drbd: re-add lost conf_mutex protection in drbd_set_role
The conf_update mutex used to be held while clearing the
net_conf->discard_my_data flag inside drbd_set_role.
It was moved into drbd_adm_set_role with
drbd: allow parallel promote/demote actions
but then replaced at that location by the newly introduced adm_mutex with
drbd: Fix a potential deadlock in drbdsetup, introduce resource->adm_mutex
And I simply forgot to put it back in at the original location.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 133e9b3..23670d8 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -661,11 +661,11 @@
put_ldev(device);
}
} else {
- /* Called from drbd_adm_set_role only.
- * We are still holding the conf_update mutex. */
+ mutex_lock(&device->resource->conf_update);
nc = connection->net_conf;
if (nc)
nc->discard_my_data = 0; /* without copy; single bit op is atomic */
+ mutex_unlock(&device->resource->conf_update);
set_disk_ro(device->vdisk, false);
if (get_ldev(device)) {