LU-8637 obdclass: LWP callback hold export reference

[fs/lustre-release.git] / lustre / obdclass / obd_mount_server.c

diff --git a/lustre/obdclass/obd_mount_server.c b/lustre/obdclass/obd_mount_server.c
index 55a9306..cf30df6 100644 (file)
--- a/lustre/obdclass/obd_mount_server.c
+++ b/lustre/obdclass/obd_mount_server.c
@@ -407,6 +407,7 @@ int lustre_register_lwp_item(const char *lwpname, struct obd_export **exp,
 {
        struct obd_device        *lwp;
        struct lwp_register_item *lri;
+       bool cb = false;
        ENTRY;
 
        LASSERTF(strlen(lwpname) < MTI_NAME_MAXLEN, "lwpname is too long %s\n",
@@ -445,9 +446,11 @@ int lustre_register_lwp_item(const char *lwpname, struct obd_export **exp,
 
        spin_lock(&lwp_register_list_lock);
        list_add(&lri->lri_list, &lwp_register_list);
+       if (*exp != NULL)
+               cb = true;
        spin_unlock(&lwp_register_list_lock);
 
-       if (*exp != NULL && cb_func != NULL)
+       if (cb && cb_func != NULL)
                cb_func(cb_data);
        lustre_put_lwp_item(lri);
 
@@ -527,11 +530,12 @@ again:
                if (*lri->lri_exp != NULL)
                        continue;
                *lri->lri_exp = class_export_get(exp);
+               if (lri->lri_cb_func == NULL)
+                       continue;
                atomic_inc(&lri->lri_ref);
                spin_unlock(&lwp_register_list_lock);
 
-               if (lri->lri_cb_func != NULL)
-                       lri->lri_cb_func(lri->lri_cb_data);
+               lri->lri_cb_func(lri->lri_cb_data);
                lustre_put_lwp_item(lri);
 
                /* Others may have changed the list after we unlock, we have