irq: fix irqpoll && sparseirq
Steven Noonan reported a boot hang when using irqpoll and
CONFIG_HAVE_SPARSE_IRQ=y.
The irqpoll loop needs to be updated to not iterate from 1 to nr_irqs
but to iterate via for_each_irq_desc(). (in the former case desc can
be NULL which crashes the box)
Reported-by: Steven Noonan <steven@uplinklabs.net>
Tested-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index b5d9060..ec5a4be 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -90,14 +90,15 @@
{
int i;
int ok = 0;
+ struct irq_desc *desc;
- for (i = 1; i < nr_irqs; i++) {
- struct irq_desc *desc;
+ for_each_irq_desc(i, desc) {
+ if (!i)
+ continue;
if (i == irq) /* Already tried */
continue;
- desc = irq_to_desc(i);
if (try_one_irq(i, desc))
ok = 1;
}
@@ -108,10 +109,14 @@
static void poll_spurious_irqs(unsigned long dummy)
{
int i;
- for (i = 1; i < nr_irqs; i++) {
- struct irq_desc *desc = irq_to_desc(i);
+ struct irq_desc *desc;
+
+ for_each_irq_desc(i, desc) {
unsigned int status;
+ if (!i)
+ continue;
+
/* Racy but it doesn't matter */
status = desc->status;
barrier();
@@ -278,7 +283,7 @@
__setup("irqfixup", irqfixup_setup);
module_param(irqfixup, int, 0644);
-MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode 2: irqpoll mode");
+MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode, 2: irqpoll mode");
static int __init irqpoll_setup(char *str)
{