[S390] cio: css_register_subchannel race.

Asynchronous probe can release memory of a subchannel before
css_get_ssd_info is called. To fix this call css_get_ssd_info
before registering with driver core.
Signed-off-by: NStefan Bader <shbader@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/css.c

@@ -139,6 +139,8 @@ css_register_subchannel(struct subchannel *sch)
 	sch->dev.release = &css_subchannel_release;
 	sch->dev.groups = subch_attr_groups;
 
+	css_get_ssd_info(sch);
+
 	/* make it known to the system */
 	ret = css_sch_device_register(sch);
 	if (ret) {
@@ -146,7 +148,6 @@ css_register_subchannel(struct subchannel *sch)
 			__func__, sch->dev.bus_id);
 		return ret;
 	}
-	css_get_ssd_info(sch);
 	return ret;
 }