[patch 1/1] Do not unregister_cpu_notifier in case of wrong state

[Heinz Graalfs <graalfs@linux.vnet.ibm.com>]

[-- Attachment #1: hwsampler-shutdown.patch --]
[-- Type: text/plain, Size: 823 bytes --]

From: Heinz Graalfs <graalfs@linux.vnet.ibm.com>

This patch avoids calling unregister_cpu_notifier() in case
hwsampler_shutdown() is invoked in wrong state. 
---
 arch/s390/oprofile/hwsampler.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Index: 2.6.39/arch/s390/oprofile/hwsampler.c
===================================================================
--- 2.6.39.orig/arch/s390/oprofile/hwsampler.c
+++ 2.6.39/arch/s390/oprofile/hwsampler.c
@@ -1143,11 +1143,14 @@ int hwsampler_shutdown()
 
 		unregister_external_interrupt(0x1407, hws_ext_handler);
 		hws_state = HWS_INIT;
+
+		mutex_unlock(&hws_sem);
+		unregister_cpu_notifier(&hws_cpu_notifier);
+
 		rc = 0;
+	} else {
+		mutex_unlock(&hws_sem);
 	}
-	mutex_unlock(&hws_sem);
-
-	unregister_cpu_notifier(&hws_cpu_notifier);
 
 	return rc;
 }