scsi: core: Make sure that hosts outlive targets

[sfrench/cifs-2.6.git] / drivers / scsi / hosts.c

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index ef6c0e37accefcd185ece90fa6dced559ad8450b..8fa98c8d0ee0937deee2788303ff8b83fa30016c 100644 (file)
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -190,6 +190,13 @@ void scsi_remove_host(struct Scsi_Host *shost)
        transport_unregister_device(&shost->shost_gendev);
        device_unregister(&shost->shost_dev);
        device_del(&shost->shost_gendev);
+
+       /*
+        * After scsi_remove_host() has returned the scsi LLD module can be
+        * unloaded and/or the host resources can be released. Hence wait until
+        * the dependent SCSI targets and devices are gone before returning.
+        */
+       wait_event(shost->targets_wq, atomic_read(&shost->target_count) == 0);
 }
 EXPORT_SYMBOL(scsi_remove_host);
 
@@ -394,6 +401,7 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
        INIT_LIST_HEAD(&shost->starved_list);
        init_waitqueue_head(&shost->host_wait);
        mutex_init(&shost->scan_mutex);
+       init_waitqueue_head(&shost->targets_wq);
 
        index = ida_alloc(&host_index_ida, GFP_KERNEL);
        if (index < 0) {