From 805735e21040cc2904ad68f4827f4aa2f644a6f1 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 14 Jul 2008 09:57:28 +0200
Subject: [PATCH] --- yaml --- r: 98949 b: refs/heads/master c:
 b9732ca1cb2c18129d2f984b8de02db141b7b830 h: refs/heads/master i:   98947:
 b34ee5c02e1ff06c3e584e505beb74866cf3eb9a v: v3

---
 [refs]                                |  2 +-
 trunk/drivers/s390/char/sclp_config.c | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 160b9c63d97b..a561a2d82d5b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0c3252d58c54c87ee0f8f40d840e0146a3b1d5fd
+refs/heads/master: b9732ca1cb2c18129d2f984b8de02db141b7b830
diff --git a/trunk/drivers/s390/char/sclp_config.c b/trunk/drivers/s390/char/sclp_config.c
index ad05a87bc480..7c9b39cee595 100644
--- a/trunk/drivers/s390/char/sclp_config.c
+++ b/trunk/drivers/s390/char/sclp_config.c
@@ -8,6 +8,7 @@
 #include <linux/init.h>
 #include <linux/errno.h>
 #include <linux/cpu.h>
+#include <linux/kthread.h>
 #include <linux/sysdev.h>
 #include <linux/workqueue.h>
 #include <asm/smp.h>
@@ -40,9 +41,19 @@ static void sclp_cpu_capability_notify(struct work_struct *work)
 	put_online_cpus();
 }
 
-static void __ref sclp_cpu_change_notify(struct work_struct *work)
+static int sclp_cpu_kthread(void *data)
 {
 	smp_rescan_cpus();
+	return 0;
+}
+
+static void __ref sclp_cpu_change_notify(struct work_struct *work)
+{
+	/* Can't call smp_rescan_cpus() from  workqueue context since it may
+	 * deadlock in case of cpu hotplug. So we have to create a kernel
+	 * thread in order to call it.
+	 */
+	kthread_run(sclp_cpu_kthread, NULL, "cpu_rescan");
 }
 
 static void sclp_conf_receiver_fn(struct evbuf_header *evbuf)