THE ASSET HUB MIGRATION (Please Review) by ggwpez · Pull Request #856 · polkadot-fellows/runtimes

ggwpez · 2025-08-18T12:46:03Z

A high-level look of the migration is this:

You can see the main components being the pallet_rc_migrator and pallet_ah_migrator. The RC migrator pallet takes data out of the RC storage and enqueues it for AH through XCM::Transact calls to the AH migrator pallet.
Each pallet on the RC side has a migrator module that handles the removal of the old data and creation of the messages for AH. AH then processes these messages through the MQ pallet and acknowledges back to RC that they were processed (not shown in the graphic).

There is rate-limiting code in place to prevent it from overloading the DMP queue or Asset Hub.

For Reviewers

The review comments are being addressed in #915.
We need eyes on the Core part that is described below.

Core STM

The main stage transitions look like this. The only manual part is the scheduling call by the fellowship that kicks off the procedure:

Pending wait for Fellowship to call schedule_migration(when) -> Scheduled
Scheduled waiting for scheduled block -> WaitingForAH
WaitingForAH AH replies that it is ready -> WarmUp
WarmUp waiting for warm-up end -> Starting
Starting doing some startup initialization -> DataMigration
DataMigration MAIN PART all pallet migrations finish -> CoolOff
CoolOff waiting for cool-off to end -> SignalMigrationFinish
SignalMigrationFinish send signal to AH that we are done -> MigrationDone
MigrationDone finished, unlock all Pallets.

State Machine

The core State Machine lives in the RcMigrator pallet in its on_initialize:

runtimes/pallets/rc-migrator/src/lib.rs

Lines 1338 to 1342 in 8ef1cc7

    
           match stage { 
        
           	MigrationStage::Pending | MigrationStage::MigrationPaused { .. } => { 
        
           		return weight_counter.consumed(); 
        
           	}, 
        
           	MigrationStage::Scheduled { start } => {

On each block the Rc Migrator checks the current state and possibly progresses to the next one. It will only do a single state transition per block to reduce complexity of the code. Generally, there are three states per pallet (called stages in the code). Some pallets have more then three, but it is generally still a multiple of three and always follows the pattern of PalletInit, PalletOngoing { cursor }, PalletDone:

runtimes/pallets/rc-migrator/src/lib.rs

Lines 239 to 244 in 8ef1cc7

    
           	MultisigMigrationInit, 
        
           	MultisigMigrationOngoing { 
        
           		/// Last migrated key of the `Multisigs` double map. 
        
           		last_key: Option<(AccountId, [u8; 32])>, 
        
           	}, 
        
           	MultisigMigrationDone,

Each pallet then has one migrator struct (eg. MultisigMigrator<T>) that migrates the storage items from the Relay side. It lives in the module of its name rc-migrator/src/multisig.rs respectively.
Taking Multisigs as an example; you can find two functions in the migrator struct: migrate_many and migrate_single. The former one is from the PalletMigration trait. The migrate_single function is done by convention to keep the code readable. The migrate_many does the following:

Weight accounting for the RC side: Normal weight tracking to not have overtime RC blocks
Weight accounting for the AH side: Ensuring to not send messages that would take up too much weight on AH processing
Ensure that DMP messages are sensibly sized by using the XcmBatchAndMeter
Taking the data out from the Relay chain (deleting it)
Including the data into a DMP message and sending it towards AH

AH Side

The main logic on Asset Hub lives in the AhMigrator pallet. It contains at least one extrinsic per pallet to receive the incoming data from the RC. We are using extrinsics since RC is wrapping the data into XCM::Transacts:

runtimes/pallets/ah-migrator/src/lib.rs

Lines 650 to 653 in 9a20b12

    
           pub fn receive_multisigs( 
        
           	origin: OriginFor<T>, 
        
           	accounts: Vec<RcMultisigOf<T>>, 
        
           ) -> DispatchResult {

This calls into the multisig module to integrate the data into the storage. Per convention we are emitting events for each item and the whole batch.
The main task of the AH side is to integrate the data. In the example of the multisig it is special since we do not migrate the multisig, but only the reserved account which will be unreserved on AH.

Messaging Logic

The messaging is ACK based. The Relay sends message to Asset Hub up to a specified limit (50). The limit can be adjusted on the fly through a dedicated dispatchable call, restricted to Admin and Manager roles. The limit may be overstepped by the configured batch-size (10), so in total there should never be more than 60 DMPs queued. Each DMP is set to at most 50KB.

The Relay Chain migrator creates a query for each XCM data message using the XCM query–response primitives and attaches a response status request from Asset Hub to the message. The XCM executor on Asset Hub then sends back the response status for every message with such a request.

The Relay migrator stores each data message sent to Asset Hub until it receives confirmation of successful processing. It also provides a dispatchable call, available only to Admin and Manager roles, to resend any unconfirmed messages.

A bug that prevented certain messages from being accounted for during a particulat pallet migration caused the Westend AHM stall. The system was queuing too many DMPs, which forced WAH to author an overweight block while attempting to process them all at once.

Call Filtering

Pallet calls are filtered during the migration for three reasons:

prevent malicious users from spamming the chain with cheap TX and slowing down the migration
prevent users from sending many UMPs out of AH to clog up the UMP queue
prevent interference with pallets that are being migrated to avoid messing up their storage invariants

Both RC and AH provide call filters for Before, During and After the migration. As you can see, most things are disabled during the migration on both chains. After the migration, Relay chain keeps pretty much everything disabled since it was now enabled on AH:

Before: RC everything enabled, AH all new pallets disabled (staking, gov etc)
During: RC mostly everything disabled, AH mostly everything disabled
After: RC mostly everything disabled (staking, gov etc), AH everything enabled (staking, gov etc)

This is implemented by returning three bools, one for each phase:

runtimes/system-parachains/asset-hubs/asset-hub-polkadot/src/ah_migration/call_filter.rs

Lines 81 to 83 in 88f4aaf

    
           pub fn call_allowed_status( 
        
           	call: &<Runtime as frame_system::Config>::RuntimeCall, 
        
           ) -> (bool, bool, bool) {

Testing and Dry-Runs

https://github.com/paritytech/ahm-dryrun is the repository for testing infrastructure for AHM. As of now, the following is being tested there (as a part of "AHM Flow (all steps)" nightly action):

Dry-running a migration on a fork of Kusama
Re-running the rust unit tests introduced in this branch
Re-running a subset of the same tests, re-written in TS
Re-running PET tests.

Each action produces a table with the summary of the test results:

And 4 snapshot files (2 real databases, 2 try-runtime snapshots) which can be used to re-run any of the tests, or run the pre/post migration chain, locally.

Full Changelog

[AHM] OpenGov for Kusama AH ([AHM] OpenGov for Kusama AH #877)
Relay Chain Accounts to Asset Hub Migration (Relay Chain Accounts to Asset Hub Migration #515)
Test Relay<->AH migration through DMP messages (Test Relay<->AH migration through DMP messages #528)
[AHM] Improve account migration ([AHM] Improve account migration #532)
[AHM] Add multisig migration ([AHM] Add multisig migration #534)
[AHM] Proxy migration ([AHM] Proxy migration #542)
[AHM] Cleanup and add Preimage doc ([AHM] Cleanup and add Preimage doc #543)
[AHM] Improve accounts migration ([AHM] Improve accounts migration #550)
[AHM] Preimage migration ([AHM] Preimage migration #545)
[AHM] Add Polkadot call filtering ([AHM] Add Polkadot call filtering #559)
[AHM] Nomination pools ([AHM] Nomination pools #562)
[AHM] referenda pallet ([AHM] referenda pallet #558)
[AHM] Cleanup ([AHM] Cleanup #565)
[AHM] Scheduler Pallet ([AHM] Scheduler Pallet #569)
[AHM] Fast unstake and Bags list ([AHM] Fast unstake and Bags list #563)
[AHM] Pallet claims ([AHM] Pallet claims #570)
[AHM] Conviction Voting Pallet ([AHM] Conviction Voting Pallet #578)
[AHM] Pallet Indices ([AHM] Pallet Indices #577)
[AHM] pause scheduler during migration ([AHM] pause scheduler during migration #580)
[AHM] Asset rate pallet migration ([AHM] Asset rate pallet migration #581)
[AHM] Bounties data migration ([AHM] Bounties data migration #585)
[AHM] Vesting ([AHM] Vesting #575)
[AHM] fix the rc-migrator call filter ([AHM] fix the rc-migrator call filter #598)
[AHM] Sovereign Account Translation ([AHM] Sovereign Account Translation #594)
[AHM] Crowdloans ([AHM] Crowdloans #592)
[AHM] Set up AH migration testing framework for single pallets ([AHM] Set up AH migration testing framework for single pallets #597)
[AHM] Stage management ([AHM] Stage management #584)
[AHM] Do not pause inherents 🙈 ([AHM] Do not pause inherents 🙈 #609)
[AHM] Relay Chain accounts' reserves ([AHM] Relay Chain accounts' reserves #602)
[AHM] Benchmarks ([AHM] Benchmarks #589)
[AHM] Pallet testing framework ([AHM] Pallet testing framework #612)
[AHM] fix xcm weight at most ([AHM] fix xcm weight at most #617)
[AHM] Improve weight accounting for accounts migration ([AHM] Improve weight accounting for accounts migration #618)
[AHM] AH acks messages from RC ([AHM] AH acks messages from RC #620)
[AHM] Pure Proxy Investigation ([AHM] Pure Proxy Investigation #621)
[AHM] Remove migrated items for pallet preimage and improve testing ([AHM] Remove migrated items for pallet preimage and improve testing #619)
[AHM] Referenda metadata ([AHM] Referenda metadata #633)
[AHM] Fix accounts migration failures ([AHM] Fix accounts migration failures #628)
[AHM] refactor events and enable scheduled migration start ([AHM] refactor events and enable scheduled migration start #634)
[AHM] Migrating DOT total issuance tracking from RC to AH ([AHM] Migrating DOT total issuance tracking from RC to AH #607)
[AHM] Comment faulty checks out ([AHM] Comment faulty checks out #640)
Account migrator refactor (Account migrator refactor #639)
[AHM] Rebase ([AHM] Rebase #641)
[AHM] Run AHM test in CI ([AHM] Run AHM test in CI #642)
[AHM] Vesting test ([AHM] Vesting test #615)
[AHM] bags_list and conviction_voting tests ([AHM] bags_list and conviction_voting tests #632)
[AHM] Treasury pallet migration ([AHM] Treasury pallet migration #624)
[AHM] Fix tests for pallet preimage ([AHM] Fix tests for pallet preimage #643)
[AHM] Test Coverage Report ([AHM] Test Coverage Report #650)
[AHM] deactivate/reactivate total issuance & weights ([AHM] deactivate/reactivate total issuance & weights #648)
[AHM] add sudo behind feature flag ([AHM] add sudo behind feature flag #657)
[AHM] fast_unstake tests ([AHM] fast_unstake tests #658)
[AHM] asset_rate test ([AHM] asset_rate test #660)
[AHM] Pallet treasury tests ([AHM] Pallet treasury tests #664)
[AHM] Improve account balances integration tests ([AHM] Improve account balances integration tests #655)
[AHM] Integrate AH migrator weights to RC ([AHM] Integrate AH migrator weights to RC #665)
Testing for bounties migration (Testing for bounties migration #669)
[AHM] Westend port adapters ([AHM] Westend port adapters #652)
[AHM] fix checking account and total issuance migration ([AHM] fix checking account and total issuance migration #636)
[AHM] Bump polkadot relay and AH versions ([AHM] Bump polkadot relay and AH versions #667)
[AHM] Fix tests for pallet treasury ([AHM] Fix tests for pallet treasury #671)
[AHM] Claims and Crowdloan tests ([AHM] Claims and Crowdloan tests #622)
[AHM] Benchmarks ([AHM] Benchmarks #663)
[AHM] Add Asset Hub CallFilter ([AHM] Add Asset Hub CallFilter #670)
[AHM] Westend staking migration ([AHM] Westend staking migration #689)
[AHM] Referenda migration storage checks ([AHM] Referenda migration storage checks #672)
[AHM] AH benchmarks cleanup ([AHM] AH benchmarks cleanup #690)
[AHM] Westend Async Staking Migration ([AHM] Westend Async Staking Migration #691)
[AHM] Relay Chain migrator benchmarks ([AHM] Relay Chain migrator benchmarks #692)
[AHM] Asset Hub ops pallet benchmarks ([AHM] Asset Hub ops pallet benchmarks #693)
[AHM] Xcm send weights and Batch helper types ([AHM] Xcm send weights and Batch helper types #694)
Finish staking Westend (Finish staking Westend #695)
[AHM] Account provider/consumer references ([AHM] Account provider/consumer references #702)
[AHM] Fix westend builds ([AHM] Fix westend builds #704)
[AHM] Generate weights ([AHM] Generate weights #706)
[AHM] Proxy fixes and more tests ([AHM] Proxy fixes and more tests #707)
[AHM] Docs and simpler events ([AHM] Docs and simpler events #699)
[AHM] Test call decoding ([AHM] Test call decoding #710)
[AHM] Emulated test for migration with async backing ([AHM] Emulated test for migration with async backing #717)
[AHM] Increase test coverage ([AHM] Increase test coverage #720)
[AHM] Add referenda checks to Westend migration ([AHM] Add referenda checks to Westend migration #713)
[AHM] Nom_pools test ([AHM] Nom_pools test #677)
[AHM] Scheduler storage item checks ([AHM] Scheduler storage item checks #680)
[AHM] Update Polkadot Snapshot ([AHM] Update Polkadot Snapshot #725)
[AHM] Pallet multisig tests ([AHM] Pallet multisig tests #666)
[AHM] Adapt XCM configuration to account for changes before and after migration ([AHM] Adapt XCM configuration to account for changes before and after migration #722)
[AHM] document checking account migration ([AHM] document checking account migration #716)
[AHM] Dependency fixes for integration tests and the Polkadot runtime ([AHM] Dependency fixes for integration tests and the Polkadot runtime #751)
[AHM] Remove empty conviction voting filter ([AHM] Remove empty conviction voting filter #750)
[AHM] Missing TODOs and AccountState type update ([AHM] Missing TODOs and AccountState type update #742)
[AHM] DMP prioritization on AH ([AHM] DMP prioritization on AH #772)
[AHM] Disable #[pallet::hooks] for migrating pallets during migration ([AHM] Disable #[pallet::hooks] for migrating pallets during migration #784)
[AHM] AH messages prioritization on RC ([AHM] AH messages prioritization on RC #787)
[AHM] Cache test snapshots and include more tests into CI job ([AHM] Cache test snapshots and include more tests into CI job #788)
[AHM] Cleanup Westend feature ([AHM] Cleanup Westend feature #789)
[AHM] Introducing the Cool-Off stage ([AHM] Introducing the Cool-Off stage #786)
[AHM] Flow Control System ([AHM] Flow Control System #780)
[AHM] Migrate pallet delegated-staking to AH ([AHM] Migrate pallet delegated-staking to AH #791)
[AHM] Merge master into dev branch ([AHM] Merge master into dev branch #793)
[AHM] Disable indirect XCMs from RC to AH and vice versa during migration ([AHM] Disable indirect XCMs from RC to AH and vice versa during migration #774)
Rebase
bring back RelayTreasuryLocation to make old tests compiole
[AHM] Missing RootLocation for WaivedLocation for AHP ([AHM] Missing RootLocation for WaivedLocation for AHP #798)
[AHM] Missing SecretaryEntities for AHP ([AHM] Missing SecretaryEntities for AHP #797)
[AHM] Migration idempotency ([AHM] Migration idempotency #808)
[AHM] Block number providers for migrating pallets ([AHM] Block number providers for migrating pallets #809)
[AHM] Copy latest ah-ops pallet from the SDK ([AHM] Copy latest ah-ops pallet from the SDK #810)
[AHM / ah-migrator]: Implement RC->AH account translation mocked migration across all involved pallets ([AHM / ah-migrator]: Implement RC->AH account translation mocked migration across all involved pallets #807)
[AHM] Complete account balances tests ([AHM] Complete account balances tests #674)
[AHM] Address TODOs ([AHM] Address TODOs #815)
[AHM] Async staking config ([AHM] Async staking config #812)
[AHM] Optional migration manager account id ([AHM] Optional migration manager account id #818)
[AHM] Type safe Hold and Freeze-Reason translation ([AHM] Type safe Hold and Freeze-Reason translation #819)
[AHM] Create new response query on resend and tests ([AHM] Create new response query on resend and tests #816)
PolkadotAssetHub: Enable Async Backing (PolkadotAssetHub: Enable Async Backing #763)
Ensure no era planned when migration starts (Ensure no era planned when migration starts #728)
[AHM] with async backing ([AHM] with async backing #822)
[AHM] Staking migration ([AHM] Staking migration #821)
identify with only validator account
[AHM] Tests work for Paseo ([AHM] Tests work for Paseo #827)
[AHM] Child bounties ([AHM] Child bounties #613)
[AHM] Cleanup and linter fixes ([AHM] Cleanup and linter fixes #828)
[AHM] Fix snowbridge test - wrong import of RelayTreasuryPalletAccount (instead of AH, it should be BH) ([AHM] Fix snowbridge test - wrong import of RelayTreasuryPalletAccount (instead of AH, it should be BH) #831)
[AHM] Account Translation mapping ([AHM] Account Translation mapping #829)
Fast unstake: remove alias
fmt
[AHM] Max migrated items per block ([AHM] Max migrated items per block #834)
[AHM] Record migration timings ([AHM] Record migration timings #835)
[AHM] Remove storage aliases and cleanup ([AHM] Remove storage aliases and cleanup #832)
[AHM] fix Kusama bags list pallet benchmarks ([AHM] fix Kusama bags list pallet benchmarks #836)
[AHM] Unprocessed msg buffer size 50 ([AHM] Unprocessed msg buffer size 50 #839)
[AHM] Post migration cool off stage ([AHM] Post migration cool off stage #841)
[AHM] Multisig test and storage_alias cleanup ([AHM] Multisig test and storage_alias cleanup #842)
[AHM] Remove fast-unstake and test fixes ([AHM] Remove fast-unstake and test fixes #846)
Run try-state check for all pallets post AHM rust tests (Run try-state check for all pallets post AHM rust tests #833)
[AHM] Preserve on RC manager' account ([AHM] Preserve on RC manager' account #843)
[AHM] Filter staking calls before migration starts ([AHM] Filter staking calls before migration starts #847)
[AHM] State Decode Tests ([AHM] State Decode Tests #848)
[AHM] Send xcm extrinsic within migrator pallets ([AHM] Send xcm extrinsic within migrator pallets #851)
Merge and cleanup merge commit
[AHM] Call filter configuration #845
Improve Era Scheduling #852
[AHM] Integrate migration for Kusama #862
[AHM] Society pallet migration #875
[AHM] Fix derived account translation script #872
[AHM] OpenGov for Kusama AH #877
[AHM] OpenGov for Polkadot AH tweaks #626
[AHM] Free 'Any' proxies for pure accounts #879
[AHM] VRF randomness falls back to RC state root #885
[AHM] Society pallet version upgrade and new storage values migration #886
[AHM] Canceller can stop migration #882
[AHM] Final Staking Configs for Kusama #883
[AHM] Migrate Pallet Recovery #854
[AHM] Tweaks, TODOs and nits #888
AHM: staking async bump #895
Removed unused update_ah_msg_processed_count (or missing benchmark?) #892
[AHM] Max data messages per block limit #896
[AHM] Staking Account Translation #889

// only to let all CIs to execute for now

Does not require a CHANGELOG entry

This PR is not intended to be merged into the master branch but into a dedicated Asset Hub migration working branch. Please create such a branch if you have the necessary permissions and change the base for this PR. The PR introduces two pallets designed for the Asset Hub migration, Relay Chain migrator (rc-migrator) and Asset Hub migrator (ah-migrator). Please refer to the code base for more docs. Currently, these pallets handle only the migration of Relay Chain accounts. They are intended to support the migration of all migrating pallets and act as managers for the overall migration process. It might be helpful to merge this PR into the dev branch to use this initial setup as a base for further development. [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

To be merged into the AHM dev branch. Changes: - Create `polkadot-integration-tests-ahm` crate that pulls in the Relay and AH runtimes - Load snapshot for both chains and run trivial DMP testing - Add stage to initialize the account migration - TODO: Investigate failing debug assertion on the account migration - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

👉 To be merged into the AHM working branch. Changes: - Clean up AH and RC account migration code - Add error logging - Mint Relay blocks until no more account can be moved - Mint AH blocks until all DMP messages are consumed - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

👉 To be merged into the AHM working branch. Changes: - Add Multisig module to Relay and AH - Migrate multisigs out (TODO investigate weird accs with ggwpez/pdu#5) - Unlock deposits on the AH side since we dont actually migrate multisigs since they contain a call hash, making them impossible to migrate. - TODO docs - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

👉 To be merged into the AHM dev branch. quote from the `proxy.md` doc: ## Pallet Proxy The proxy pallet consists of two storage variables. ## Storage: Proxies The [Proxies](https://github.com/paritytech/polkadot-sdk/blob/7c5224cb01710d0c14c87bf3463cc79e49b3e7b5/substrate/frame/proxy/src/lib.rs#L564-L579) storage map maps a delegator to its delegates. It can be translated one-to-one by mapping the `ProxyType` and `Delay` fields. ### Proxy Type Translation The different kinds that are possible for a proxy are a [runtime injected type](https://github.com/paritytech/polkadot-sdk/blob/7c5224cb01710d0c14c87bf3463cc79e49b3e7b5/substrate/frame/proxy/src/lib.rs#L119-L125). Since these are different for each runtime, we need a converter that maps the Relay to AH `ProxyType` as close as possible to keep the original intention. The Relay kind is defined [here](https://github.com/polkadot-fellows/runtimes/blob/dde99603d7dbd6b8bf541d57eb30d9c07a4fce32/relay/polkadot/src/lib.rs#L1000-L1010) and the AH version [here](https://github.com/polkadot-fellows/runtimes/blob/fd8d0c23d83a7b512e721b1fde2ba3737a3478d5/system-parachains/asset-hubs/asset-hub-polkadot/src/lib.rs#L453-L468). This is done by injecting a `RcToProxyType` converter into the Asset Hub migration pallet. This is not bullet proof since it relies on some copy&paste code instead of pulling in the Polkadot runtime into the AH runtime but it is the simplest solution. Mapping from Relay to AH looks as follows: - Any: same - NonTransfer: same - Governance: newly added - Staking: newly added - Variant 4: ignore as it is a historic remnant - Variant 5: ignore ditto - CancelProxy: same - Auction: dropped - NominationPools: newly added All variants that serve no purpose anymore on the Relay Chain are deleted from there. For example `Staking`. The ones that are still usable on the relay like `NonTransfer` are **also deleted** since there is no storage deposit taken anymore. (TODO think about what is best here) ### Translation of the Delay The [delay of a ProxyDefinition](https://github.com/paritytech/polkadot-sdk/blob/7c5224cb01710d0c14c87bf3463cc79e49b3e7b5/substrate/frame/proxy/src/lib.rs#L77) is measured in blocks. These are currently 6 seconds Relay blocks. To translate them to 12s AH blocks, we can divide the number by two. ## Storage: Announcements The [Announcements](https://github.com/paritytech/polkadot-sdk/blob/7c5224cb01710d0c14c87bf3463cc79e49b3e7b5/substrate/frame/proxy/src/lib.rs#L581-L592) storage maps proxy account IDs to [Accouncement](https://github.com/paritytech/polkadot-sdk/blob/7c5224cb01710d0c14c87bf3463cc79e49b3e7b5/substrate/frame/proxy/src/lib.rs#L80-L89). Since an announcement contains a call hash, we cannot translate them for the same reason as with the Multisigs; the preimage of the hash would be either undecodable, decode to something else (security issue) or accidentally decode to the same thing. We therefore do not migrate the announcements. ## User Impact - Announcements need to be re-created - Proxies of type `Auction` are not migrated and need to be re-created on the Relay - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

👉 To be merged into the Asset Hub Migration working branch. Changes: - Factor out XCM sending into common function - Cleanup - Add docs for the preimage pallet that I started with - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

Meant to be merged into `dev-asset-hub-migration` branch. Some improvements and fixes to the accounts migration.

👉 To be merged into the AHM dev branch. quote from Preimage.md: The preimage pallet consists of three storage maps, one of which is a legacy item. The interesting one are `RequestStatusFor` and `PreimageFor`. ## Storage: PreimageFor [Maps](https://github.com/paritytech/polkadot-sdk/blob/00946b10ab18331f959f5cbced7c433b6132b1cb/substrate/frame/preimage/src/lib.rs#L185) a hash and the length of a preimage to its preimage data. Preimages can be migrated rather easily by sending them in chunks from the Relay and appending them on the Asset Hub. The preimages are often used to store large governance calls. Q: One question here would be whether or not we want to translate these calls. I think we can and should. But I am not sure about the best time point to do so. We can translate the preimages calls upon arrival on the Asset Hub, although there is a small chance that a preimage that was not intended to be decoded as a call would be translated. After all, the preimage pallet is a universal data storage without any implied semantics about its content. It could therefore be better to translate the preimages once we are migrating the Referenda pallet and then only translate all preimages that occur as hash lookups in a referenda. However, since the scheduler is the only way to request a preimage, all requested preimages should probably be valid calls. But the translation still needs to happen in accord with the Referenda pallet as to not invalidate its hashes. Basically: loop referenda -> load referenda -> load preimage of referenda -> translate preimage -> calculate new preimage hash -> update preimage with new hash -> update referenda with new hash. One further note on the preimage translation: If the length of a preimage is increased by the translation, then we should not reconsider the deposit but keep the original deposit as to not punish users for this. The cases that the translation increases the size of a preimage past the 4MiB hard limit should be negligible. ## Storage: RequestStatusFor This maps preimage hashes to [RequestStatus](https://github.com/paritytech/polkadot-sdk/blob/00946b10ab18331f959f5cbced7c433b6132b1cb/substrate/frame/preimage/src/lib.rs#L81-L89). The RequestStatus contains a consideration that will be re-considered upon import. This would unreserve funds for all users that noted preimages. Possible up to 20 DOT per preimage. The migration of this should be straighforward this but we need to remember that it must be updated if we start translating preimage calls. ## Storage: StatusFor Deprecated. Will not be migrated but funds will be unreserved. ## User Impact For anyone who has registered a preimage: - If the preimage was in the new RequestStatusFor: Some unlocked funds 😎. We cannot calculate a list of affected accounts in advance since users can still influence this. - If the preimage was in the old StatusFor: will be removed and funds unlocked. [Exhaustive list](https://github.com/ggwpez/substrate-scripts/blob/master/ahm-preimage-statusfor-accounts.py) of all 166 Polkadot accounts that are affected by this and will have **UP TO** these funds unlocked (not a legally binding statement): <details><summary>Details</summary> <p> - `16LKv69ct6xDzSiUjuz154vCg62dkyysektHFCeJe85xb6X`: 1256.897 DOT - `15ynbcMgPf7HbQErRz66RDLMuBVdcWVuURhR4SLPiqa6B8jx`: 633.121 DOT - `12jW7jTPVKWahgRvxZL8ZCKKAwzy4kbrkHhzhafNjHEJXfw9`: 633.121 DOT - `13BD4q9RYQtxkUQLvyCksnN9Pa7sC5fGj5dcdxpojxGkoHMp`: 40.229 DOT - `13NRkBCD7NLkppxoHpYrUQ6GcjNpZEWCeXFjXDgDctANBG9j`: 40.193 DOT - `14VwUiNPMN2T9jGvWaSm5pwcUr5ziqLjTomRm6xUxwy3Urjm`: 40.17 DOT - `14TBcRgp166DXvMv9ZCJbKSqanUGP6tguryPQcaBqjQp8d4m`: 40.152 DOT - `14TBcRgp166DXvMv9ZCJbKSqanUGP6tguryPQcaBqjQp8d4m`: 40.143 DOT - `1eK9SC7Z2QFi4es2aKQHAehcZqY7bEiprkpsT483PvVK8KE`: 40.143 DOT - `15YLDvV6Q2NUVEFBN26kRgHyyeH1Bu91NKTwBg3xW3hEVfoj`: 40.108 DOT - `13q3NEbcSepgVbCyN6XLQtEvyZuAEqDUPLiuX2iydaQrwDCU`: 40.107 DOT - `14M94kYk31k2hY8MpnfNPRviJ4VcsFFjBhq7V2Fs9DzCVhXc`: 40.107 DOT - `1316cTZeHz8HtEjaJRHu8sHbp9brtUmy2LiP74KZXgXhifry`: 40.107 DOT - `16maYYXg9chsfsBVoiSbSWzmFveamERwShPZv3SB5hVnYTmT`: 40.107 DOT - `12ow3eJ3vbjeNRahUUrBnc98mWeJTSQ7rJCAVqiFQDEnzbu8`: 40.107 DOT - `13g4yRs3NbtaXyu1Uww8AXd4uvrqXyR1hPR4jejRLv8rBUyB`: 40.107 DOT - `12rpF7eUC59kU7itRe3NpSTQJroK5YiHfn5c4bT21BZxp257`: 40.107 DOT - `16maYYXg9chsfsBVoiSbSWzmFveamERwShPZv3SB5hVnYTmT`: 40.107 DOT - `1fN87Fgj5BUhezFgbLiGbXTMrBVggnmYBX9anzMBky8KaJ5`: 40.107 DOT - `14PiQ7uar36zPMgEckA7qWUahYheavRL6NHCbUCkXXRNrFSc`: 40.107 DOT - `13SceNt2ELz3ti4rnQbY1snpYH4XE4fLFsW8ph9rpwJd6HFC`: 40.107 DOT - `1hzs7HJ4teyvX9cwFsxCaJBSNQcPAWHixQT4fem5h66cogb`: 40.107 DOT - `15ho9t317QDvod18gCoTNe9yoiMjTXHwVxd5RC2iWyzEEby1`: 40.107 DOT - `13SceNt2ELz3ti4rnQbY1snpYH4XE4fLFsW8ph9rpwJd6HFC`: 40.107 DOT - `12bMyzdtiT2V9iNJ7BzQXPmzZ4KTzqFmZPSNeBmg97mFP5F4`: 40.107 DOT - `1QjuTEKebQ3au8bxQC6iwYSPCA2iZn3YHwX8VABCauKtwRk`: 40.107 DOT - `15fvwi77dujPz9Mk9U792gNa2Mg5z6489DPwErwCZwu7EpLE`: 40.107 DOT - `1WgB9o954mkQi97f36azSwDt7SfRUQuJ1kCyb7Sv1WAUcSe`: 40.107 DOT - `14zU4FXuYU2wmi2PfXLADZW92NRYEw8nfUEvi7sqiJLafJ3A`: 40.107 DOT - `15cfSaBcTxNr8rV59cbhdMNCRagFr3GE6B3zZRsCp4QHHKPu`: 40.107 DOT - `133VgJJgp1s9wxLqgCFxYx6T873hZQNchJM9tmbU6NkYaaqW`: 40.107 DOT - `13YMTEPKAxPRiyaZdMKrozeNT9x1Pa5h7aExebCdi6nc3Qqd`: 40.107 DOT - `14M94kYk31k2hY8MpnfNPRviJ4VcsFFjBhq7V2Fs9DzCVhXc`: 40.107 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.107 DOT - `15cfSaBcTxNr8rV59cbhdMNCRagFr3GE6B3zZRsCp4QHHKPu`: 40.107 DOT - `15qz4ZLeyXp1i4Jbx7AXiUQVCCLWVXu3dLjcTPHY3v9KGAvL`: 40.107 DOT - `14TBcRgp166DXvMv9ZCJbKSqanUGP6tguryPQcaBqjQp8d4m`: 40.107 DOT - `13zTcqasJT4DnDgNjmsceACcuSjt4q2geEjtMprnGXCnuuh1`: 40.107 DOT - `12eWtdVxQ9ScYD9AzyMuSsX8B9iEikWtUGiirJ1YJtDCCuwu`: 40.107 DOT - `1342Xpqiwwmxnhugnp91d21xR7s8V6uxXQJ1xYBQfUwbvgDB`: 40.107 DOT - `16JA2pWJ7rXhKAq9xaCpSvVgWf6MaPLYvtSVpj7ZWjTkhYoB`: 40.107 DOT - `1j5YyEGdcPd9BxkzVNNjKkqdi5f7g3Dd7JMgaGUhsMrZ6dZ`: 40.107 DOT - `1njGozmydXftj6KYFPGLPN7Qq3kgmFqxsRdF5hWJAschp1S`: 40.107 DOT - `12pdBf9NJ2jqRHdVmtqSZMRvWQoiH81AfaACgiMuXLeySNzc`: 40.107 DOT - `1njGozmydXftj6KYFPGLPN7Qq3kgmFqxsRdF5hWJAschp1S`: 40.107 DOT - `16MF8p8KfktKazPiQEqTXJq1CtYuZ9aNrBShXQNRdhckctC5`: 40.107 DOT - `197nLd2rFoesjmvTfMpkFhHde7ngKzpLaA8xsbdWyeaJwzx`: 40.107 DOT - `12BYYgmRb5BjHjZf7nykJDB1C6FXTfqr9QSmrav8RHt19ahj`: 40.107 DOT - `12BJTP99gUerdvBhPobiTvrWwRaj1i5eFHN9qx51JWgrBtmv`: 40.107 DOT - `1333zsMafds2sKAr8nG3zwXTCHPYv2Nm6CRgakpu6YVGt7nM`: 40.107 DOT - `15qz4ZLeyXp1i4Jbx7AXiUQVCCLWVXu3dLjcTPHY3v9KGAvL`: 40.107 DOT - `13EDmaUe89xXocPppFmuoAZaCsckaJy3deAyVyiykk1zKQbF`: 40.107 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.107 DOT - `1ZVYsze5Ls3osofU6wWSp5dphr62Rj7YiL4NsXiZU3a298F`: 40.107 DOT - `14j9cWtbvYid754crk6ieQABGYHtGZozzeavT1jc11bt32ZM`: 40.107 DOT - `14fcqMPHhCtwnbPAHxjsf3JiGsDuLQPGMpndrWawuiAiiCqE`: 40.107 DOT - `12dt664RtnYbeiR1D45CUPyHk1Ufv1NEHFXkuRLy47FktR31`: 40.107 DOT - `131JKfT9kNvKjp5NJY2jHZmb32wjbr6xDHuCt4zHapWVtDde`: 40.107 DOT - `15cfSaBcTxNr8rV59cbhdMNCRagFr3GE6B3zZRsCp4QHHKPu`: 40.107 DOT - `1f1wZcBaJrPHkBkzx2S7KXFbjtT7KMg7fDaV47P6157KRWo`: 40.107 DOT - `14Q5M6LWDVCPm47sVvz6M6YAEsEi5u3Rszh8z5eC2bhL9Upk`: 40.107 DOT - `1k5ddMCPuLbu9Hax12EdKRmPwGigUKQW1ab6tRAWPxKygRF`: 40.107 DOT - `15YLDvV6Q2NUVEFBN26kRgHyyeH1Bu91NKTwBg3xW3hEVfoj`: 40.107 DOT - `14fhPR28n9EHZitNyf6wjYZVBPwKgcgogVjJPTzvCcb8qi9G`: 40.107 DOT - `1RYjrCKUmvM8D9QDKCNbWJYUe49h6ZfkgXvEAtkHgvzxbGB`: 40.107 DOT - `15wznkm7fMaJLFaw7B8KrJWkNcWsDziyTKVjrpPhRLMyXsr5`: 40.107 DOT - `14PiQ7uar36zPMgEckA7qWUahYheavRL6NHCbUCkXXRNrFSc`: 40.107 DOT - `14cFTN4jFFiiL1qszmGKZjokAdNr4YSD7Gf5rhZRA62TrtMb`: 40.107 DOT - `12bqgqerfH21x5hv85AJ9AiNFWXVmBLDoCvmz78MD4fgEP7Y`: 40.107 DOT - `15oXzySe6tjF2MumHfUodH8pFQWjy2hraRmXUJXXMKKY6p3F`: 40.107 DOT - `1ZVYsze5Ls3osofU6wWSp5dphr62Rj7YiL4NsXiZU3a298F`: 40.107 DOT - `12NCX9ZK1z9fxBfRraD6L4V86EmPipSerHnPcsj1k4hSkszg`: 40.107 DOT - `126X27SbhrV19mBFawys3ovkyBS87SGfYwtwa8J2FjHrtbmA`: 40.106 DOT - `15DL1EU6TpGDvL8HCNNU2ZDZdbcDUPiHYr1DBHBerUWMkJnT`: 40.106 DOT - `1bqBkjrbVc6nFbpZ2oqnbEKAs99CYSf2XVAwtGVWBRxDvNY`: 40.106 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.106 DOT - `152wswWPnwr1uLxqyENaesqjFtJcMwLT3dmrpb7KNt1PZ1PX`: 40.106 DOT - `14M94kYk31k2hY8MpnfNPRviJ4VcsFFjBhq7V2Fs9DzCVhXc`: 40.106 DOT - `16kkgkzjyJZL91WaL6GAUJnTZjiaowZcFyHAs5GWCNVqJimJ`: 40.106 DOT - `14mZVYo7jy13aHTiNMQZJzsii5CPsVEaMQwLXTEMLzkmxKH2`: 40.106 DOT - `13uvpozMRF7PCGbgPutm852Jt58nNBVUPdMFEQg5m7d1w8J8`: 40.106 DOT - `15cfSaBcTxNr8rV59cbhdMNCRagFr3GE6B3zZRsCp4QHHKPu`: 40.106 DOT - `123jNGxHk9ZV7oVVhFWFtMghNpmnmmTWxSpNxf8TTKzmCSQ2`: 40.106 DOT - `16MJX8HEwhbJwN9LCKLymW812eD9N97c5EkRNVjWzhFTwhBN`: 40.106 DOT - `13uvpozMRF7PCGbgPutm852Jt58nNBVUPdMFEQg5m7d1w8J8`: 40.106 DOT - `14mg5GK7RoiafH7djdKgZKxKewuhj8ds19bqjioaEHR6WhQ4`: 40.106 DOT - `1pzhyYR9gLk3GmwRtQESLkJCUXazFsAESgcbTRLc9q9hNuy`: 40.106 DOT - `16ZhiPmAt65atW7uvNSqyK1qitQL4FQUvYz8yYXfV1EGwVP1`: 40.106 DOT - `15kgSF6oSMFeaN7xYAykihoyQFZLRu1cF5FaBdiSDHJ233H5`: 40.106 DOT - `1L3j12S8rmd5GvJsxzBQzFKypYX5yV2kLrPJhacUYVrLvus`: 40.106 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.106 DOT - `13mEX6UD8t4L8YfsUxE8QjYFDkfEkAg2QpKWqKEfg5gZw3et`: 40.106 DOT - `13uvpozMRF7PCGbgPutm852Jt58nNBVUPdMFEQg5m7d1w8J8`: 40.106 DOT - `16Q4cR5vHLkoNqtqCZcdeKnZhY9a8AiXZAtemRJmMCpeiu82`: 40.106 DOT - `133uT5bf5xz8xMkCmwVBWpeHjN4NyfvfqwdpXu2oZnn29kEG`: 40.106 DOT - `13mm8mjuALSbyvfjfso22eexuFwL4MqMrcw1w5To9L52yb5h`: 40.106 DOT - `16kkgkzjyJZL91WaL6GAUJnTZjiaowZcFyHAs5GWCNVqJimJ`: 40.106 DOT - `12mRyiCp9zdh1wEVW5gLLiFBxDPKks72rRXmSupyEK3VAMLf`: 40.106 DOT - `12mRyiCp9zdh1wEVW5gLLiFBxDPKks72rRXmSupyEK3VAMLf`: 40.106 DOT - `13mm8mjuALSbyvfjfso22eexuFwL4MqMrcw1w5To9L52yb5h`: 40.106 DOT - `167vWTbKWmJhWUitgP1hGRZfaActDyZufCVu6vqUzrhQ2pS3`: 40.106 DOT - `15V75NT7bvs9YuVF6NTJynpTCswRshzwvcqPJZoaEJsBVxHi`: 40.106 DOT - `15VgqbuZGdwrpGjKkJMA9nE2gqLMHyQpWmE7k6dc4fQdRMXa`: 40.106 DOT - `12eMZTAnXEsyedXmsB6jDVRnF9Mq8ZrhLefRGhxPE4JwrPAS`: 40.106 DOT - `121k35TZKEpoQeKURnEgt2zqWsyDKxUJkTFuwpZeLoSYUe7o`: 40.106 DOT - `14PiQ7uar36zPMgEckA7qWUahYheavRL6NHCbUCkXXRNrFSc`: 40.106 DOT - `16ad3ehm2XsVQbQgqYPxicRB5nGinQU9zEKiCJ7ZVhRN9CyG`: 40.106 DOT - `123LuJKS65HaBbLSdDS46ByeC7bvQwA1iUhTpmjigQAfUKpK`: 40.106 DOT - `1316cTZeHz8HtEjaJRHu8sHbp9brtUmy2LiP74KZXgXhifry`: 40.106 DOT - `1316cTZeHz8HtEjaJRHu8sHbp9brtUmy2LiP74KZXgXhifry`: 40.106 DOT - `1QgMmM5QyTBVkC9cBNPVQszCTHjCBskFG1pny8zVprPSd1J`: 40.106 DOT - `1dwxEFdaRzBF1fpZqbXz71nLhJHvPi6a8eETjPSyC3Wrvom`: 40.106 DOT - `12wWLUd5qMzLFGqBsMnHLVFeTuYJwuo5ygMAxuSywrBX1XSF`: 40.106 DOT - `19C7X2ayEGaHbRb7obTd7u2crJhYm6W47XpyLC2jQBGdpif`: 40.106 DOT - `1316cTZeHz8HtEjaJRHu8sHbp9brtUmy2LiP74KZXgXhifry`: 40.106 DOT - `14DsLzVyTUTDMm2eP3czwPbH53KgqnQRp3CJJZS9GR7yxGDP`: 40.106 DOT - `1xgDfXcNuB94dDcKmEG8rE9x9JVoqozCBnnitkN9nAe3Nyx`: 40.106 DOT - `16kkgkzjyJZL91WaL6GAUJnTZjiaowZcFyHAs5GWCNVqJimJ`: 40.106 DOT - `16aQb7rHLB8UXzd2YSh56vjAELyyq8jYaj5QdAHjVjsA3ey9`: 40.106 DOT - `14jHouxT1VbhBDw93VW8Z89p139Qgu7ECHz3zxM2CpQEDJDB`: 40.106 DOT - `15fHj7Q7SYxqMgZ38UpjXS8cxdq77rczTP3JgY9JVi5piMPN`: 40.106 DOT - `149FXUmHgg75z4sk2LzFDyctNLHhzf2YxGMFHT7TakkbeQ7F`: 40.106 DOT - `12hAtDZJGt4of3m2GqZcUCVAjZPALfvPwvtUTFZPQUbdX1Ud`: 40.106 DOT - `13GtCixw3EZARj52CVbKLrsAzyc7dmmYhDV6quS5yeVCfnh1`: 40.106 DOT - `15ixta6FiXTBE8gXCTUNP3ahdYWcTuateHgB2czGg5EGDVMA`: 40.106 DOT - `15kgSF6oSMFeaN7xYAykihoyQFZLRu1cF5FaBdiSDHJ233H5`: 40.106 DOT - `13GtCixw3EZARj52CVbKLrsAzyc7dmmYhDV6quS5yeVCfnh1`: 40.106 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.106 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.106 DOT - `139Vbu9X3h4v7NTBVSpLijAvpWUoGhYwKmeuxaSJ9kQsD2SG`: 40.106 DOT - `128fHaGJDKeXNNjqamUTaLe5dpU41zpbBaQA6BW9VsPKpkH6`: 40.106 DOT - `15DL1EU6TpGDvL8HCNNU2ZDZdbcDUPiHYr1DBHBerUWMkJnT`: 40.106 DOT - `16agh1vhJ78MiJ7tjuTd9RzreMwBwTEu15x8kCDfJy1xBYUs`: 40.106 DOT - `16kkgkzjyJZL91WaL6GAUJnTZjiaowZcFyHAs5GWCNVqJimJ`: 40.106 DOT - `13SceNt2ELz3ti4rnQbY1snpYH4XE4fLFsW8ph9rpwJd6HFC`: 40.106 DOT - `1zhukWzj6pTskKUhDmyCaoJLuaHp5AVMDn5uLoNXTrw2gDR`: 40.106 DOT - `15fHj7Q7SYxqMgZ38UpjXS8cxdq77rczTP3JgY9JVi5piMPN`: 40.106 DOT - `12mRyiCp9zdh1wEVW5gLLiFBxDPKks72rRXmSupyEK3VAMLf`: 40.106 DOT - `13u5odFdy7uFmRLpbgtYGWeFy8rFkcD3bYfad49B81C31pwL`: 40.106 DOT - `16fUfF5mqL3cGGL3ai1CTL45UyNVTBHcbMkmuh5Va5M2yJ5p`: 40.106 DOT - `14mZVYo7jy13aHTiNMQZJzsii5CPsVEaMQwLXTEMLzkmxKH2`: 40.106 DOT - `1uamkTsQk6TwVAm6FvD7optu9fDPUh7GojEc2mZHym13Kcf`: 40.106 DOT - `14DsLzVyTUTDMm2eP3czwPbH53KgqnQRp3CJJZS9GR7yxGDP`: 40.106 DOT - `12CHAK3YxJG5pGW6JAGp6Daj8ruRfPwCNbPM7jU8mC2zh2qD`: 40.106 DOT - `123LuJKS65HaBbLSdDS46ByeC7bvQwA1iUhTpmjigQAfUKpK`: 40.106 DOT - `16k8FBUzGaAScYvewFB9g6WGt8Zms9oygPVKt7GioG4gimRp`: 40.106 DOT - `14QQcaXERr6kzwW55L4GKmN8tC8NJRoGt1jF5D8GMWoXdyaz`: 40.106 DOT - `13EAhGcpe93mqSFZQrQ4P2cfpdAo5txWc5UQVTfEKDoqZjhw`: 40.106 DOT - `15SN9iNKxCJJjQ5f6JXEDxiaS6bRHxxTZtsfm3wCSSjyoENg`: 40.106 DOT - `12mRyiCp9zdh1wEVW5gLLiFBxDPKks72rRXmSupyEK3VAMLf`: 40.106 DOT - `15SN9iNKxCJJjQ5f6JXEDxiaS6bRHxxTZtsfm3wCSSjyoENg`: 40.106 DOT - `15oXuEfGte2HPoxxWwz18er7LNFuLNEdXtNNk53dggkfFgCR`: 40.106 DOT - `16agh1vhJ78MiJ7tjuTd9RzreMwBwTEu15x8kCDfJy1xBYUs`: 40.106 DOT - `1EpEiYpWRAWmte4oPLtR5B1TZFxcBShBdjK4X9wWnq2KfLK`: 40.101 DOT - `13Ghf2T883ZobjngC1BAgR1BWvK2P7qP37gGxHDVFf3fjbmw`: 40.1 DOT - `13SceNt2ELz3ti4rnQbY1snpYH4XE4fLFsW8ph9rpwJd6HFC`: 40.099 DOT - `14DsLzVyTUTDMm2eP3czwPbH53KgqnQRp3CJJZS9GR7yxGDP`: 40.087 DOT - `1481qDmGELXNaeDi3jsLqHUSXLpSkaEg3euUX8Ya3SPoDLmt`: 40.075 DOT - `16Drp38QW5UXWMHT7n5d5mPPH1u5Qavuv6aYAhbHfN3nzToe`: 40.074 DOT - `14onpjYNgzDZwY57Y3w5cwwnFyp6K62mNNbgq4Xhw7zNG9iX`: 40.07 DOT - `15nKYvAm8Yu9QVK65JWrhfyabhHkWywg21X9gX4GFJo3v4cT`: 40.069 DOT - `138MRRCFovYvetAhv37SnNsZoCVyghYoUArhBzMzKFfFGeMP`: 40.067 DOT - `13u5odFdy7uFmRLpbgtYGWeFy8rFkcD3bYfad49B81C31pwL`: 40.067 DOT - `12NGmpotx1WxkZ6RrqZeMBerBUB2aa2fBCrhSPvbAJWAcF33`: 40.067 DOT - `1EpEiYpWRAWmte4oPLtR5B1TZFxcBShBdjK4X9wWnq2KfLK`: 40.067 DOT - `13YMTEPKAxPRiyaZdMKrozeNT9x1Pa5h7aExebCdi6nc3Qqd`: 40.067 DOT </p> </details> - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

To be merged into the AHM working branch. Changes: - Configure the RC Migrator pallet as call filter for the Polkadot Relay chain - Test - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Dónal Murray <donalm@seadanda.dev>

To be merged into the AHM working branch. # Pallet Nomination Pools The nomination pools pallet has 15 storage items of which 14 can be migrated without any translation. # Storage Values All nine storage values are migrated as is in a single message. # Storage Maps The `BondedPools` map needs translation for its commission logic. The Commission struct contains an absolute relay timestamp [throttle_from](https://github.com/paritytech/polkadot-sdk/blob/bf20a9ee18f7215210bbbabf79e955c8c35b3360/substrate/frame/nomination-pools/src/lib.rs#L737) and the commission change [min_delay](https://github.com/paritytech/polkadot-sdk/blob/bf20a9ee18f7215210bbbabf79e955c8c35b3360/substrate/frame/nomination-pools/src/lib.rs#L922). The translation for both happens upon arrival on the Asset Hub. Ideally, it would be done on the Relay chain side since we have more compute power there but it is not possible since the timestamp translation depends on the Relay number upon arrival on Asset Hub. The timestamp is translated in [rc_to_ah_timestamp](https://github.com/polkadot-fellows/runtimes/blob/5af776e1443b5e7eb17b6e9d87ef40311afaf6f9/pallets/ah-migrator/src/staking/nom_pools.rs#L127) and the `min_delay` is directly passed to `RcToAhDelay`. The other five storage maps are migrated as it. ## User Impact Impact here is negligible and only for pool operators - not members: - Pool commission change rate (measured in blocks) could be decreased by one block. - Pool operators may be able to change the commission rate one block later than anticipated. This is due to the nature or translating blocks of two different blockchains which does not yield unambiguous results. - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

meant to be merged into `dev-asset-hub-migration` branch referenda pallet migration --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

To be merged into the AHM working branch. Changes: - Clippy cleanup - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

meant to be merged into `dev-asset-hub-migration` The migration for the Scheduler pallet from Relay Chain to Asset Hub. --------- Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

To be merged into the AHM dev branch. There should be no user impact here - both pallets have their storage migrated exactly as is and the used times are always in Epoch. - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

WIP to be merged into the AHM dev branch. TODO write user impact. - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

meant to be merged into ahm dev branch The data migration for the conviction-voting pallet. --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

To be merged into the AHM working branch - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

meant to be merged into AHM dev branch Integrates asset rate pallet into Polkadot Asset Hub and introduces the data migration for the pallet. No user impact, no security concerns. --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

meant to be merged into ahm dev branch Migration bounties pallet data from RC to AH. --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

Merging into the AHM working branch. Depends on #579 # Pallet Vesting Pallet vesting has one storage map to hold the vesting schedules and one storage value to track the current version of the pallet. The version can be easily migrated, but for the schedules it is a bit difficult. ## Storage: Vesting The vesting schedules are already measured in relay blocks, as can be seen [here](https://github.com/polkadot-fellows/runtimes/blob/b613b54d94af5f4702533a56c6260651a14bdccb/system-parachains/asset-hubs/asset-hub-polkadot/src/lib.rs#L297). This means that we can just integrate the existing schedules. The only possibly issue is when there are lots of pre-existing schedules. The maximal number of schedules is 28; both on Relay and AH. We cannot use the merge functionality of the vesting pallet since that can be used as an attack vector: anyone can send 28 vested transfers with very large unlock duration and low amount to force all other schedules to adapt this long unlock period. This would reduce the rewards per block, which is bad. For now, we are writing all colliding AH schedules into a storage item for manual inspection later. It could still happen that unmalicious users will have more than 28 schedules, but as nobody has used the vested transfers on AH yet. Q: Maybe we should disable vested transfers with the next runtime upgrade on AH. ## Storage: StorageVersion The vesting pallet is not using the proper FRAME version tracking; rather, it tracks its version in the `StorageVersion` value. It does this incorrectly though, with Asset Hub reporting version 0 instead of 1. We ignore and correct this by writing 1 to the storage. ## User Impact This affects users that have vesting schedules on the Relay chain or on Asset Hub. There exists a risk that the number of total schedules exceeds 28, which means that they will not fit into the storage anymore. We then prioritize the schedules from AH and pause and stash all schedules that do not fit (up to 28). - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

The [configuration of the allowed_call_filters](https://github.com/polkadot-fellows/runtimes/blob/daf6723d4390db875c8e3d4a8bf8818f5e837351/relay/polkadot/src/lib.rs#L1582C1-L1583C70) doesn't match [their pallet documentation](https://github.com/polkadot-fellows/runtimes/blob/daf6723d4390db875c8e3d4a8bf8818f5e837351/pallets/rc-migrator/src/lib.rs#L338C3-L343C84) - judging by the names and documentation they should be reversed. Same for the [filter implementation](https://github.com/polkadot-fellows/runtimes/blob/daf6723d4390db875c8e3d4a8bf8818f5e837351/pallets/rc-migrator/src/lib.rs#L1116C4-L1122C4).

To be merged into the AHM working branch. Quote from `accounts.md`: # Account Migration Accounts are migrated with all their balance, locks and reserves at the beginning of the Asset Hub migration. ## User Impact Users need to be aware that all of their funds will be moved from the Relay chain to the Asset Hub. The Account ID will stay the same. This ensures that normal user accounts will be to control their funds on Asset Hub. ## Sovereign Account Translation For parachain sovereign accounts, it is not possible to just use the same account ID. The sovereign account address of a parachain is calculated differently, depending on whether it is the account on the Relay or a parachain (like Asset Hub). There are different kinds of sovereign accounts. In this context, we only focus on these parachain sovereign accounts: - On the Relay: derived from `"para" ++ para_id ++ 00..` - On the Asset Hub and all other sibling parachains: derived from `"sibl" ++ para_id ++ 00..` Our translation logic inverts the derivation and changes the prefix from `"para"` to `"sibl"` for all accounts that match the pattern `"para" ++ para_id ++ 00..`. The full list of translated accounts is in [this CSV file](./sovereign_account_translation.csv). It is advised that parachains check that they can control their account on Asset Hub. They can also forego this check if they do not need control thereof - for example when they are not holding any funds on their relay sovereign account. However, please note that someone could still send funds to that address before or after the migration. Example for Bifrost: this is the [relay sovereign account](https://polkadot.subscan.io/account/13YMK2eeopZtUNpeHnJ1Ws2HqMQG6Ts9PGCZYGyFbSYoZfcm) and it gets translated to this [sibling sovereign account](https://assethub-polkadot.subscan.io/account/13cKp89TtYknbyYnqnF6dWN75q5ZosvFSuqzoEVkUAaNR47A). --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

To be merged into the AHM branch TODO: write user impact and add tests - [x] Does not require a CHANGELOG entry --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: muharem <ismailov.m.h@gmail.com>

Set up a leaner migration testing framework for single pallets and implementing it for pallet `preimage`. This PR introduces the traits `RcMigrationChecks` and `AhMigrationChecks` for checks before and after a single pallet's migration. Upon implementing these traits for a pallet, you can use `rc_migrate` and `ah_migrate` functions to run a test on the correctness of the pallet's migration.

meant to be merged into ahm dev branch Stage management for the Asset Hub migration --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

Merges into the AHM branch - [x] Does not require a CHANGELOG entry Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

WIP --------- Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

Migrate accounts with free balance less than RC ED but with enough balance for AH ED. It turns out the Kusama has around 38k accounts with free balance less than RC ED but more/equal to AH ED. current accounts migration ignores these accounts. With the change presented in this PR we can migrate those accounts too.

…mark (#916) This PR reverts the workaround introduced in #910 and bumps EPMB pallet version to `0.3.2` to include SDK fix paritytech/polkadot-sdk#9778

muharem · 2025-09-23T15:00:40Z

relay/polkadot/src/weights/pallet_rc_migrator.rs

+		Weight::from_parts(10_000_000, 1000)
+	}
+	fn set_unprocessed_msg_buffer() -> Weight {
+		Weight::from_parts(10_000_000, 1000)


@ggwpez seems like we never generated weights for this pallet

@ggwpez seems like we never generated weights for this pallet

for Polkadot no, I am just running for Kusama here: #887,
do we need also polkadot now?

we discussed that we can have one more release for Polkadot. so this is not a blocker.

relay/kusama/constants/src/lib.rs

github-actions · 2025-09-23T15:28:30Z

Review required! Latest push from author must always be reviewed

franciscoaguirre · 2025-09-23T14:59:00Z