On Mon, Oct 30, 2023 at 9:46 AM Xavier Simonart <xsimo...@redhat.com> wrote:
> When a tunnel_key for a datapath was changed, the local_datapaths hmap was
> not properly updated
> as the old/initial entry was not removed.
> - If the datapath was not deleted at the same time, a new entry (for the
> same dp) was created
> in the local_datapaths as the previous entry was not found (wrong hash).
> - If the datapath was deleted at the same time, the former entry also
> remained (as, again, the hash
> was wrong). So, we kept a deleted (dp) entry in the hmap, and might
> crash when we used it later.
>
> When tunnel_key is updated for an existing datapath, we now clean the
> local_datapaths,
> removing bad entries (i.e entries for which the hash is not the
> tunnel_key).
>
> This issue was identified by flaky failures of test "ovn-ic -- route
> deletion upon TS deletion".
>
> Backtrace:
> 0 0x0000000000504a9a in hmap_first_with_hash (hmap=0x20f4d90,
> hmap@entry=0x5d5634,
> hmap=0x20f4d90, hmap@entry=0x5d5634, hash=1956414673) at
> ./include/openvswitch/hmap.h:360
> 1 smap_find__ (smap=smap@entry=0x20f4d90, key=key@entry=0x5d5634
> "snat-ct-zone", key_len=key_len@entry=12, hash=1956414673) at
> lib/smap.c:421
> 2 0x0000000000505073 in smap_get_node (key=0x5d5634 "snat-ct-zone",
> smap=0x20f4d90) at lib/smap.c:217
> 3 smap_get_def (def=0x0, key=0x5d5634 "snat-ct-zone", smap=0x20f4d90) at
> lib/smap.c:208
> 4 smap_get (smap=0x20f4d90, key=key@entry=0x5d5634 "snat-ct-zone") at
> lib/smap.c:200
> 5 0x0000000000419898 in get_common_nat_zone (ldp=0x20a8c40,
> ldp=0x20a8c40) at controller/lflow.c:831
> 6 add_matches_to_flow_table (lflow=lflow@entry=0x21ddf90,
> ldp=ldp@entry=0x20a8c40,
> matches=matches@entry=0x211bb50, ptable=ptable@entry=10 '\n',
> output_ptable=output_ptable@entry=37 '%', ovnacts=ovnacts@entry
> =0x7ffd19b99de0,
> ingress=true, l_ctx_in=0x7ffd19b9a300, l_ctx_out=0x7ffd19b9a2c0) at
> controller/lflow.c:892
> 7 0x000000000041a29b in consider_logical_flow__ (lflow=lflow@entry=0x21ddf90,
> dp=0x20eb720, l_ctx_in=l_ctx_in@entry=0x7ffd19b9a300,
> l_ctx_out=l_ctx_out@entry=0x7ffd19b9a2c0) at controller/lflow.c:1207
> 8 0x000000000041a587 in consider_logical_flow (lflow=lflow@entry=0x21ddf90,
> is_recompute=is_recompute@entry=false, l_ctx_in=l_ctx_in@entry=0x7ffd19b9a300,
> l_ctx_out=l_ctx_out@entry=0x7ffd19b9a2c0) at controller/lflow.c:1276
> 9 0x000000000041e30f in lflow_handle_changed_flows
> (l_ctx_in=l_ctx_in@entry=0x7ffd19b9a300,
> l_ctx_out=l_ctx_out@entry=0x7ffd19b9a2c0)
> at controller/lflow.c:271
> 10 0x0000000000439fc7 in lflow_output_sb_logical_flow_handler
> (node=0x7ffd19ba5b70, data=<optimized out>) at
> controller/ovn-controller.c:4045
> 11 0x00000000004682fe in engine_compute (recompute_allowed=<optimized
> out>, node=<optimized out>) at lib/inc-proc-eng.c:441
> 12 engine_run_node (recompute_allowed=true, node=0x7ffd19ba5b70) at
> lib/inc-proc-eng.c:503
> 13 engine_run (recompute_allowed=recompute_allowed@entry=true) at
> lib/inc-proc-eng.c:528
> 14 0x000000000040ade2 in main (argc=<optimized out>, argv=<optimized out>)
> at controller/ovn-controller.c:5709
>
> Signed-off-by: Xavier Simonart <xsimo...@redhat.com>
>
> ---
> v2: Fixed potential memory leak.
> ---
> controller/local_data.c | 14 +++++++++++++
> controller/local_data.h | 4 ++++
> controller/ovn-controller.c | 22 +++++++++++++++++++
> tests/ovn.at | 42 +++++++++++++++++++++++++++++++++++++
> 4 files changed, 82 insertions(+)
>
> diff --git a/controller/local_data.c b/controller/local_data.c
> index 3a7d3afeb..8f0890a14 100644
> --- a/controller/local_data.c
> +++ b/controller/local_data.c
> @@ -56,6 +56,20 @@ static bool datapath_is_transit_switch(const struct
> sbrec_datapath_binding *);
>
> static uint64_t local_datapath_usage;
>
> +/* To be used when hmap_node.hash might be wrong e.g. tunnel_key got
> updated */
> +struct local_datapath *
> +get_local_datapath_no_hash(const struct hmap *local_datapaths,
> + uint32_t tunnel_key)
> +{
> + struct local_datapath *ld;
> + HMAP_FOR_EACH (ld, hmap_node, local_datapaths) {
> + if (ld->datapath->tunnel_key == tunnel_key) {
> + return ld;
> + }
> + }
> + return NULL;
> +}
> +
> struct local_datapath *
> get_local_datapath(const struct hmap *local_datapaths, uint32_t
> tunnel_key)
> {
> diff --git a/controller/local_data.h b/controller/local_data.h
> index f6d8f725f..a1bf0790b 100644
> --- a/controller/local_data.h
> +++ b/controller/local_data.h
> @@ -69,6 +69,10 @@ struct local_datapath *local_datapath_alloc(
> const struct sbrec_datapath_binding *);
> struct local_datapath *get_local_datapath(const struct hmap *,
> uint32_t tunnel_key);
> +struct local_datapath
> +*get_local_datapath_no_hash(const struct hmap *local_datapaths,
> + uint32_t tunnel_key);
> +
> bool
> need_add_peer_to_local(
> struct ovsdb_idl_index *sbrec_port_binding_by_name,
> diff --git a/controller/ovn-controller.c b/controller/ovn-controller.c
> index da7d145ed..ca8e383d8 100644
> --- a/controller/ovn-controller.c
> +++ b/controller/ovn-controller.c
> @@ -1902,6 +1902,7 @@ runtime_data_sb_datapath_binding_handler(struct
> engine_node *node OVS_UNUSED,
> engine_get_input("SB_datapath_binding", node));
> const struct sbrec_datapath_binding *dp;
> struct ed_type_runtime_data *rt_data = data;
> + struct local_datapath *ld;
>
> SBREC_DATAPATH_BINDING_TABLE_FOR_EACH_TRACKED (dp, dp_table) {
> if (sbrec_datapath_binding_is_deleted(dp)) {
> @@ -1909,6 +1910,27 @@ runtime_data_sb_datapath_binding_handler(struct
> engine_node *node OVS_UNUSED,
> dp->tunnel_key)) {
> return false;
> }
> + /* If the tunnel key got updated, get_local_datapath will not
> find
> + * the ld. Use get_local_datapath_no_hash which does not
> + * rely on the hash.
> + */
> + if (sbrec_datapath_binding_is_updated(dp,
> + SBREC_DATAPATH_BINDING_COL_TUNNEL_KEY)) {
> + if (get_local_datapath_no_hash(&rt_data->local_datapaths,
> + dp->tunnel_key)) {
> + return false;
> + }
> + }
> + } else if (sbrec_datapath_binding_is_updated(dp,
> + SBREC_DATAPATH_BINDING_COL_TUNNEL_KEY) &&
> + !sbrec_datapath_binding_is_new(dp)) {
> + /* If the tunnel key is updated, remove the entry (with a
> wrong
> + * hash) from the map. It will be (properly) added back later.
> + */
> + if ((ld =
> get_local_datapath_no_hash(&rt_data->local_datapaths,
> + dp->tunnel_key))) {
> + hmap_remove(&rt_data->local_datapaths, &ld->hmap_node);
> + }
> }
> }
>
> diff --git a/tests/ovn.at b/tests/ovn.at
> index 637d92bed..aba08856b 100644
> --- a/tests/ovn.at
> +++ b/tests/ovn.at
> @@ -36957,3 +36957,45 @@ AT_CHECK([grep -c "NXT_CT_FLUSH_ZONE"
> hv1/ovs-vswitchd.log], [0], [dnl
> OVN_CLEANUP([hv1])
> AT_CLEANUP
> ])
> +
> +OVN_FOR_EACH_NORTHD([
> +AT_SETUP([Delete ls after changing tunnel_key])
> +ovn_start
> +
> +net_add n1
> +
> +sim_add hv1
> +as hv1
> +check ovs-vsctl add-br br-phys
> +ovn_attach n1 br-phys 192.168.0.11
> +
> +check ovn-nbctl --wait=hv ls-add ls \
> + -- lsp-add ls lsp1 \
> + -- lsp-add ls ls-lr \
> + -- lr-add lr \
> + -- lrp-add lr lr-ls f0:00:00:00:00:f1 192.168.1.1/24 \
> + -- set Logical_Switch_Port ls-lr \
> + type=router \
> + options:router-port=lr-ls \
> + addresses=router \
> + -- lrp-set-gateway-chassis lr-ls hv1
> +
> +sleep_controller hv1
> +
> +check ovn-nbctl --wait=sb set Logical_Switch ls
> other_config:requested-tnl-key=1000
> +check ovn-nbctl --wait=sb ls-del ls
> +wake_up_controller hv1
> +
> +check ovn-nbctl --wait=hv sync
> +
> +check ovn-nbctl --wait=hv ls-add ls1 \
> + -- lsp-add ls1 ls1-lr \
> + -- lrp-add lr lr-ls1 f0:00:00:00:00:f2 192.168.2.1/24 \
> + -- set Logical_Switch_Port ls1-lr type=router
> options:router-port=lr-ls1 addresses=router \
> + -- lrp-set-gateway-chassis lr-ls1 hv1
> +
> +OVN_CLEANUP([hv1])
> +
> +AT_CLEANUP
> +])
> +
> --
> 2.31.1
>
> _______________________________________________
> dev mailing list
> d...@openvswitch.org
> https://mail.openvswitch.org/mailman/listinfo/ovs-dev
>
>
Looks good to me, thanks.
Acked-by: Ales Musil <amu...@redhat.com>
--
Ales Musil
Senior Software Engineer - OVN Core
Red Hat EMEA <https://www.redhat.com>
amu...@redhat.com
<https://red.ht/sig>
_______________________________________________
dev mailing list
d...@openvswitch.org
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
