controller: Derive RAMP tunnel flag from the SB Chassis record.

Commit [1] propagated other_config:is-vtep from the SB Chassis to the
local tunnel Interface and read it back from there. That doesn't
survive an ovn-controller upgrade: tunnel_add() sets other_config only
when it creates a new interface, while the path that reuses an existing
tunnel compares just the interface type and options. After an upgrade
the tunnel ports already exist with unchanged options, so the flag is
never added to them and chassis_tunnel->is_ramp_tunnel stays false
until the tunnel happens to be recreated for some other reason. As a
result, ICMP "fragmentation needed" packets arriving from RAMP tunnels
kept being dropped on upgraded chassis.
Instead, look the chassis up in the SB database by the name encoded in
the tunnel id and read other_config:is-vtep directly from there.  This
doesn't depend on any locally stored state, so it works for tunnels
created by older versions as well.

[1] 3391e61
Fixes: 3391e61 ("controller: Skip frag-needed handling for VTEP ICMP packets.")
Signed-off-by: Alexandra Rukomoinikova <ARukomoinikova@k2.cloud>
Signed-off-by: Ales Musil <amusil@redhat.com>

Author: Sashhkaa

controller/encaps.c

@@ -43,7 +43,6 @@ encaps_register_ovs_idl(struct ovsdb_idl *ovs_idl)
     ovsdb_idl_track_add_column(ovs_idl, &ovsrec_interface_col_name);
     ovsdb_idl_track_add_column(ovs_idl, &ovsrec_interface_col_type);
     ovsdb_idl_track_add_column(ovs_idl, &ovsrec_interface_col_options);
-    ovsdb_idl_track_add_column(ovs_idl, &ovsrec_interface_col_other_config);
 }
 
 /* Enough context to create a new tunnel, using tunnel_add(). */
@@ -208,7 +207,6 @@ tunnel_add(struct tunnel_ctx *tc,
            const struct ovsrec_open_vswitch_table *ovs_table)
 {
     struct smap options = SMAP_INITIALIZER(&options);
-    struct smap other_config = SMAP_INITIALIZER(&other_config);
     smap_add(&options, "remote_ip", encap->ip);
     smap_add(&options, "local_ip", local_ip);
     smap_add(&options, "key", "flow");
@@ -286,11 +284,6 @@ tunnel_add(struct tunnel_ctx *tc,
         }
     }
 
-    if (is_ramp_tunnel(&chassis_rec->other_config)) {
-        /* Propagate ramp switch flag from chassis to interface. */
-        smap_add(&other_config, "is-vtep", "true");
-    }
-
     /* If there's an existing tunnel record that does not need any change,
      * keep it.  Otherwise, create a new record (if there was an existing
      * record, the new record will supplant it and encaps_run() will delete
@@ -338,7 +331,6 @@ tunnel_add(struct tunnel_ctx *tc,
     ovsrec_interface_set_name(iface, port_name);
     ovsrec_interface_set_type(iface, encap->type);
     ovsrec_interface_set_options(iface, &options);
-    ovsrec_interface_set_other_config(iface, &other_config);
 
     struct ovsrec_port *port = ovsrec_port_insert(tc->ovs_txn);
     ovsrec_port_set_name(port, port_name);
@@ -354,7 +346,6 @@ tunnel_add(struct tunnel_ctx *tc,
     free(tunnel_entry_id);
     free(tunnel_entry_id_old);
     smap_destroy(&options);
-    smap_destroy(&other_config);
 }
 
 static bool

controller/local_data.c

@@ -30,6 +30,7 @@
 #include "lport.h"
 #include "lib/ovn-util.h"
 #include "lib/ovn-sb-idl.h"
+#include "lib/chassis-index.h"
 #include "local_data.h"
 #include "lport.h"
 
@@ -457,6 +458,7 @@ tracked_datapaths_destroy(struct hmap *tracked_datapaths)
 void
 local_nonvif_data_run(const struct ovsrec_bridge *br_int,
                       const struct sbrec_chassis *chassis_rec,
+                      struct ovsdb_idl_index *sbrec_chassis_by_name,
                       struct simap *patch_ofports,
                       struct hmap *chassis_tunnels,
                       struct flow_based_tunnel *flow_tunnels)
@@ -525,15 +527,17 @@ local_nonvif_data_run(const struct ovsrec_bridge *br_int,
                 if (!encaps_tunnel_id_parse(tunnel_id, &hash_id, &ip, NULL)) {
                     continue;
                 }
+                const struct sbrec_chassis *chassis =
+                    chassis_lookup_by_name(sbrec_chassis_by_name, hash_id);
                 struct chassis_tunnel *tun = xmalloc(sizeof *tun);
                 hmap_insert(chassis_tunnels, &tun->hmap_node,
                             hash_string(hash_id, 0));
                 tun->chassis_id = xstrdup(tunnel_id);
                 tun->ofport = u16_to_ofp(ofport);
                 tun->type = tunnel_type;
                 tun->is_ipv6 = ip ? addr_is_ipv6(ip) : false;
-                tun->is_ramp_tunnel = is_ramp_tunnel(&iface_rec->other_config);
-
+                tun->is_ramp_tunnel =
+                    chassis ? is_ramp_tunnel(&chassis->other_config) : false;
                 free(hash_id);
                 free(ip);
                 break;

controller/local_data.h

@@ -161,6 +161,7 @@ struct flow_based_tunnel {
 
 void local_nonvif_data_run(const struct ovsrec_bridge *br_int,
                            const struct sbrec_chassis *chassis,
+                           struct ovsdb_idl_index *sbrec_chassis_by_name,
                            struct simap *patch_ofports,
                            struct hmap *chassis_tunnels,
                            struct flow_based_tunnel *flow_tunnels);

controller/ovn-controller.c

@@ -3730,7 +3730,7 @@ en_non_vif_data_run(struct engine_node *node, void *data)
     ed_non_vif_data->use_flow_based_tunnels =
         is_flow_based_tunnels_enabled(ovs_table, chassis);
 
-    local_nonvif_data_run(br_int, chassis,
+    local_nonvif_data_run(br_int, chassis, sbrec_chassis_by_name,
                           &ed_non_vif_data->patch_ofports,
                           &ed_non_vif_data->chassis_tunnels,
                           ed_non_vif_data->flow_tunnels);