1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 69906cacd04f..a17f11850669 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -1312,6 +1312,7 @@ static int
 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
                         struct vhost_scsi_target *t)
 {
+        struct se_portal_group *se_tpg;
         struct tcm_vhost_tport *tv_tport;
         struct tcm_vhost_tpg *tpg;
         struct tcm_vhost_tpg **vs_tpg;
@@ -1359,6 +1360,21 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs,
                                 ret = -EEXIST;
                                 goto out;
                         }
+                        /*
+                         * In order to ensure individual vhost-scsi configfs
+                         * groups cannot be removed while in use by vhost ioctl,
+                         * go ahead and take an explicit se_tpg->tpg_group.cg_item
+                         * dependency now.
+                         */
+                        se_tpg = &tpg->se_tpg;
+                        ret = configfs_depend_item(se_tpg->se_tpg_tfo->tf_subsys,
+                                                   &se_tpg->tpg_group.cg_item);
+                        if (ret) {
+                                pr_warn("configfs_depend_item() failed: %d\n", ret);
+                                kfree(vs_tpg);
+                                mutex_unlock(&tpg->tv_tpg_mutex);
+                                goto out;
+                        }
                         tpg->tv_tpg_vhost_count++;
                         tpg->vhost_scsi = vs;
                         vs_tpg[tpg->tport_tpgt] = tpg;
@@ -1401,6 +1417,7 @@ static int
 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
                           struct vhost_scsi_target *t)
 {
+        struct se_portal_group *se_tpg;
         struct tcm_vhost_tport *tv_tport;
         struct tcm_vhost_tpg *tpg;
         struct vhost_virtqueue *vq;
@@ -1449,6 +1466,13 @@ vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
                 vs->vs_tpg[target] = NULL;
                 match = true;
                 mutex_unlock(&tpg->tv_tpg_mutex);
+                /*
+                 * Release se_tpg->tpg_group.cg_item configfs dependency now
+                 * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
+                 */
+                se_tpg = &tpg->se_tpg;
+                configfs_undepend_item(se_tpg->se_tpg_tfo->tf_subsys,
+                                       &se_tpg->tpg_group.cg_item);
         }
         if (match) {
                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {