Activity

1. jk-ozlabs

   self-assigned this

   on Mar 30, 2026
2. faizana-nvidia commented on Jul 27, 2026

   

   faizana-nvidia

   on Jul 27, 2026

   Contributor

   More actions

   Hello @jk-ozlabs

   I too was looking for this, if you still haven't picked it up as your current working item, I'll be happy to push a change.
3. jk-ozlabs commented on Jul 28, 2026

   

   jk-ozlabs

   on Jul 28, 2026

   MemberAuthor

   More actions

   @faizana-nvidia sure, if you want to look at this!

   I'd suggest working out a plan here before writing the implementation though, there are some design points for the recovery flow that we would need to sort out too. Mainly:

   • we'll probably want to check connectivity to the bridge too
   • we'll need to handle cases where the EID has been reassigned by the downstream bus owner (ie, has a new UUID), by generating a remove & re-add.
4. faizana-nvidia commented on Jul 28, 2026

   

   faizana-nvidia

   on Jul 28, 2026

   Contributor

   More actions

   great! let me update here with the flow
5. faizana-nvidia commented on Aug 13, 2026

   

   faizana-nvidia

   on Aug 13, 2026

   Last edited by faizana-nvidia

   Contributor

   More actions

   Downstream Endpoint Recovery Flow

   method_endpoint_recover (D-Bus entry point) — unchanged for both peer types

   flowchart TD
       A([method_endpoint_recover called]) --> B{peer->degraded?}
       B -- yes --> Z([no-op, return OK])
       B -- no --> C["set recovery.npolls, recovery.delay\nschedule peer_endpoint_recover timer\npeer->degraded = true\nemit Connectivity changed"]
       C --> D([return — common for direct and downstream peers])
   

   Loading

   ---

   peer_endpoint_recover (timer callback) — downstream branch inserted after physical probe

   flowchart TD
       TIMER([timer fires: peer_endpoint_recover]) --> DEC[Decrement recovery.npolls]
   
       DEC --> PHYS["[EXISTING — unchanged]\nPhysical probe\nquery_get_endpoint_id\n  dest=peer->phys, peer=NULL\n  → for direct: tests the device\n  → for downstream: tests the bridge\nstores result in recovery.eid"]
   
       PHYS --> PHYSOK{responded?}
       PHYSOK -- no --> RESCHED
   
       PHYSOK -- yes --> BRIDGE["[NEW]\nfind_bridge_for_peer:\nscan peers for p where\n  p.pool_size > 0\n  && match_phys(p.phys, peer.phys)\n  && p.pool_start <= peer.eid\n       < p.pool_start + p.pool_size"]
   
       BRIDGE --> ISBRIDGE{downstream\npeer?}
   
       %% ── DOWNSTREAM BRANCH (new) ──────────────────────────────
       ISBRIDGE -- "yes\n(bridge found)" --> EIDRP["[NEW — downstream only]\nEID-routed probe\nquery_get_endpoint_id\n  dest=peer->phys, peer=peer\n  → routed through bridge to device\noverwrites recovery.eid with\ndownstream device's EID"]
   
       EIDRP --> EIDOK{responded?}
       EIDOK -- no --> RESCHED
   
       EIDOK -- yes --> UUIDQ["[NEW — downstream only]\nUUID via EID routing\nquery_get_peer_uuid_by_eid\n  → gets downstream device UUID\n  not the bridge UUID"]
   
       UUIDQ --> UUIDOK{UUID query\nsucceeded?}
       UUIDOK -- no --> RECLAIM
   
       UUIDOK -- yes --> UUIDMATCH{UUID matches\npeer->uuid?}
   
       UUIDMATCH -- "yes — same device" --> EIDMATCH{recovery.eid\n== peer->eid?}
       EIDMATCH -- yes --> SUCCESS
       EIDMATCH -- "no — EID drifted\nbridge is bus owner,\ncannot send Set Endpoint ID" --> RECLAIM
   
       UUIDMATCH -- "no or nil UUID\nnew device at this EID" --> READD["[NEW — downstream only]\nBridge re-assigned EID to new device\n\nsave phys / eid / net\nremove_peer old  → emits EndpointRemoved\nadd_peer eid, net, allow_bridged=true\nsetup_added_peer new  → emits EndpointAdded"]
       READD --> DONE([return])
   
       %% ── DIRECT ENDPOINT BRANCH (existing, unchanged) ─────────
       ISBRIDGE -- "no\n(direct endpoint)" --> DIRECT["[EXISTING — unchanged]\nif recovery.eid != peer->eid:\n  query_get_peer_uuid_by_phys\n  UUID mismatch → remove_peer\n                  + endpoint_assign_eid\n  UUID match    → endpoint_send_set_endpoint_id\n                  + change_peer_eid"]
       DIRECT --> SUCCESS
   
       %% ── SHARED SUCCESS PATH (existing, unchanged) ────────────
       SUCCESS(["[EXISTING — unchanged]\npeer->degraded = false\nemit Connectivity changed\nunref recovery.source\nzero recovery.delay / npolls"])
   
       %% ── SHARED RESCHEDULE / RECLAIM (existing, unchanged) ────
       RESCHED{recovery.npolls > 0?}
       RESCHED -- yes --> RETRY[reschedule timer\nat recovery.delay]
       RESCHED -- no --> RECLAIM
       RECLAIM([reclaim: remove_peer])
   

   Loading

   ---
6. faizana-nvidia commented on Aug 13, 2026

   

   faizana-nvidia

   on Aug 13, 2026

   Contributor

   More actions

   Updating the flow here, will create PR for the same if this flow looks okay.
7. amboar commented on Oct 1, 2026

   

   amboar

   on Oct 1, 2026

   Contributor

   More actions

   I find that mermaid diagram tricky to comprehend. A text description may help.
8. faizana-nvidia commented on Oct 1, 2026

   

   faizana-nvidia

   on Oct 1, 2026

   Contributor

   More actions

   I find that mermaid diagram tricky to comprehend. A text description may help.

   yeah its outdated now, flow has changed a bit based on review discussion on #175

   👍React with 👍1Reacted by Andrew Jeffery