From c0048de29d207fe3407360c28a9025891506dd6a Mon Sep 17 00:00:00 2001
From: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Date: Wed, 6 Feb 2013 16:12:03 +0100
Subject: [PATCH] iucv: fix kernel panic at reboot
The iucv base layer is initialized during the registration of the
first iucv handler. If no handler is registered and the
iucv_reboot_event() notifier is called, a missing check can cause
a kernel panic in iucv_block_cpu(). To solve this issue, check the
IRQ masks invoke iucv_block_cpu() for enabled CPUs only.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
net/iucv/iucv.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/iucv/iucv.c b/net/iucv/iucv.c
index df082508362d..4fe76ff214c2 100644
--- a/net/iucv/iucv.c
+++ b/net/iucv/iucv.c
@@ -831,8 +831,11 @@ static int iucv_reboot_event(struct notifier_block *this,
{
int i;
+ if (cpumask_empty(&iucv_irq_cpumask))
+ return NOTIFY_DONE;
+
get_online_cpus();
- on_each_cpu(iucv_block_cpu, NULL, 1);
+ on_each_cpu_mask(&iucv_irq_cpumask, iucv_block_cpu, NULL, 1);
preempt_disable();
for (i = 0; i < iucv_max_pathid; i++) {
if (iucv_path_table[i])