
message with a backtrace. Actually we need more
gracious error handling here. Meanwhile leave it
as is.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: yinghai@kernel.org
LKML-Reference: <20090801075435.769301745@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index ffd8fdfcbe4c..2a145d3a8375 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -503,6 +503,10 @@ static void add_pin_to_irq_node(struct irq_cfg *cfg, int node, int apic, int pin
         }
 
         entry = get_one_free_irq_2_pin(node);
+        if (!entry) {
+                printk(KERN_ERR "can not alloc irq_pin_list\n");
+                BUG_ON(1);
+        }
         entry->apic = apic;
         entry->pin = pin;