[the-gigi-pplx]

Summary

Lets a Kubernetes sandbox's runtime upgrade boot where its microVM actually launches: in the pod's containerd shim at container create. A restore pod with the new space.pplx.net/checkpoint: runtime-upgrade makes the shim call sandbox-manager's UpgradeRuntime with the pod's network namespace, instead of the ordinary Start that boots the old environment. This is the node half only. Nothing renders the new pod yet, so merging it changes no running sandbox, except that sandbox-manager now refuses a Wake carrying runtime_upgrade for a Kubernetes route identity.

Terms

• Runtime upgrade: sandbox-manager's UpgradeRuntime, added in PR [sbx-mgr] upgrade a stopped or suspended sandbox runtime by fenced cold boot and retire its checkpoint #986. It fences a stopped or suspended sandbox (a sandbox_runtime_upgrades row), preserves its disk, saves the target execution environment as the consumer, cold-boots it, and retires the old checkpoint or rolls back.
• Route identity: the SpaceApiRouteIdentity an activation carries. On Kubernetes it names the pod (pod_uid, execution_generation, substrate_kind: KUBERNETES); Direct activations name no pod.
• Placeholder task: the shim task a pod runs when its sandbox stays stopped with no microVM, introduced for stopped materialization in PR [cluster-controller] re-place an evacuated stopped sandbox as stopped on another node, materialized by the shim without a VM #826 (markMaterializedStopped). It's detached, so Kill and Delete never reach sandbox-manager, and it refuses exec, pause, resume and checkpoint.
• Activate in place: for a started target, UpgradeRuntime itself starts or restores a sandbox that's already on the target, so the pod gets its execution from one RPC.

The problem

On Kubernetes, a sandbox's VM launches in its pod's shim when containerd creates the container, never from the control plane's Wake. The upgrade paths built so far send the upgrade on the Wake instead:

1. A stopped upgrade boots the old environment. The restore pod's checkpoint is stopped. For a sandbox stopped on the node, stoppedRestartCheckpoint (shim/space.go) clears it and the shim sends a plain Start, which carries no upgrade, so the sandbox boots under the environment it's moving off. The Wake that carries the upgrade has no network namespace (netns_path: None with a Kubernetes identity), so sandbox-manager refuses its launch with MISSING_RUNTIME_CONTEXT before the upgrade runs.
2. Resume- and start-time upgrades from PR [api] decide the runtime upgrade at resume and start, and stage pod-less sandboxes on the node #1015 have the same flaw. Their Kubernetes Wakes also carry no namespace. Once the shim's Start has booted the sandbox, the Wake's Started arm never reads runtime_upgrade, so with SPACE_RUNTIME_UPGRADE_AT_ACTIVATION_ENABLED on, a decided upgrade boots the old environment and reports success. The flag is off by default, so this is dormant.

Nothing in the node gives the pod a way to ask for the upgrade itself, or gives the control plane a way to learn the outcome of an upgrade it didn't call.

How this fixes it

• Pod contract. SandboxPodRequest::Restore gains runtime_upgrade: Option<Box<PodRuntimeUpgrade>> (crates/libs/common/core/src/k8s/runtime_upgrade.rs). It renders checkpoint: runtime-upgrade and space.pplx.net/runtime-upgrade-* annotations: operation id, target environment, authorization id and reason, memory-loss consent, target state (started or stopped), and for a suspended source the checkpoint's local artifact id. Golden snapshots pin the stopped, started and suspended shapes.
• Shim mode. On runtime-upgrade the shim parses the annotations strictly (shim/runtime_upgrade.go). It turns the Start it would send, with the pod's namespace and route identity, into the plain blocking cold start the upgrade boots, and calls UpgradeRuntime. A suspended source's storage URI and source node become stage_from. Any error, an unspecified outcome, or a started target with no running execution fails the create; nothing falls back to Start. A started target attaches the returned pid. A stopped target runs the PR [cluster-controller] re-place an evacuated stopped sandbox as stopped on another node, materialized by the shim without a VM #826 placeholder task. Upgrade annotations on any other pod are refused, and so is an upgrade pod that also names a stopped materialization or a fork-disk restore.
• UpgradeRuntime for a pod (crates/l40_api/sbx/mgr/server/src/service/runtime_upgrade/rpc.rs). Under the sandbox's upgrade lock, the RPC now:
  • stages a suspended sandbox absent from the node from stage_from, which takes the authority a Start with a namespace takes (Root, Admin or node-api, not a local operator), leaving it suspended and never launched, and only for a request that names the checkpoint (checkpoint_local_artifact_id). Staging runs before the upgrade's own checks, so an upgrade refused afterwards leaves the staged sandbox suspended on the node, and resumes a stage that was interrupted after it adopted the row (stage_missing_checkpoint, shared with the Wake's upgrade);
  • for a suspended sandbox, upgrades only from the checkpoint checkpoint_local_artifact_id names. The upgrader itself now checks this under its disk-mutation exclusion, for the Wake and the RPC alike, and a Wake checks it again after a replay, before it restores anything;
  • refuses, before staging anything, a request whose operation id the node recorded for another sandbox, target or authorization. An operation id names one upgrade of one sandbox across both tables, checked inside the fence's transaction and the outcome's write, so two requests reusing one id can't both succeed; the loser is refused with InvalidArgument, as an early check would refuse it. An operation that found its sandbox on the target never boots it on a replay;
  • answers from the sandbox as it is when the call ends, never from the boot alone, since retirement runs after the boot and the sandbox may have moved meanwhile. A stopped target is answered only for a sandbox that's stopped or suspended; one another activation or stop is still moving, or whose pending cleanup recovery is still driving, is refused with Unavailable, so a retry finds where it lands. A started target always returns the running execution, and to a pod only the execution that pod runs; a caller that names no pod, such as an operator upgrading a Direct sandbox, gets whatever execution runs. A stopped sandbox already on the target cold-starts with the pod's start, and a suspended one restores its checkpoint; the pod's answer is then read from the sandbox, not taken from the start's response, so a stop or suspend that finished in between, which keeps the pod's identity on the row, is refused rather than answered with a stale pid. An operation starts the sandbox at most once: the start of a stopped or suspended sandbox is claimed durably before it runs, with the node execution the sandbox has then. A retry may start it again only while it's still at rest on that execution, so a start refused before its activation claimed the sandbox (staging busy, admission) is retried, and once any activation has claimed it the retry is answered by the replay rule below. The activation's own claim, in its transaction, checks the sandbox is still on that execution, so an ordinary start and stop that ran while the upgrade's start waited is never undone. An operation answered with the execution already running records that answer as its activation too, so a retry after a later stop never starts the sandbox. GetRuntimeUpgrade reports either as activation_claimed; a claimed start is written before it runs and may still have failed, so the flag alone doesn't say the sandbox runs;
  • for a sandbox already started, or a replay of an upgrade that already retired, returns the live execution only when its route identity names the same pod (pod UID and execution generation), and refuses with FailedPrecondition otherwise. A replay never moves the sandbox.
• GetRuntimeUpgrade. A new read-only RPC (restart admission ReadOnly) reports an operation as absent, in progress (with its phase), upgraded, rolled back (with its failure) or already on target. A rolled-back upgrade deletes its row and an already-on-target one never wrote one, so both outcomes now go to a new sandbox_runtime_upgrade_outcomes table. A live row for the same operation wins over a recorded outcome. The report is the upgrade's outcome, not the pod's: an upgrade can be recorded while the pod's create was refused, so the control plane reads it with the pod's status. A recorded outcome keeps what its operation asked for, so a retry under the same operation id that names another sandbox, target state, environment or authorization is refused, as for a live row. Node-api forwards the RPC on WorkerApiInternal only for a caller with the control-plane authority a policy write needs, the authority its Wake requires for runtime_upgrade.
• Wake restore stack. A Direct Wake that restores a suspended sandbox, including one that first replays a retired upgrade, has to fit the 2 MiB test stack of an unoptimized build, the profile CI tests sbx-mgr with. main boxes the start inside start_sandbox_with_authority, which keeps it within that stack; this PR adds the test that drives the replay-then-restore path there.
• Restore's local snapshot check reads the service's cache root. start.rs decided whether a restore stages its snapshot remotely by looking under the fixed cache directory, while the checkpoint launch that follows reads the service's cache root. In production the two are the same directory; in a test the check now looks where the test wrote the snapshot, so the restore tests here reach the checkpoint launch in milliseconds instead of waiting out a remote stage-in's cleanup.
• Wake refusal. A Wake carrying runtime_upgrade is refused with FailedPrecondition, before anything is staged, fenced or booted, when its route identity or the sandbox's local row names a Kubernetes pod. Direct keeps its Wake path, since Direct launches from the Wake.

Unchanged: the upgrade's fence, preserve, boot, settle and recovery phases, and the Direct Wake upgrade. The api half, which renders the pod for stopped upgrades, moves PR #1015's start and resume onto it, and waits on GetRuntimeUpgrade instead of the Wake, is PR #1322's job.

Trust boundary. The upgrade's authorization, including consent to discard a suspended sandbox's memory, arrives as pod annotations that only the api writes. Any principal that can create sandbox pods can request an upgrade. The node still refuses any move that isn't a certified upgrade edge from the environment the sandbox ran under. The shim runs under containerd as root, which uds-peer-auth classifies as Root, a member of ALLOW_SANDBOX_RUNTIME_UPGRADE. The shim already passes a network namespace, which takes ALLOW_SANDBOX_START_CONTEXT, and the existing every_caller_allowed_a_wake_start_context_may_also_upgrade pins that list as a subset of the upgrade's.

Validation

All tests below use Kubernetes route identities, never Direct.

• service::runtime_upgrade::rpc::tests (sbx-mgr, 28 tests) against a test-served node-manager:
  • a_pods_upgrade_boots_in_the_pods_namespace_under_the_target: with the pod's namespace, the upgrade reaches its cold boot (the rollback restores the preserved disk, which only a boot-phase rollback does), never fails on the missing runtime context, and reports ROLLED_BACK with the failure.
  • a_replay_of_a_finished_upgrade_answers_only_the_pod_that_runs_it: a retired replay returns the live pid only to the running pod. Another pod, an earlier generation, a stopped sandbox, and an identity with no pod are refused, and nothing moves.
  • an_upgrade_already_on_its_target_is_recorded_and_replays_the_same, a_started_target_already_reached_is_activated_in_place, a_started_sandbox_already_on_its_target_answers_only_its_own_pod, a_suspended_sandbox_already_on_its_target_is_restored_in_place.
  • a_pods_upgrade_of_a_suspended_sandbox_needs_the_decided_checkpoint, an_absent_suspended_sandbox_is_staged_before_the_upgrade, an_interrupted_stage_is_resumed_before_the_upgrade, staging_leaves_a_present_sandbox_to_the_upgrade, an_activated_upgrade_never_starts_its_sandbox_again.
  • a_kubernetes_wake_refuses_a_runtime_upgrade, with and without a namespace, and a_wake_for_a_kubernetes_row_refuses_a_runtime_upgrade_whatever_it_claims.
  • a_wake_replay_of_a_retired_upgrade_never_restores_a_newer_checkpoint: with the checkpoint check now in the upgrader, a Direct Wake replaying a retired upgrade is still refused when the node pins a newer checkpoint than the one it names. a_stopped_target_replay_ignores_a_newer_checkpoint: a replay that restores nothing still answers upgraded.
  • a_wake_replay_of_a_retired_upgrade_goes_on_to_restore: a Direct Wake replays a retired upgrade and reaches the checkpoint launch at opt-level 0. With the start unboxed it aborts with a stack overflow.
  • a_stopped_target_never_answers_for_a_running_sandbox: a stopped-target upgrade that finds the sandbox running on its target is refused, not reported as stopped, and a_stopped_target_replay_never_answers_for_a_running_sandbox does the same for a replay. a_reused_operation_id_stages_nothing: an operation id recorded for another sandbox stages nothing for the one a request names.
  • staging_takes_a_starts_authority: a local operator may not stage. staging_leaves_a_present_sandbox_to_the_upgrade also refuses stage_from without a checkpoint id. an_operation_that_found_its_target_never_boots_on_a_replay and an_activation_meeting_a_moving_sandbox_is_retryable.
  • a_recorded_operation_cant_be_retried_as_another: an operation that found its sandbox on the target for a stopped lifecycle can't be retried as a start.
  • an_old_shims_runtime_upgrade_start_is_refused_on_a_stopped_suspended_or_absent_sandbox: what a shim that predates the checkpoint sends fails closed on a stopped row and on a suspended row, with nothing launched or staged, and an absent sandbox is reported not found rather than materialized.
  • a_stopped_target_meeting_a_moving_sandbox_is_retryable: a stopped target that finds the sandbox stopping or with a cleanup pending is refused with Unavailable, as a started target is.
  • the_runtime_upgrade_report_is_read_only_by_the_upgrades_principals: an operator reads a report, and a peer the node doesn't know is refused.
  • an_activation_in_place_answers_only_a_sandbox_still_running_the_pods_execution: after the start returns, a sandbox running the pod's execution answers with its live pid; one stopped or suspended in between with the pod's identity still on the row, or started with its runtime gone, is refused.
  • an_operation_answered_with_a_running_execution_never_starts_it_after_a_stop: an operation answered with the running execution, retried after a later stop by a caller that names no pod, is refused and starts nothing.
• Store tests in db::runtime_upgrades::tests: the report through every phase, a rollback's failure kept after its row goes and superseded by a retry, an already-on-target outcome that another sandbox, or the same operation asking for another lifecycle, can't rewrite, an operation id kept to one sandbox across both tables, an activation claimed once, with the execution it was claimed from, and kept across replays, an answer with a running execution recorded as the operation's activation, an_activation_decided_on_an_execution_refuses_a_sandbox_moved_off_it (the activation's claim refuses a sandbox another activation moved off the execution it was decided on), the request each recorded outcome keeps, and outcomes deleted with the sandbox.
• worker::tests::the_internal_runtime_upgrade_report_is_forwarded_only_for_the_control_plane (node-api).
• sandbox_pod_shapes_render_expected_yaml with three new shapes: sandbox_pod_restore_runtime_upgrade_{stopped,started,suspended}.
• Shim (go test ./...): TestARuntimeUpgradePodNeverFallsBackToStart drives Create with every failing answer and asserts no Start or State call. Other tests cover the started pid, the stopped placeholder, staging for a suspended source, strict annotation parsing (including an upgrade pod that names another restore intent), and TestTheShimParsesEveryRenderedRuntimeUpgradePod, which parses the Rust renderer's golden snapshots.
• Each guard was mutated and the suite re-run, and every shim and Rust mutant failed a test, with two exceptions. Removing the outcome table's explicit delete in delete_sandbox_child_rows survives, because the table's ON DELETE CASCADE still deletes the rows. Mapping the fence's cross-table refusal to another status survives, because only two concurrent requests reach it past the early check; the store test covers the refusal itself.
• The full workspace at this head with CI's own entry points on a Linux build box: run-rust-checks.sh tests-unprivileged passed all 12,345 tests, within the test-duration budget, plus doctests, feature isolation and the SDK dependency checks. The privileged lane passed 70 of 76. Its six failures come from the box, not this change, and fail the same way on main on the same box: the three fs-verity tests (the box kernel exposes no verity ioctls), two contained_launcher tests that reject the box's non-root-owned path ancestors, and spaced-guest-worker::embedding, which needs the private cgroup namespace CI sets. CI's privileged lane covers them.
• cargo clippy --workspace --all-targets --all-features -- -D warnings, cargo arch with the base baseline (advisory findings only), gofmt, go vet. The Go protos were regenerated with the pinned protoc 35.0 and protoc-gen-go v1.36.11.

Not validated: a Kind or deployed run. Nothing renders the new pod until the api half lands, so there's no end-to-end path to drive yet. This unit harness can't launch, so two things are proven only below the RPC: the activation claim's execution check is tested in the store, not through a Start that reaches it, and no test drives a successful activation in place end to end. The answer that follows it is tested on its own (an_activation_in_place_answers_only_a_sandbox_still_running_the_pods_execution).

Dependencies

None. This merges on its own. It builds on PR #826's placeholder task, which is on main. PR #1322 depends on this PR.

Rollout

Ship the shim and sandbox-manager before the api renders runtime-upgrade pods, and only once every node's sandbox-manager is from this release: an older one ignores stage_from and checkpoint_local_artifact_id, so it would upgrade whatever copy of a suspended sandbox the node holds. A shim that predates the checkpoint passes it through as a Start checkpoint, which sandbox-manager refuses for a local row in any state and for a sandbox absent from the node, so the pod fails without booting. A sandbox-manager that predates activation answers ALREADY_ON_TARGET with no execution, and this shim fails the create. The new SQLite table is an additive migration, and a rollback build keeps it (see Severity and risk).

Leave SPACE_RUNTIME_UPGRADE_AT_ACTIVATION_ENABLED off on Kubernetes: with it on, sandbox-manager now refuses the upgrade Wake, so every activation that decides an upgrade fails until the api half lands. docs/configuration.md says so.

Not covered

Two items for the api's enablement of these pods, which the api half (#1322) takes on before it renders them:

• Capability negotiation, so a newer shim doesn't rely on stage_from and checkpoint_local_artifact_id against an older sandbox-manager during a partial rollout or rollback.
• Recording memory-loss consent as part of an operation's identity.

Severity and risk

Severity: medium. Without this, a runtime upgrade of a Kubernetes sandbox can't take effect once the api starts requesting one. Nothing requests one today.

Risk: low. The new pod mode and GetRuntimeUpgrade have no caller until the api half lands. The behavior change on main is the Kubernetes Wake refusal, which only a cluster with the flag on reaches, where it fails instead of silently booting the old environment. UpgradeRuntime has no other production caller. Roll back by reverting the code but keeping the sandbox_runtime_upgrade_outcomes migration (its files under db/sandbox-manager/ and its entry in the store's migration list): a node that ran this release has applied it, and an older sandbox-manager refuses a database whose history holds a migration it doesn't bundle. The table stays behind, unread.

Docs

docs/execution-environments.md adds "Booting an upgrade in its pod", notes that a rolled-back or already-on-target upgrade keeps its outcome, and notes in "Upgrading at resume and start" that the Wake now refuses a Kubernetes upgrade. docs/configuration.md says to leave SPACE_RUNTIME_UPGRADE_AT_ACTIVATION_ENABLED off on Kubernetes until then.

AI assistance: Claude Code drafted the code, tests, docs and this description, under the author's direction and review.

[mabdelraouf-pplx]

Two blocking issues:

1. In activate_once, after activate_on_target succeeds, the final check only calls runs_for_caller and then returns the original response. Stop/Suspend clears the live runtime but retains the pod UID and execution generation, so a concurrent teardown can complete before this check and the shim will accept a stale nonzero PID for a sandbox that is no longer running. Please revalidate with running_execution_for and return its fresh response, with a regression covering teardown before the RPC answer.

2. The rollout says rollback is a commit revert, but the new SQLite migration is applied at startup and SQLite history validation rejects applied versions missing from the binary's bundled catalog. Reverting this commit removes that migration from the catalog, so sandbox-manager cannot restart on nodes that applied it. The rollback artifact must retain the migration and schema metadata, or the rollout needs a tested service-stopped down-migration/state-preservation procedure.

[coderabbitai]

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Walkthrough

The changes add Kubernetes runtime-upgrade pod metadata and RPCs, persist upgrade outcomes and activation claims, and update sandbox-manager start and replay handling. The shim parses upgrade annotations and calls UpgradeRuntime for upgrade pods without falling back to Start. The outcome-report RPC returns operation status, phase, failure details, and activation-claim state. Tests cover validation, staging, retries, activation, authorization, and reporting.

Merge Risk: Moderate · up to e498a

This adds a Kubernetes pod-based runtime-upgrade path, durable upgrade outcomes in a new SQLite table, and one-time activation claims. Nothing renders the upgrade pods yet, which limits exposure. The new migration means a rollback must keep the migration files, otherwise sandbox-manager will not start, and the documented rollout order must be followed. In-place activation has not been exercised end to end, so it should be validated on a deployed environment before the API starts rendering these pods.

Security architecture risk: Moderate · up to e498a

The upgrade path gains meaningful execution-identity and retry protections. No introduced security defect was established, but the change crosses privileged boundaries and depends on correct deployment ordering and recovery behavior.

Retained concerns
No architecture-level concerns identified.

Security review details

Security Blast Radius

• inferred — The independently privileged scope is not inherently one tenant: authorized local lifecycle principals can address sandbox IDs served by the manager, and sandbox-pod writers can submit upgrade intent through the shim. Tenant containment therefore depends on upstream pod-write and control-plane authority boundaries, whose deployed configuration was not inspected.

Trust Boundaries and Controls

• observed — The existing peer authorizer derives local identity from Unix-socket credentials and denies unauthorized principals. UpgradeRuntime and GetRuntimeUpgrade use the runtime-upgrade permission; staging additionally requires Start-context permission. Report lookup rejects operation records belonging to another sandbox. The supplied report test covers an allowed operator and denial of an unknown UID.

Resilience and Maintainability Implications

• observed — A pre-start failure can leave activation claimed without reporting RPC success. Retry is allowed only while the sandbox remains at rest on the claimed prior execution; activation admission rechecks that execution transactionally. Moving or cleanup states are refused, and subsequent success requires a live matching execution rather than the durable flag alone.

Hardening Proposals

• proposed — Before enabling upgrade-pod production, enforce the documented minimum manager capability across eligible nodes and verify that sandbox-pod creation remains restricted to intended control-plane principals. This is a rollout safeguard, not an observed bypass.

Pre-merge checks: 5

Check name	Status	Explanation
Title check		The title uses the valid [sbx-mgr] area format, starts its summary with the lowercase word "boot," accurately describes the Kubernetes runtime-upgrade pod and shim changes, and has no trailing period,…
Description Follows The Pr Template		The description contains all required PR template sections and content: ## Summary explains the merge effect; ## Validation names tests and reports results; ## Severity and risk gives severity a…
Bug Fixes Name A Regression Test		The pull request fixes application behavior under crates/ and shim/. Its Validation section names regression tests, including `an_activation_in_place_answers_only_a_sandbox_still_running_the_pods_exec…
Weakened Safeguards Are Justified		No weakened test, lint, CI, or repository guard is introduced. The only removed test assertions are in runtime_upgrade/tests.rs; they follow the intentional removal of start from `RuntimeUpgradeOu…
Public-Safe Content		PASS. The reviewed diff contains no credentials, tokens, private keys, internal hostnames or private links, cloud ARNs, workstation paths, production logs, or incident details. The absolute paths and …

Full details: Title check

Explanation

The title uses the valid [sbx-mgr] area format, starts its summary with the lowercase word "boot," accurately describes the Kubernetes runtime-upgrade pod and shim changes, and has no trailing period, ticket ID, or internal link.

Full details: Description Follows The Pr Template

Explanation

The description contains all required PR template sections and content: ## Summary explains the merge effect; ## Validation names tests and reports results; ## Severity and risk gives severity and risk; and AI assistance: identifies Claude Code and the drafted or changed parts.

Full details: Bug Fixes Name A Regression Test

Explanation

The pull request fixes application behavior under crates/ and shim/. Its Validation section names regression tests, including an_activation_in_place_answers_only_a_sandbox_still_running_the_pods_execution, and states that mutated guards failed tests. The changed RPC code now re-reads the sandbox after activation, and the test covers stop, suspend, and missing-runtime cases before returning a PID.

Full details: Weakened Safeguards Are Justified

Explanation

No weakened test, lint, CI, or repository guard is introduced. The only removed test assertions are in runtime_upgrade/tests.rs; they follow the intentional removal of start from RuntimeUpgradeOutcome. The new RPC tests assert returned PIDs and replay behavior, while the other assertions are updated to the new Replayed variant. No CI, allowlist, lint, or test-configuration file changes are present.

Full details: Public-Safe Content

Explanation

PASS. The reviewed diff contains no credentials, tokens, private keys, internal hostnames or private links, cloud ARNs, workstation paths, production logs, or incident details. The absolute paths and UUIDs are test/runtime fixtures, and the S3 test URI and Kubernetes registry reference are established test values. The description contains only a public GitHub repository link.

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Commits

Reviewing files that changed from the base of the PR and between d1a1b41 and e498a04.

Files ignored due to path filters: 5

• crates/libs/common/core/src/fixtures/sandbox_pod_restore_runtime_upgrade_started.snap is excluded by !**/*.snap
• crates/libs/common/core/src/fixtures/sandbox_pod_restore_runtime_upgrade_stopped.snap is excluded by !**/*.snap
• crates/libs/common/core/src/fixtures/sandbox_pod_restore_runtime_upgrade_suspended.snap is excluded by !**/*.snap
• shim/proto/sandbox/manager/v1/manager.pb.go is excluded by !**/*.pb.go, !**/*.pb.go
• shim/proto/sandbox/manager/v1/manager_grpc.pb.go is excluded by !**/*.pb.go, !**/*.pb.go

Files selected for processing: 4

• crates/l30_storage/sbx/mgr/store/src/db/runtime_upgrades.rs
• crates/l40_api/sbx/mgr/server/src/service/runtime_upgrade/rpc.rs
• db/sandbox-manager/20261102233341_sandbox_runtime_upgrade_outcomes.up.sql
• proto/sandbox/manager/v1/manager.proto

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[mabdelraouf-pplx]

Approved to unblock, with these follow-ups recorded before runtime-upgrade pods are enabled:

• In activate_once, revalidate through running_execution_for after activate_on_target and return that fresh response. Stop or suspend can finish between activation and the final check while retaining the pod identity, so returning the original response can expose a stale PID.
• Retain the new sandbox-manager SQLite migration in any rollback build. A plain commit revert removes an applied migration from the bundled catalog and prevents the older sandbox-manager from reopening the database.
• Add explicit capability negotiation before the shim sends the new stage_from and checkpoint_local_artifact_id semantics. This prevents a newer shim paired with an older sandbox-manager from acting on a stale suspended copy during a partial rollout or rollback.
• Bind memory-loss consent to the recorded operation identity so a rolled-back operation cannot later be retried under the same operation and authorization IDs with changed consent.

The first two are correctness/rollback issues; the latter two are rollout and idempotency hardening for the dependent API enablement.

[coderabbitai]

Actionable comments posted: 1

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Inline comments:
Review comments at @proto/sandbox/manager/v1/manager.proto:
- Around line 1293-1302: Update the `activation_claimed` field comment to say
the operation claimed its activation rather than completed it. Clarify that a
claimed start is recorded before execution and may fail, and that pod status
indicates whether the sandbox is running; preserve the distinction that an
already-running execution also counts as a claim.

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• Repository: perplexityai/SPACE
• Branch: gigi/pla-7337-shim-runtime-upgrade-checkpoint
• File: .coderabbit.yaml
• Commit: d1a1b41
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Commits

Reviewing files that changed from the base of the PR and between 5d19b2c and d1a1b41.

Files ignored due to path filters: 5

• crates/libs/common/core/src/fixtures/sandbox_pod_restore_runtime_upgrade_started.snap is excluded by !**/*.snap
• crates/libs/common/core/src/fixtures/sandbox_pod_restore_runtime_upgrade_stopped.snap is excluded by !**/*.snap
• crates/libs/common/core/src/fixtures/sandbox_pod_restore_runtime_upgrade_suspended.snap is excluded by !**/*.snap
• shim/proto/sandbox/manager/v1/manager.pb.go is excluded by !**/*.pb.go, !**/*.pb.go
• shim/proto/sandbox/manager/v1/manager_grpc.pb.go is excluded by !**/*.pb.go, !**/*.pb.go

Files selected for processing: 10

• crates/l30_storage/sbx/mgr/store/src/db/runtime_upgrades.rs
• crates/l30_storage/sbx/mgr/store/src/db/runtime_upgrades/tests.rs
• crates/l40_api/api/src/controllers/sandbox/lifecycle/characterization_tests.rs
• crates/l40_api/sbx/mgr/server/src/service/runtime_upgrade/rpc.rs
• crates/l40_api/sbx/mgr/server/src/service/runtime_upgrade/rpc/tests.rs
• crates/test_support/node/api/sim/src/worker.rs
• db/sandbox-manager/20261102233341_sandbox_runtime_upgrade_outcomes.up.sql
• docs/execution-environments.md
• proto/sandbox/manager/v1/manager.proto
• shim/space.go

Files skipped from review as they are similar to previous changes: 1

• shim/space.go

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[the-gigi-pplx]

@mabdelraouf-pplx Thanks. All four are handled:

1. activate_once now answers through answer_after_activation, which re-reads the row and goes through running_execution_for, so the pod gets the live runtime's response or a refusal, never the start's own pid. an_activation_in_place_answers_only_a_sandbox_still_running_the_pods_execution covers a row stopped or suspended after the start with the pod's identity still on it, and a started row whose runtime is gone; both are refused. The harness can't launch, so it drives the answer directly rather than through a successful start.
2. Rollback: the PR body and docs/execution-environments.md now say a rollback build reverts the code but keeps the sandbox_runtime_upgrade_outcomes migration (its files and its entry in the store's migration list), as db/README.md requires of any binary rollback. The table only adds rows and nothing older reads it.
3. and 4. Capability negotiation and binding memory-loss consent to the recorded operation are recorded for the api half (PR [api] trigger a stopped sandbox's runtime upgrade from a test hook, and smoke it on Kind #1322), to land before it renders these pods. The PR body lists both under "Not covered".