Merge branch 'linus' into x86/urgent

[pandora-kernel.git] / drivers / s390 / char / sclp_config.c

diff --git a/drivers/s390/char/sclp_config.c b/drivers/s390/char/sclp_config.c
index ad05a87..fff4ff4 100644 (file)
--- a/drivers/s390/char/sclp_config.c
+++ b/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)
@@ -74,10 +85,8 @@ static int __init sclp_conf_init(void)
        INIT_WORK(&sclp_cpu_change_work, sclp_cpu_change_notify);
 
        rc = sclp_register(&sclp_conf_register);
-       if (rc) {
-               printk(KERN_ERR TAG "failed to register (%d).\n", rc);
+       if (rc)
                return rc;
-       }
 
        if (!(sclp_conf_register.sclp_send_mask & EVTYP_CONFMGMDATA_MASK)) {
                printk(KERN_WARNING TAG "no configuration management.\n");