3 files changed, 19 insertions, 2 deletions
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
index d329f8b12e2b..2aeaf5c31ae5 100644
--- a/drivers/scsi/scsi_pm.c
+++ b/drivers/scsi/scsi_pm.c
@@ -7,6 +7,7 @@
 
 #include <linux/pm_runtime.h>
 #include <linux/export.h>
+#include <linux/async.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_device.h>
@@ -69,6 +70,19 @@ static int scsi_bus_resume_common(struct device *dev)
 	return err;
 }
 
+static int scsi_bus_prepare(struct device *dev)
+{
+	if (scsi_is_sdev_device(dev)) {
+		/* sd probing uses async_schedule.  Wait until it finishes. */
+		async_synchronize_full();
+
+	} else if (scsi_is_host_device(dev)) {
+		/* Wait until async scanning is finished */
+		scsi_complete_async_scans();
+	}
+	return 0;
+}
+
 static int scsi_bus_suspend(struct device *dev)
 {
 	return scsi_bus_suspend_common(dev, PMSG_SUSPEND);
@@ -87,6 +101,7 @@ static int scsi_bus_poweroff(struct device *dev)
 #else /* CONFIG_PM_SLEEP */
 
 #define scsi_bus_resume_common		NULL
+#define scsi_bus_prepare		NULL
 #define scsi_bus_suspend		NULL
 #define scsi_bus_freeze			NULL
 #define scsi_bus_poweroff		NULL
@@ -195,6 +210,7 @@ void scsi_autopm_put_host(struct Scsi_Host *shost)
 #endif /* CONFIG_PM_RUNTIME */
 
 const struct dev_pm_ops scsi_bus_pm_ops = {
+	.prepare =		scsi_bus_prepare,
 	.suspend =		scsi_bus_suspend,
 	.resume =		scsi_bus_resume_common,
 	.freeze =		scsi_bus_freeze,
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 2a588955423a..5b475d0832cb 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -110,6 +110,7 @@ extern void scsi_exit_procfs(void);
 #endif /* CONFIG_PROC_FS */
 
 /* scsi_scan.c */
+extern int scsi_complete_async_scans(void);
 extern int scsi_scan_host_selected(struct Scsi_Host *, unsigned int,
 				   unsigned int, unsigned int, int);
 extern void scsi_forget_host(struct Scsi_Host *);
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index b3c6d957fbd8..6e7ea4a2b7a1 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1815,6 +1815,7 @@ static void scsi_finish_async_scan(struct async_scan_data *data)
 	}
 	spin_unlock(&async_scan_lock);
 
+	scsi_autopm_put_host(shost);
 	scsi_host_put(shost);
 	kfree(data);
 }
@@ -1841,7 +1842,6 @@ static int do_scan_async(void *_data)
 
 	do_scsi_scan_host(shost);
 	scsi_finish_async_scan(data);
-	scsi_autopm_put_host(shost);
 	return 0;
 }
 
@@ -1869,7 +1869,7 @@ void scsi_scan_host(struct Scsi_Host *shost)
 	p = kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);
 	if (IS_ERR(p))
 		do_scan_async(data);
-	/* scsi_autopm_put_host(shost) is called in do_scan_async() */
+	/* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
 }
 EXPORT_SYMBOL(scsi_scan_host);