genirq: Fix memory leak when calling irq_free_hwirqs()

irq_free_hwirqs() always calls irq_free_descs() with a cnt == 0
which makes it a no-op since the interrupt count to free is
decremented in itself.

Fixes: 7b6ef1262549f6afc5c881aaef80beb8fd15f908

Signed-off-by: Keith Busch <keith.busch@intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1404167084-8070-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 7339e42a85ab9bb7f425a4da7806a0a37d9ec36c..1487a123db5c82887c9dfd3c49833e48004e99a8 100644 (file)
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -455,9 +455,9 @@ EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
  */
 void irq_free_hwirqs(unsigned int from, int cnt)
 {
-       int i;
+       int i, j;
 
-       for (i = from; cnt > 0; i++, cnt--) {
+       for (i = from, j = cnt; j > 0; i++, j--) {
                irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
                arch_teardown_hwirq(i);
        }