On Fri, Mar 6, 2026 at 10:46 AM Mark Michelson <[email protected]> wrote: > > On Fri, Mar 6, 2026 at 10:37 AM Rukomoinikova Aleksandra > <[email protected]> wrote: > > > > On 06.03.2026 18:21, Mark Michelson wrote: > > > On Fri, Mar 6, 2026 at 4:51 AM Ales Musil <[email protected]> wrote: > > >> > > >> > > >> On Thu, Mar 5, 2026 at 6:44 PM Mark Michelson via dev > > >> <[email protected]> wrote: > > >>> Hi Alexandra, thanks for the patch! > > >>> > > >>> I have a couple of small notes below. They're so minor, that I think > > >>> that a maintainer can fix them when merging, so there is no need for a > > >>> v4. > > >>> > > >>> Acked-by: Mark Michelson <[email protected]> > > >>> > > >>> On Mon, Mar 2, 2026 at 7:35 AM Alexandra Rukomoinikova > > >>> <[email protected]> wrote: > > >>>> The learned routes hash previously only used route parameters (prefix, > > >>>> nexthop, origin, route_table). This caused collisions when identical > > >>>> routes were learned through different transit switches, leading to > > >>>> infinite route re-learning. > > >>>> > > >>>> While such configurations are invalid due to overlapping IP addressing > > >>>> - ICshould handle them without looping. > > >>>> > > >>>> Fix by including the IC route UUID in the hash to distinguish routes > > >>>> with identical parameters but different origins. As a result, routers > > >>>> will now learn the correct number of prefixes as ECMP routes, making > > >>>> the misconfiguration visible to the user. > > >>>> > > >>>> Signed-off-by: Alexandra Rukomoinikova <[email protected]> > > >>>> --- > > >>>> v1 --> v2: fixed typo in the tests > > >>>> v2 --> v3: fixed hash calculation > > >>>> --- > > >>>> ic/ovn-ic.c | 56 ++++++++++++++-------------- > > >>>> tests/ovn-ic.at | 98 > > >>>> +++++++++++++++++++++++++++++++++++++++++++++++++ > > >>>> 2 files changed, 127 insertions(+), 27 deletions(-) > > >>>> > > >>>> diff --git a/ic/ovn-ic.c b/ic/ovn-ic.c > > >>>> index 95d73cb4b..7d2f9442a 100644 > > >>>> --- a/ic/ovn-ic.c > > >>>> +++ b/ic/ovn-ic.c > > >>>> @@ -1286,6 +1286,7 @@ struct ic_route_info { > > >>>> const char *origin; > > >>>> const char *route_table; > > >>>> const char *route_tag; > > >>>> + struct uuid ic_route_uuid; > > >>>> > > >>>> const struct nbrec_logical_router *nb_lr; > > >>>> > > >>>> @@ -1305,9 +1306,11 @@ struct ic_route_info { > > >>>> static uint32_t > > >>>> ic_route_hash(const struct in6_addr *prefix, unsigned int plen, > > >>>> const struct in6_addr *nexthop, const char *origin, > > >>>> - const char *route_table) > > >>>> + const char *route_table, const struct uuid > > >>>> *ic_route_uuid) > > >>>> { > > >>>> - uint32_t basis = hash_bytes(prefix, sizeof *prefix, > > >>>> (uint32_t)plen); > > >>>> + uint32_t basis = ic_route_uuid ? uuid_hash(ic_route_uuid) : 0; > > >>>> + basis = hash_bytes(prefix, sizeof *prefix, basis); > > >>>> + basis = hash_int((uint32_t) plen, basis); > > >>>> basis = hash_string(origin, basis); > > >>>> basis = hash_string(route_table, basis); > > >>>> return hash_bytes(nexthop, sizeof *nexthop, basis); > > >>>> @@ -1316,18 +1319,22 @@ ic_route_hash(const struct in6_addr *prefix, > > >>>> unsigned int plen, > > >>>> static struct ic_route_info * > > >>>> ic_route_find(struct hmap *routes, const struct in6_addr *prefix, > > >>>> unsigned int plen, const struct in6_addr *nexthop, > > >>>> - const char *origin, const char *route_table, uint32_t > > >>>> hash) > > >>>> + const char *origin, const char *route_table, > > >>>> + const struct uuid *ic_route_uuid, uint32_t hash) > > >>>> { > > >>>> struct ic_route_info *r; > > >>>> if (!hash) { > > >>>> - hash = ic_route_hash(prefix, plen, nexthop, origin, > > >>>> route_table); > > >>>> + hash = ic_route_hash(prefix, plen, nexthop, origin, > > >>>> route_table, > > >>>> + ic_route_uuid); > > >>>> } > > >>>> HMAP_FOR_EACH_WITH_HASH (r, node, hash, routes) { > > >>>> if (ipv6_addr_equals(&r->prefix, prefix) && > > >>>> r->plen == plen && > > >>>> ipv6_addr_equals(&r->nexthop, nexthop) && > > >>>> !strcmp(r->origin, origin) && > > >>>> - !strcmp(r->route_table ? r->route_table : "", > > >>>> route_table)) { > > >>>> + !strcmp(r->route_table ? r->route_table : "", > > >>>> route_table) && > > >>>> + (!ic_route_uuid || uuid_equals(&r->ic_route_uuid, > > >>>> + ic_route_uuid))) { > > >>>> return r; > > >>>> } > > >>>> } > > >>>> @@ -1370,7 +1377,8 @@ parse_route(const char *s_prefix, const char > > >>>> *s_nexthop, > > >>>> static bool > > >>>> add_to_routes_learned(struct hmap *routes_learned, > > >>>> const struct nbrec_logical_router_static_route > > >>>> *nb_route, > > >>>> - const struct nbrec_logical_router *nb_lr) > > >>>> + const struct nbrec_logical_router *nb_lr, > > >>>> + const struct uuid *ic_route_uuid) > > >>>> { > > >>>> struct in6_addr prefix, nexthop; > > >>>> unsigned int plen; > > >>>> @@ -1379,8 +1387,11 @@ add_to_routes_learned(struct hmap > > >>>> *routes_learned, > > >>>> return false; > > >>>> } > > >>>> const char *origin = smap_get_def(&nb_route->options, "origin", > > >>>> ""); > > >>>> + > > >>>> + uint32_t hash = ic_route_hash(&prefix, plen, &nexthop, origin, > > >>>> + nb_route->route_table, > > >>>> ic_route_uuid); > > >>>> if (ic_route_find(routes_learned, &prefix, plen, &nexthop, > > >>>> origin, > > >>>> - nb_route->route_table, 0)) { > > >>>> + nb_route->route_table, ic_route_uuid, hash)) { > > >>>> /* Route was added to learned on previous iteration. */ > > >>>> return true; > > >>>> } > > >>>> @@ -1393,9 +1404,9 @@ add_to_routes_learned(struct hmap > > >>>> *routes_learned, > > >>>> ic_route->origin = origin; > > >>>> ic_route->route_table = nb_route->route_table; > > >>>> ic_route->nb_lr = nb_lr; > > >>>> - hmap_insert(routes_learned, &ic_route->node, > > >>>> - ic_route_hash(&prefix, plen, &nexthop, origin, > > >>>> - nb_route->route_table)); > > >>>> + memcpy(&ic_route->ic_route_uuid, ic_route_uuid, sizeof(struct > > >>>> uuid)); > > >>> There's no need for memcpy here. You can just do a struct assignment: > > >>> > > >>> ic_route->ic_route_uuid = *ic_route_uuid; > > >>> > > >>>> + hmap_insert(routes_learned, &ic_route->node, hash); > > >>>> + > > >>>> return true; > > >>>> } > > >>>> > > >>>> @@ -1562,10 +1573,11 @@ add_to_routes_ad(struct hmap *routes_ad, const > > >>>> struct in6_addr prefix, > > >>>> route_table = ""; > > >>>> } > > >>>> > > >>>> - uint hash = ic_route_hash(&prefix, plen, &nexthop, origin, > > >>>> route_table); > > >>>> + uint hash = ic_route_hash(&prefix, plen, &nexthop, origin, > > >>>> + route_table, NULL); > > >>>> > > >>>> if (!ic_route_find(routes_ad, &prefix, plen, &nexthop, origin, > > >>>> route_table, > > >>>> - hash)) { > > >>>> + NULL, hash)) { > > >>>> struct ic_route_info *ic_route = xzalloc(sizeof *ic_route); > > >>>> ic_route->prefix = prefix; > > >>>> ic_route->plen = plen; > > >>>> @@ -2154,20 +2166,9 @@ sync_learned_routes(struct ic_context *ctx, > > >>>> struct ic_route_info *route_learned > > >>>> = ic_route_find(&ic_lr->routes_learned, &prefix, > > >>>> plen, > > >>>> &nexthop, isb_route->origin, > > >>>> - isb_route->route_table, 0); > > >>>> + isb_route->route_table, > > >>>> + &isb_route->header_.uuid, 0); > > >>>> if (route_learned) { > > >>>> - /* Sync external-ids */ > > >>>> - struct uuid ext_id; > > >>>> - smap_get_uuid(&route_learned->nb_route->external_ids, > > >>>> - "ic-learned-route", &ext_id); > > >>>> - if (!uuid_equals(&ext_id, &isb_route->header_.uuid)) { > > >>>> - char *uuid_s = > > >>>> - xasprintf(UUID_FMT, > > >>>> - > > >>>> UUID_ARGS(&isb_route->header_.uuid)); > > >>>> - > > >>>> nbrec_logical_router_static_route_update_external_ids_setkey( > > >>>> - route_learned->nb_route, "ic-learned-route", > > >>>> uuid_s); > > >>>> - free(uuid_s); > > >>>> - } > > >>>> hmap_remove(&ic_lr->routes_learned, > > >>>> &route_learned->node); > > >>>> free(route_learned); > > >>>> } else { > > >>>> @@ -2275,7 +2276,7 @@ advertise_routes(struct ic_context *ctx, > > >>>> } > > >>>> struct ic_route_info *route_adv = > > >>>> ic_route_find(routes_ad, &prefix, plen, &nexthop, > > >>>> - isb_route->origin, isb_route->route_table, > > >>>> 0); > > >>>> + isb_route->origin, isb_route->route_table, > > >>>> NULL, 0); > > >>>> if (!route_adv) { > > >>>> /* Delete the extra route from IC-SB. */ > > >>>> VLOG_DBG("Delete route %s -> %s from IC-SB, which is not > > >>>> found" > > >>>> @@ -2349,7 +2350,8 @@ build_ts_routes_to_adv(struct ic_context *ctx, > > >>>> if (smap_get_uuid(&nb_route->external_ids, > > >>>> "ic-learned-route", > > >>>> &isb_uuid)) { > > >>>> /* It is a learned route */ > > >>>> - if (!add_to_routes_learned(&ic_lr->routes_learned, > > >>>> nb_route, lr)) { > > >>>> + if (!add_to_routes_learned(&ic_lr->routes_learned, > > >>>> nb_route, lr, > > >>>> + &isb_uuid)) { > > >>>> static struct vlog_rate_limit rl = > > >>>> VLOG_RATE_LIMIT_INIT(5, 1); > > >>>> VLOG_WARN_RL(&rl, "Bad format of learned route in > > >>>> NB: " > > >>>> "%s -> %s. Delete it.", > > >>>> nb_route->ip_prefix, > > >>>> diff --git a/tests/ovn-ic.at b/tests/ovn-ic.at > > >>>> index 1a826aa1c..c633cdeb4 100644 > > >>>> --- a/tests/ovn-ic.at > > >>>> +++ b/tests/ovn-ic.at > > >>>> @@ -4594,3 +4594,101 @@ OVN_CLEANUP_IC([az1], [az2]) > > >>>> > > >>>> AT_CLEANUP > > >>>> ]) > > >>>> + > > >>>> +OVN_FOR_EACH_NORTHD([ > > >>>> +AT_SETUP([ovn-ic -- check loop with annonce duplicated prefixes - > > >>>> multiple ts]) > > >>> s/annonce/announce/ > > >>> > > >>> The same mistake happens a few other times in this test as well. > > >>> > > >>> > > >>> > > >>>> + > > >>>> +ovn_init_ic_db > > >>>> +ovn-ic-nbctl ts-add ts11 > > >>>> +ovn-ic-nbctl ts-add ts12 > > >>>> + > > >>>> +for i in 1 2; do > > >>>> + ovn_start az$i > > >>>> + ovn_as az$i > > >>>> + > > >>>> + # Enable route learning at AZ level > > >>>> + check ovn-nbctl set nb_global . options:ic-route-learn=true > > >>>> + # Enable route advertising at AZ level > > >>>> + check ovn-nbctl set nb_global . options:ic-route-adv=true > > >>>> +done > > >>>> + > > >>>> +for i in 1 2; do > > >>>> + ovn_as az$i > > >>>> + > > >>>> + check ovn-nbctl lr-add lr$i > > >>>> + > > >>>> + check ovn-nbctl lrp-add lr$i lr-lrp-$i aa:aa:aa:aa:a1:0$i > > >>>> 169.254.101.1/24 > > >>>> + check ovn-nbctl lsp-add-router-port ts11 lsp-az$i lr-lrp-$i > > >>>> + > > >>>> + # Create subnet for annonce. > > >>>> + check ovn-nbctl lrp-add lr$i lr-lrp-subnet-$i aa:aa:aa:aa:a2:0$i > > >>>> 192.168.0.$i/24 > > >>>> + > > >>>> + # Create one more lrp-ts port through another transit switch. > > >>>> + check ovn-nbctl lrp-add lr$i lr-lrp-dup$i aa:aa:aa:aa:a3:01 > > >>>> 169.254.101.1/24 > > >>>> + check ovn-nbctl lsp-add-router-port ts12 lsp-dup-az$i lr-lrp-dup$i > > >>>> +done > > >>>> + > > >>>> +OVS_WAIT_FOR_OUTPUT([ovn_as az1 ovn-nbctl lr-route-list lr1 | grep > > >>>> 192.168 | > > >>>> + grep learned | awk '{print $1, $2}' | sort ], > > >>>> [0], [dnl > > >>>> +192.168.0.0/24 169.254.101.1 > > >>>> +192.168.0.0/24 169.254.101.1 > > >>>> +]) > > >>>> + > > >>>> +OVN_CLEANUP_IC([az1], [az2]) > > >>>> +AT_CLEANUP > > >>>> +]) > > >>>> + > > >>>> +OVN_FOR_EACH_NORTHD([ > > >>>> +AT_SETUP([ovn-ic -- check loop with annonce duplicated prefixes - > > >>>> single ts]) > > >>>> + > > >>>> +ovn_init_ic_db > > >>>> + > > >>>> +for i in 1 2 3; do > > >>>> + ovn_start az$i > > >>>> + ovn_as az$i > > >>>> + > > >>>> + # Enable route learning at AZ level > > >>>> + check ovn-nbctl set nb_global . options:ic-route-learn=true > > >>>> + # Enable route advertising at AZ level > > >>>> + check ovn-nbctl set nb_global . options:ic-route-adv=true > > >>>> +done > > >>>> + > > >>>> +# Create new transit switches and LRs. Test topology is next: > > >>>> +# logical router (lr12) > > >>>> +# | > > >>>> +# logical router (lr11) - / transit switch (ts11) \ - logical router > > >>>> (lr13) > > >>>> +# > > >>>> + > > >>>> +# Create lr11, lr13, ts11 and connect them > > >>>> +for i in 1 3; do > > >>>> + ovn_as az$i > > >>>> + > > >>>> + check ovn-nbctl lr-add lr1$i > > >>>> + check ovn-ic-nbctl --wait=sb --may-exist ts-add ts11 > > >>>> + > > >>>> + # Create LRP and connect to TS > > >>>> + check ovn-nbctl lrp-add lr1$i lrp-lr1$i-ts11 aa:aa:aa:aa:a1:0$i > > >>>> 169.254.101.1/24 > > >>>> + check ovn-nbctl lsp-add-router-port ts11 lsp-ts11-lr1$i > > >>>> lrp-lr1$i-ts11 > > >>>> +done > > >>>> + > > >>>> +# Create lr12 and connect it to ts11 > > >>>> +ovn_as az2 > > >>>> +check ovn-nbctl lr-add lr12 > > >>>> + > > >>>> +# Create LRP and connect to TS > > >>>> +check ovn-nbctl lrp-add lr12 lrp-lr12-ts11 aa:aa:aa:aa:a1:03 > > >>>> 169.254.101.2/24 > > >>>> +check ovn-nbctl lsp-add-router-port ts11 lsp-lr12-ts11 lrp-lr12-ts11 > > >>>> + > > >>>> +# Create directly-connected route in lr11 > > >>>> +check ovn_as az1 ovn-nbctl lrp-add lr11 lrp-lr11 aa:aa:aa:aa:bb:01 > > >>>> "192.168.0.1/24" > > >>>> +check ovn_as az3 ovn-nbctl lrp-add lr13 lrp-lr13 aa:aa:aa:aa:bb:03 > > >>>> "192.168.0.1/24" > > >>>> + > > >>>> +OVS_WAIT_FOR_OUTPUT([ovn_as az2 ovn-nbctl lr-route-list lr12 | grep > > >>>> 192.168 | > > >>>> + grep learned | awk '{print $1, $2}' | sort ], > > >>>> [0], [dnl > > >>>> +192.168.0.0/24 169.254.101.1 > > >>>> +192.168.0.0/24 169.254.101.1 > > >>>> +]) > > >>>> + > > >>>> +OVN_CLEANUP_IC([az1], [az2], [az3]) > > >>>> +AT_CLEANUP > > >>>> +]) > > >>>> -- > > >>>> 2.48.1 > > >>>> > > >>>> _______________________________________________ > > >>>> dev mailing list > > >>>> [email protected] > > >>>> https://mail.openvswitch.org/mailman/listinfo/ovs-dev > > >>>> > > >>> _______________________________________________ > > >>> dev mailing list > > >>> [email protected] > > >>> https://mail.openvswitch.org/mailman/listinfo/ovs-dev > > >> > > >> Thank you Alexandra and Mark, > > >> > > >> I'm slightly confused; the commit message says it's a fix, but there > > >> isn't a Fixes tag. Also based on the commit message about invalid > > >> configuration I don't think this needs a backport, please let me know if > > >> that's not the case. I've fixed the nits and applied to main. > > >> > > >> Regards, > > >> Ales > > > Hi Ales, > > > > > > A specific invalid configuration can cause `ovn-nbctl lr-route-list` > > > to loop infinitely, listing the same routes forever. If you try to run > > > the first new test added in this patch on an unpatched OVN main, then > > > the test fails because it continuously lists "192.168.0.0/24 > > > 169.254.101.1" in its output. This patch is ensuring that this invalid > > > configuration allows `ovn-nbctl lr-route-list` to work as expected. > > > > > > I tried to find what an appropriate "Fixes" tag would be, but I had > > > trouble pinpointing it. The issue of hash collisions for identical > > > routes appears to have existed since route advertising was added to > > > ovn-ic (57b347c55 ("ovn-ic: Route advertisement.")). I believe this > > > patch needs to be backported all the way down to branch-24.03. I > > > confirmed that if I apply the first test from this patch to > > > branch-24.03 and running it there, I see the same infinite loop > > > behavior as I see in unpatched main. > > > > > Sorry for the noise, I don't think I can read. I thought my patch wasn't > > working on 24.03, and after checking that it was working, I realized I > > must have misread your email =) > > > > -- > > regards, > > Alexandra. > > Yes, sorry for the confusion. I was trying to instruct Ales that the > patch needs to be backported all the way back to branch-24.03. I was > showing that your test reveals that the bug exists in 24.03.
I realize that the word "instruct" here makes it sound like I'm ordering Ales to do the backport. But I'll take care of it instead. I'll reply when I'm done. > > _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
