From: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Date: Thu, 13 Jan 2011 21:43:06 +0000 (-0500)
Subject: Fix ltt-relay-alloc NULL pointer exception
X-Git-Tag: v0.19.6~1
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=031e36b31fc9aa1ca6dcaa35091bffa3b4b59555;p=lttng-modules.git

Fix ltt-relay-alloc NULL pointer exception

repetitive load/unload of ltt-relay-alloc caused null pointer exception because
the cpu hotplug was never unregistered upon exit.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/ltt-relay-alloc.c b/ltt-relay-alloc.c
index 6ff552ef..43246a73 100644
--- a/ltt-relay-alloc.c
+++ b/ltt-relay-alloc.c
@@ -716,9 +716,14 @@ void *ltt_relay_offset_address(struct ltt_chanbuf_alloc *bufa, size_t offset)
 }
 EXPORT_SYMBOL_GPL(ltt_relay_offset_address);
 
+static struct notifier_block ltt_relay_hotcpu = {
+	.notifier_call = ltt_relay_hotcpu_callback,
+	.priority = 5,
+};
+
 static __init int ltt_relay_alloc_init(void)
 {
-	hotcpu_notifier(ltt_relay_hotcpu_callback, 5);
+	register_cpu_notifier(&ltt_relay_hotcpu);
 	ltt_relay_init();
 	ltt_ascii_init();
 	return 0;
@@ -728,6 +733,7 @@ static void __exit ltt_relay_alloc_exit(void)
 {
 	ltt_ascii_exit();
 	ltt_relay_exit();
+	unregister_cpu_notifier(&ltt_relay_hotcpu);
 }
 
 module_init(ltt_relay_alloc_init);