drbd: Allow online change of replication protocol only with agreed_pv >= 100
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 40de384..d4b29fd6 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1671,6 +1671,11 @@
struct drbd_conf *mdev;
int i;
+ if (tconn->net_conf && tconn->agreed_pro_version < 100 &&
+ tconn->cstate == C_WF_REPORT_PARAMS &&
+ new_conf->wire_protocol != tconn->net_conf->wire_protocol)
+ return ERR_NEED_APV_100;
+
if (new_conf->two_primaries &&
(new_conf->wire_protocol != DRBD_PROT_C))
return ERR_NOT_PROTO_C;