Shouldn't matter much, but this is run on every produced block so free
performance

**Summary:** This PR enables authoring of multiple blocks in one AURA
slot in the slot-based collator and stabilizes the slot-based collator.

## CLI Changes
The flag `--experimental-use-slot-based` is now marked as deprecated. I
opted to introduce `--authoring slot-based` instead of just removing the
`experimental` prefix. By introducing the `authoring` variant, we get
some future-proofing in case we want to introduce further options.

## Change Description
With elastic-scaling, we are able to author multiple blocks with a
single relay-chain parent. In the initial iteration, the interval
between two blocks was determined by the `slot_duration` of the
parachain. This PR introduces a more flexible model, where we try to
author multiple blocks in a single slot if the runtime allows it.

The block authoring loop is largely the same. The
[`SlotTimer`](https://github.com/paritytech/polkadot-sdk/blob/f1935bd9/cumulus/cli...

Closes #7573

@skunert  @bkchr



---------

Co-authored-by: Bastian Köcher <git@kchr.de>
Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Sebastian Kunert <skunert49@gmail.com>

- Closes https://github.com/paritytech/license-scanner/issues/44
- Silent because only comments are changed in the crates.

## What's inside

First, we change the file traversal mechanism from shell globbing to
walking through files which happens inside the `license-scanner` - so it
has knowledge about directory structure and can correlate files with
corresponding Cargo manifest.

Next, added `MIT-0` and `Unlicense` to the allowed list of licenses.
`Unlicense` appears only once across {Substrate,Cumulus,Polkadot} - in
`penpal-runtime`.

Finally, updated headers in files that do not match the corresponding
manifest license.

---------

Co-authored-by: cornholio <0@mcornholio.ru>

Part of https://github.com/paritytech/polkadot-sdk/issues/5079.

Removes all usage of the static async backing params, replacing them
with dynamically computed equivalent values (based on the claim queue
and scheduling lookahead).

Adds a new runtime API for querying the scheduling lookahead value. If
not present, falls back to 3 (the default value that is backwards
compatible with values we have on production networks for
allowed_ancestry_len)

Also resolves most of
https://github.com/paritytech/polkadot-sdk/issues/4447, removing code
that handles async backing not yet being enabled.
While doing this, I removed the support for collation protocol version 1
on collators, as it only worked for leaves not supporting async backing
(which are none).
I also unhooked the legacy v1 statement-distribution (for the same
reason as above). That subsystem is basically dead code now, so I had to
remove some of its tests as they would no longer pass (since the
subsystem no longer sends messages to the legacy variant). I did not
remove the entire legacy subsystem yet, as that would pollute this PR
too much. We can remove the entire v1 and v2 validation protocols in a
follow up PR.

In another PR: remove test files with names `prospective_parachains`
(it'd pollute this PR if we do now)

TODO:
- [x] add deprecation warnings
- [x] prdoc

---------

Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>

On top of https://github.com/paritytech/polkadot-sdk/pull/6757

Fixes https://github.com/paritytech/polkadot-sdk/issues/6858 by bumping
the `PARENT_SEARCH_DEPTH` constant to a larger value (30) and adds a
zombienet-sdk test that exercises the 12-core scenario.

This is a node-side limit that restricts the number of allowed pending
availability candidates when choosing the parent parablock during
authoring.
This limit is rather redundant, as the parachain runtime already
restricts the unincluded segment length to the configured value in the
[FixedVelocityConsensusHook](https://github.com/paritytech/polkadot-sdk/blob/88d900af

/cumulus/pallets/aura-ext/src/consensus_hook.rs#L35)
(which ideally should be equal to this `PARENT_SEARCH_DEPTH`).

For 12 cores, a value of 24 should be enough, but I bumped it to 30 to
have some extra buffer.

There are two other potential ways of fixing this:
- remove this constant altogether, as the parachain runtime already
makes those guarantees. Chose not to do this, as it can't hurt to have
an extra safeguard
- set this value to be equal to the uninlcuded segment size. This value
however is not exposed to the node-side and would require a new runtime
API, which seems overkill for a redundant check.

---------

Co-authored-by: Javier Viola <javier@parity.io>

Closes #7055

@skunert @bkchr



---------

Co-authored-by: Bastian Köcher <git@kchr.de>
Co-authored-by: command-bot <>
Co-authored-by: Sebastian Kunert <skunert49@gmail.com>

Follow-up to #6825, which introduced this bug.

We use the `can_build_upon` method to ask the runtime if it is fine to
build another block. The runtime checks this based on the
[`ConsensusHook`](https://github.com/paritytech/polkadot-sdk/blob/c1b7c302/cumulus/pallets/aura-ext/src/consensus_hook.rs#L110-L110)
implementation, the most popular one being the `FixedConsensusHook`.

In #6825 I removed a check that would always allow us to build when we
are building on an included block. Turns out this check is still
required when:
1. The [`UnincludedSegment`
](https://github.com/paritytech/polkadot-sdk/blob/c1b7c302

/cumulus/pallets/parachain-system/src/lib.rs#L758-L758)
storage item in pallet-parachain-system is equal or larger than the
unincluded segment.
2. We are calling the `can_build_upon` runtime API where the included
block has progressed offchain to the current parent block (so last entry
in the `UnincludedSegment` storage item).

In this scenario the last entry in `UnincludedSegment` does not have a
hash assigned yet (because it was not available in `on_finalize` of the
previous block). So the unincluded segment will be reported at its
maximum length which will forbid building another block.

Ideally we would have a more elegant solution than to rely on the
node-side here. But for now the check is reintroduced and a test is
added to not break it again by accident.

---------

Co-authored-by: command-bot <>
Co-authored-by: Michal Kucharczyk <1728078+michalkucharczyk@users.noreply.github.com>

closes #3967 

## Changes
We now use relay chain slots to measure velocity on chain. Previously we
were storing the current parachain slot. Then in `on_state_proof` of the
`ConsensusHook` we were checking how many blocks were athored in the
current parachain slot. This works well when the parachain slot time and
relay chain slot time is the same. With elastic scaling, we can have
parachain slot times lower than that of the relay chain. In these cases
we want to measure velocity in relation to the relay chain. This PR
adjusts that.


##  Migration
This PR includes a migration. Storage item `SlotInfo` of pallet
`aura-ext` is renamed to `RelaySlotInfo` to better reflect its new
content. A migration has been added that just kills the old storage
item. `RelaySlotInfo` will be `None` initially but its value will be
adjusted after one new relay chain slot arrives.

---------

Co-authored-by: command-bot <>
Co-authored-by: Bastian Köcher <git@kchr.de>

## Problem
In the parachain template we use the [fully verifying import queue

](https://github.com/paritytech/polkadot-sdk/blob/3d9eddbe/cumulus/client/consensus/aura/src/equivocation_import_queue.rs#L224-L224)
which does extra equivocation checks.

However, when we import a warp synced block with state, we don't set a
fork choice, leading to an incomplete block import pipeline and error
here:
https://github.com/paritytech/polkadot-sdk/blob/3d9eddbe/substrate/client/service/src/client/client.rs#L488-L488

This renders warp sync useless for chains using this import queue.

## Fix
The fix is to always import a block with state as best block, as we
already do in the normal Aura Verifier.
In a follow up we should also take another look into unifying the usage
of the different import queues.

fixes https://github.com/paritytech/project-mythical/issues/256

---------

Co-authored-by: command-bot <>

Move `RelayChainDataFetcher` to its own module and rename it to
`RelayChainDataCache`. Also move the `core_selector` function to the
`slot_based` module.

Related issue: https://github.com/paritytech/polkadot-sdk/issues/6495

The `SlotBasedBlockImport` job is to collect the storage proofs of all
blocks getting imported. These storage proofs alongside the block are
being forwarded to the collation task. Right now they are just being
thrown away. More logic will follow later. Basically this will be
required to include multiple blocks into one `PoV` which will then be
done by the collation task.

---------

Co-authored-by: Michal Kucharczyk <1728078+michalkucharczyk@users.noreply.github.com>
Co-authored-by: GitHub Action <action@github.com>

Move spawning of the slot-based collator into the `run` function. Also
the tasks are being spawned as blocking task and not just as normal
tasks.

---------

Co-authored-by: GitHub Action <action@github.com>

Resolves https://github.com/paritytech/polkadot-sdk/issues/6179

Runtime side of https://github.com/paritytech/polkadot-sdk/issues/5048

Send the core selector ump signal in cumulus. Guarded by a compile time
feature until nodes are upgraded to a version that includes
https://github.com/paritytech/polkadot-sdk/pull/5423 for gracefully
handling ump signals.

---------

Co-authored-by: GitHub Action <action@github.com>

Partially implements
https://github.com/paritytech/polkadot-sdk/issues/5048

- adds a core selection runtime API to cumulus and a generic way of
configuring it for a parachain
- modifies the slot based collator to utilise the claim queue and the
generic core selection

What's left to be implemented (in a follow-up PR):
- add the UMP signal for core selection into the parachain-system pallet

View the RFC for more context:
https://github.com/polkadot-fellows/RFCs/pull/103

---------

Co-authored-by: command-bot <>

This PR introduces a feature that allows to optionally enable using the
full PoV size.

Technically, we're ready to enable it by default, but as corresponding
runtime changes have not been propagated to the system parachain
runtimes yet, doing so could put them at risk. On the other hand, there
are teams that could benefit from it right now, and it makes no sense
for them to wait for the fellowship release and everything.

---------

Co-authored-by: Andrei Sandu <54316454+sandreim@users.noreply.github.com>

We only want to build one block per slot for Aura on parachains.
However, we still need to build on each relay chain fork, which is using
the same slot.

Closes: https://github.com/paritytech/polkadot-sdk/issues/5349

---------

Co-authored-by: Davide Galassi <davxy@datawok.net>
Co-authored-by: Sebastian Kunert <skunert49@gmail.com>

This pull requests adds a new CLI flag to `polkadot-parachains`
`--export-pov-to-path`. This CLI flag will instruct the node to export
any `PoV` that it build locally to export to the given folder. Then
these `PoV` files can be validated using the introduced
`cumulus-pov-validator`. The combination of export and validation can be
used for debugging parachain validation issues that may happen on the
relay chain.

Part of #3168 
On top of #3568

### Changes Overview
- Introduces a new collator variant in
`cumulus/client/consensus/aura/src/collators/slot_based/mod.rs`
- Two tasks are part of that module, one for block building and one for
collation building and submission.
- Introduces a new variant of `cumulus-test-runtime` which has 2s slot
duration, used for zombienet testing
- Zombienet tests for the new collator

**Note:** This collator is considered experimental and should only be
used for testing and exploration for now.

### Comparison with `lookahead` collator
- The new variant is slot based, meaning it waits for the next slot of
the parachain, then starts authoring
- The search for potential parents remains mostly unchanged from
lookahead
- As anchor, we use the current best relay parent
- In general, the new collator tends to be anchored to one relay parent
earlier. `lookahead` generally waits for a new relay block to arrive
before it attempts to build a block. ...

A few refactorings to block import and block verification that should
not be controversial.

Block verification before block import is stateless by design as
described in https://substrate.stackexchange.com/a/1322/25 and the fact
that it wasn't yet I consider to be a bug. Some code that requires it
had to use `Mutex`, but I do not expect it to have a measurable
performance impact.

Similarly with block import checking whether block preconditions should
not be an exclusive operation, there is nothing fundamentally wrong with
checking a few competing blocks whose parent blocks exist at the same
time (and even import them concurrently later, though IIRC this is not
yet implemented either).

They were originally a part of
https://github.com/paritytech/polkadot-sdk/pull/4842 and upstreaming
will help us to reduce the size of the patch we need to apply on top of
upstream code at Subspace every time we upgrade. There are no new
features introduced here, just refactoring to get rid of unnecessary
requirements.

This unifies the logic between `CallExecutor` and `Client` when it comes
to fetching the `code` for a given block. The actual `code` depends on
potential overrides/substitutes.

Besides that it changes the logic in the lookahead collator on which
`ValidationCodeHash` it sends to the validator alongside the `POV`. We
are now sending the code hash as found on the relay chain. This is done
as the local node could run with an override which is compatible to the
validation code on the relay chain, but has a different hash.

Inherited workspace dependencies cannot be renamed by the crate using
them (see [1](https://github.com/rust-lang/cargo/issues/12546),
[2](https://stackoverflow.com/questions/76792343/can-inherited-dependencies-in-rust-be-aliased-in-the-cargo-toml-file)).
Since we want to use inherited workspace dependencies everywhere, we
first need to unify all aliases that we use for a dependency throughout
the workspace.
The umbrella crate is currently excluded from this procedure, since it
should be able to export the crates by their original name without much
hassle.

For example: one crate may alias `parity-scale-codec` to `codec`, while
another crate does not alias it at all. After this change, all crates
have to use `codec` as name. The problematic combinations were:
- conflicting aliases: most crates aliases as `A` but some use `B`.
- missing alias: most of the crates alias a dep but some dont.
- superfluous alias: most crates dont alias a dep but some do.

The script that i used first determines whether most crates opted to
alias a dependency or not. From that info it decides whether to use an
alias or not. If it decided to use an alias, the most common one is used
everywhere.

To reproduce, i used
[this](https://github.com/ggwpez/substrate-scripts/blob/master/uniform-crate-alias.py)
python script in combination with
[this](https://github.com/ggwpez/zepter/blob/38ad10585fe98a5a86c1d2369738bc763a77057b/renames.json)
error output from Zepter.

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Bastian Köcher <git@kchr.de>

Some traits are already included in the 2021 prelude and so shouldn't be
needed to use explicitly:

use `convert::TryFrom`, `convert::TryInto`, and `iter::FromIterator` are
removed.

( https://doc.rust-lang.org/core/prelude/rust_2021/ )

No breaking changes or change of functionality, so I think no PR doc is
needed in this case.

(Motivation: Removes some references to `sp-std`)

This is phase 2 of async backing enablement for the system parachains on
the production networks. ~~It should be merged after
polkadot-fellows/runtimes#228 is enacted. After it is released,~~ all
the system parachain collators should be upgraded, and then we can
proceed with phase 3, which will enable async backing in the runtimes.

UPDATE: Indeed, we don't need to wait for the runtime upgrade enactions.
The lookahead collator handles the transition by itself, so we can
upgrade ASAP.

## Scope of changes

Here, we eliminate the dichotomy of having "generic Aura collators" for
the production system parachains and "lookahead Aura collators" for the
testnet system parachains. Now, all the collators are started as
lookahead ones, preserving the logic of transferring from the shell node
to Aura-enabled collators for the asset hubs. So, indeed, it simplifies
the parachain service logic, which cannot but rejoice.

Also while doing this, move slot duration fetching into the AURA code.

With Coretime enabled we can no longer assume there is a static 1:1
mapping between core index and para id. This mapping should be obtained
from the scheduler/claimqueue on block by block basis.

This PR modifies `para_id()` (from `CoreState`) to return the scheduled
`ParaId` for occupied cores and removes its usages in the code.

Closes https://github.com/paritytech/polkadot-sdk/issues/3948

---------

Co-authored-by: Andrei Sandu <54316454+sandreim@users.noreply.github.com>

This works only for collators that implement the `collator_fn` allowing
`collation-generation` subsystem to pull collations triggered on new
heads.

Also enables
`request_v2::CollationFetchingResponse::CollationWithParentHeadData` for
test adder/undying collators.

TODO:
- [x] fix tests
- [x] new tests
- [x] PR doc

---------

Signed-off-by: Andrei Sandu <andrei-mihail@parity.io>

Fixing: 
```
Verification failed for block 0x07bbf1e04121d70a4bdb21cc055132b53ac2390fa95c4d05497fc91b1e8bf7f5 received from (12D3KooWJzLd8skcAgA24EcJey7aJAhYctfUxWGjSP5Usk9wbpPZ): "Header 0x07bbf1e04121d70a4bdb21cc055132b53ac2390fa95c4d05497fc91b1e8bf7f5 rejected: too far in the future"   
```

---------

Signed-off-by: Alexandru Gheorghe <alexandru.gheorghe@parity.io>
Co-authored-by: Dmitry Sinyavin <dmitry.sinyavin@parity.io>
Co-authored-by: s0me0ne-unkn0wn <48632512+s0me0ne-unkn0wn@users.noreply.github.com>
Co-authored-by: Bastian Köcher <git@kchr.de>

This introduces a check to ensure that the parachain code matches the
validation code stored in the relay chain state. If not, it will print a
warning. This should be mainly useful for parachain builders to make
sure they have setup everything correctly.

Given how the block production is driven for Parachains right now, with
the enabling of async backing we would produce two blocks per slot.
Until we have a proper collator implementation, the "hack" is to prevent
the production of multiple blocks per slot.


Closes: https://github.com/paritytech/polkadot-sdk/issues/3282

It's a follow-up of #2949. It enables the lookahead collator to
dynamically adjust the aura slot size, which may change during the
runtime upgrade. It also addressed a couple of issues with time
constants I missed in the original PR.

Good news: it works. The parachain successfully switches from sync
backing with 12s slots to async backing with 6s slots.

Bad news: during the transitional period of a single block in which the
actual runtime upgrade is performed, it still gets the old slot duration
of 12s (as it gets it from the best block), resulting in a runtime panic
(logs follow). That doesn't affect the following block production of the
parachain. Ideas on how to improve the situation are appreciated.

<details>

```
2024-02-05 12:59:36.373  INFO tokio-runtime-worker sc_basic_authorship::basic_authorship: [Parachain] 🙌 Starting consensus session on top of parent 0x6fd2d8f904f12c22531bfabf77b16dc84a6a29e45d9ae358aa6547fbf3f0438b    
2024-02-05 12:59:36.373 ERROR tokio-runtime-worker runtime: [Parachain] panicked at /home/s0me0ne/wrk/parity/polkadot-sdk/cumulus/pallets/aura-ext/src/consensus_hook.rs:69:9:
assertion `left == right` failed: slot number mismatch
  left: Slot(142261198)
 right: Slot(284522396)    
2024-02-05 12:59:36.373  WARN tokio-runtime-worker sp_state_machine::overlayed_changes::changeset: [Parachain] 1 storage transactions are left open by the runtime. Those will be rolled back.    
2024-02-05 12:59:36.373  WARN tokio-runtime-worker sp_state_machine::overlayed_changes::changeset: [Parachain] 1 storage transactions are left open by the runtime. Those will be rolled back.    
2024-02-05 12:59:36.373  WARN tokio-runtime-worker basic-authorship: [Parachain] ❗ Inherent extrinsic returned unexpected error: Error at calling runtime api: Execution failed: Execution aborted due to trap: wasm trap: wasm `unreachable` instruction executed
WASM backtrace:
error while executing at wasm backtrace:
    0: 0x4e4a3b - <unknown>!rust_begin_unwind
    1: 0x46cf57 - <unknown>!core::panicking::panic_fmt::h3c280dba88683724
    2: 0x46d238 - <unknown>!core::panicking::assert_failed_inner::hebac5970933beb4d
    3: 0x3d00fc - <unknown>!core::panicking::assert_failed::h640a47e2fb5dfb4b
    4: 0xd0db3 - <unknown>!frame_support::storage::transactional::with_transaction::hcbc31515f81b2ee1
    5: 0x34d654 - <unknown>!<cumulus_pallet_parachain_system::pallet::Call<T> as frame_support::traits::dispatch::UnfilteredDispatchable>::dispatch_bypass_filter::{{closure}}::hb7c2c9a11fa88301
    6: 0x3547db - <unknown>!environmental::local_key::LocalKey<T>::with::h783f2605ae27d6d3
    7: 0x7f454 - <unknown>!<asset_hub_rococo_runtime::RuntimeCall as frame_support::traits::dispatch::UnfilteredDispatchable>::dispatch_bypass_filter::h5e11a01ab97c06c7
    8: 0x7f237 - <unknown>!<asset_hub_rococo_runtime::RuntimeCall as sp_runtime::traits::Dispatchable>::dispatch::h7f8ae4a8fede71ca
    9: 0x26a0f3 - <unknown>!frame_executive::Executive<System,Block,Context,UnsignedValidator,AllPalletsWithSystem,COnRuntimeUpgrade>::apply_extrinsic::h75e524ff34738391
   10: 0x282211 - <unknown>!BlockBuilder_apply_extrinsic. Dropping.    
2024-02-05 12:59:36.374 ERROR tokio-runtime-worker runtime: [Parachain] panicked at /home/s0me0ne/wrk/parity/polkadot-sdk/substrate/frame/aura/src/lib.rs:416:9:
assertion `left == right` failed: Timestamp slot must match `CurrentSlot`
  left: Slot(142261198)
 right: Slot(284522396)    
2024-02-05 12:59:36.374  WARN tokio-runtime-worker sp_state_machine::overlayed_changes::changeset: [Parachain] 1 storage transactions are left open by the runtime. Those will be rolled back.    
2024-02-05 12:59:36.374  WARN tokio-runtime-worker sp_state_machine::overlayed_changes::changeset: [Parachain] 1 storage transactions are left open by the runtime. Those will be rolled back.    
2024-02-05 12:59:36.374  WARN tokio-runtime-worker basic-authorship: [Parachain] ❗

 Inherent extrinsic returned unexpected error: Error at calling runtime api: Execution failed: Execution aborted due to trap: wasm trap: wasm `unreachable` instruction executed
WASM backtrace:
error while executing at wasm backtrace:
    0: 0x4e4a3b - <unknown>!rust_begin_unwind
    1: 0x46cf57 - <unknown>!core::panicking::panic_fmt::h3c280dba88683724
    2: 0x46d238 - <unknown>!core::panicking::assert_failed_inner::hebac5970933beb4d
    3: 0x3d00fc - <unknown>!core::panicking::assert_failed::h640a47e2fb5dfb4b
    4: 0x9ece6 - <unknown>!frame_support::storage::transactional::with_transaction::h26f75cb9f9462088
    5: 0x356d7e - <unknown>!environmental::local_key::LocalKey<T>::with::hbcf2d4e17b48fdb5
    6: 0x7f507 - <unknown>!<asset_hub_rococo_runtime::RuntimeCall as frame_support::traits::dispatch::UnfilteredDispatchable>::dispatch_bypass_filter::h5e11a01ab97c06c7
    7: 0x7f237 - <unknown>!<asset_hub_rococo_runtime::RuntimeCall as sp_runtime::traits::Dispatchable>::dispatch::h7f8ae4a8fede71ca
    8: 0x26a0f3 - <unknown>!frame_executive::Executive<System,Block,Context,UnsignedValidator,AllPalletsWithSystem,COnRuntimeUpgrade>::apply_extrinsic::h75e524ff34738391
    9: 0x282211 - <unknown>!BlockBuilder_apply_extrinsic. Dropping.    
2024-02-05 12:59:36.374 DEBUG tokio-runtime-worker runtime::xcmp-queue-migration: [Parachain] Lazy migration finished: item gone    
2024-02-05 12:59:36.374 ERROR tokio-runtime-worker runtime: [Parachain] panicked at /home/s0me0ne/wrk/parity/polkadot-sdk/cumulus/pallets/parachain-system/src/lib.rs:265:18:
set_validation_data inherent needs to be present in every block!    
2024-02-05 12:59:36.374 ERROR tokio-runtime-worker aura::cumulus: [Parachain] err=Error { inner: Proposing

Caused by:
    0: Error at calling runtime api: Execution failed: Execution aborted due to trap: wasm trap: wasm `unreachable` instruction executed
       WASM backtrace:
       error while executing at wasm backtrace:
           0: 0x4e4a3b - <unknown>!rust_begin_unwind
           1: 0x46cf57 - <unknown>!core::panicking::panic_fmt::h3c280dba88683724
           2: 0x46da8b - <unknown>!core::option::expect_failed::hdf18d99c3adabca7
           3: 0x2134cb - <unknown>!<cumulus_pallet_parachain_system::pallet::Pallet<T> as frame_support::traits::hooks::OnFinalize<<<<T as frame_system::pallet::Config>::Block as sp_runtime::traits::HeaderProvider>::HeaderT as sp_runtime::traits::Header>::Number>>::on_finalize::hf98aac39802896ba
           4: 0x26a9d6 - <unknown>!frame_executive::Executive<System,Block,Context,UnsignedValidator,AllPalletsWithSystem,COnRuntimeUpgrade>::idle_and_finalize_hook::h32775c0df0749d92
           5: 0x26ad9f - <unknown>!frame_executive::Executive<System,Block,Context,UnsignedValidator,AllPalletsWithSystem,COnRuntimeUpgrade>::finalize_block::h15e5a1a6b9ca8032
           6: 0x2822bd - <unknown>!BlockBuilder_finalize_block
    1: Execution failed: Execution aborted due to trap: wasm trap: wasm `unreachable` instruction executed
       WASM backtrace:
       error while executing at wasm backtrace:
           0: 0x4e4a3b - <unknown>!rust_begin_unwind
           1: 0x46cf57 - <unknown>!core::panicking::panic_fmt::h3c280dba88683724
           2: 0x46da8b - <unknown>!core::option::expect_failed::hdf18d99c3adabca7
           3: 0x2134cb - <unknown>!<cumulus_pallet_parachain_system::pallet::Pallet<T> as frame_support::traits::hooks::OnFinalize<<<<T as frame_system::pallet::Config>::Block as sp_runtime::traits::HeaderProvider>::HeaderT as sp_runtime::traits::Header>::Number>>::on_finalize::hf98aac39802896ba
           4: 0x26a9d6 - <unknown>!frame_executive::Executive<System,Block,Context,UnsignedValidator,AllPalletsWithSystem,COnRuntimeUpgrade>::idle_and_finalize_hook::h32775c0df0749d92
           5: 0x26ad9f - <unknown>!frame_executive::Executive<System,Block,Context,UnsignedValidator,AllPalletsWithSystem,COnRuntimeUpgrade>::finalize_block::h15e5a1a6b9ca8032
           6: 0x2822bd - <unknown>!BlockBuilder_finalize_block }
```

</details>

---------

Co-authored-by: Bastian Köcher <git@kchr.de>

The goal is to move all system chains on Rococo (+ other testnets?) to
use async backing.

Starting with `asset-hub-rococo` to get feedback, before I do the rest.

## Related

Example: https://github.com/paritytech/polkadot-sdk/pull/1619/
Guide:
https://github.com/w3f/polkadot-wiki/blob/master/docs/maintain/maintain-guides-async-backing.md

---------

Co-authored-by: Branislav Kontur <bkontur@gmail.com>
Co-authored-by: Dónal Murray <donal.murray@parity.io>

This splits `cumulus-primitives-parachain-inherent` into two crates, the
previous `cumulus-primitives-parachain-inherent` and a new
`cumulus-client-parachain-inherent`. The idea behind this is to move the
`create_at` logic into the client crate. This removes quite a lot of
unrelated dependencies from the runtime std build and thus, makes the
compilation faster. On my Laptop the compilation is goes down by one
minute for `asset-hub-rococo-runtime`. I also assume that the full build
of the entire workspace probably can be speed-up a little bit, because
more stuff can be compiled in parallel.

---------

Co-authored-by: command-bot <>

This opens up the proposer to only optionally create blocks. Nodes may
only make blocks when there are transactions or the chain is scheduled.

---------

Co-authored-by: command-bot <>

When launching our [small
network](https://github.com/paritytech/polkadot-sdk/blob/master/cumulus/zombienet/examples/small_network.toml)
for testing the node was crashing here shortly after launch:

https://github.com/paritytech/polkadot-sdk/blob/5cdd819e/polkadot/node/collation-generation/src/lib.rs#L140

After changes in #1788 for the asset hub collator we are waiting for
blocks of the shell runtime to pass before we initialize aura. However,
this means that we attempted to initialize the collation related relay
chain subsystems twice, leading to the error.

I modified Aura to let it optionally take an already initialized stream
of collation requests.

Partially addresses #1400

---------

Co-authored-by: Andrei Sandu <54316454+sandreim@users.noreply.github.com>

* Read allowed ancestry len from active config

* extract load_abridged_host_configuration

---------

Co-authored-by: Javier Viola <javier@parity.io>

* Add missing Cumulus licenses

* Typo

* Add missing Substrate licenses

* Single job checking the sub-repos in steps

* Remove dates

* Remove dates

* Add missing (C)

* Update FRAME UI tests

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

* Update more UI tests

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

---------

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

* deps: replace lru with schnellru

* bring the peace to the galaxy