v1.18: blockstore: only consume duplicate proofs from root_slot + 1 o…

…n startup (backport of #1971) (#2113)

* blockstore: only consume duplicate proofs from root_slot + 1 on startup (#1971)

* blockstore: only consume duplicate proofs from root_slot + 1 on startup

* pr feedback: update test comments

* pr feedback: add pub behind dcou for test fns

(cherry picked from commit 2a48564)

* fix conflicts

---------

Co-authored-by: Ashwin Sekar <ashwin@anza.xyz>
Co-authored-by: Ashwin Sekar <ashwin@solana.com>

core/Cargo.toml

@@ -90,6 +90,7 @@ serde_json = { workspace = true }
 serial_test = { workspace = true }
 # See order-crates-for-publishing.py for using this unusual `path = "."`
 solana-core = { path = ".", features = ["dev-context-only-utils"] }
+solana-ledger = { workspace = true, features = ["dev-context-only-utils"] }
 solana-logger = { workspace = true }
 solana-poh = { workspace = true, features = ["dev-context-only-utils"] }
 solana-program-runtime = { workspace = true }

core/src/replay_stage.rs

@@ -1285,8 +1285,14 @@ impl ReplayStage {
     ) -> (ProgressMap, HeaviestSubtreeForkChoice) {
         let (root_bank, frozen_banks, duplicate_slot_hashes) = {
             let bank_forks = bank_forks.read().unwrap();
+            let root_bank = bank_forks.root_bank();
             let duplicate_slots = blockstore
-                .duplicate_slots_iterator(bank_forks.root_bank().slot())
+                // It is important that the root bank is not marked as duplicate on initialization.
+                // Although this bank could contain a duplicate proof, the fact that it was rooted
+                // either during a previous run or artificially means that we should ignore any
+                // duplicate proofs for the root slot, thus we start consuming duplicate proofs
+                // from the root slot + 1
+                .duplicate_slots_iterator(root_bank.slot().saturating_add(1))
                 .unwrap();
             let duplicate_slot_hashes = duplicate_slots.filter_map(|slot| {
                 let bank = bank_forks.get(slot)?;
@@ -1295,7 +1301,7 @@ impl ReplayStage {
                     .then_some((slot, bank.hash()))
             });
             (
-                bank_forks.root_bank(),
+                root_bank,
                 bank_forks.frozen_banks().values().cloned().collect(),
                 duplicate_slot_hashes.collect::<Vec<(Slot, Hash)>>(),
             )
@@ -4310,6 +4316,9 @@ pub(crate) mod tests {
             replay_stage::ReplayStage,
             vote_simulator::{self, VoteSimulator},
         },
+        blockstore_processor::{
+            confirm_full_slot, fill_blockstore_slot_with_ticks, process_bank_0, ProcessOptions,
+        },
         crossbeam_channel::unbounded,
         itertools::Itertools,
         solana_entry::entry::{self, Entry},
@@ -8963,4 +8972,125 @@ pub(crate) mod tests {
             &mut PurgeRepairSlotCounter::default(),
         );
     }
+
+    #[test]
+    fn test_initialize_progress_and_fork_choice_with_duplicates() {
+        solana_logger::setup();
+        let GenesisConfigInfo {
+            mut genesis_config, ..
+        } = create_genesis_config(123);
+
+        let ticks_per_slot = 1;
+        genesis_config.ticks_per_slot = ticks_per_slot;
+        let (ledger_path, blockhash) =
+            solana_ledger::create_new_tmp_ledger_auto_delete!(&genesis_config);
+        let blockstore = Blockstore::open(ledger_path.path()).unwrap();
+
+        /*
+          Bank forks with:
+               slot 0
+                 |
+               slot 1 -> Duplicate before restart, the restart slot
+                 |
+               slot 2
+                 |
+               slot 3 -> Duplicate before restart, artificially rooted
+                 |
+               slot 4 -> Duplicate before restart, artificially rooted
+                 |
+               slot 5 -> Duplicate before restart
+                 |
+               slot 6
+        */
+
+        let mut last_hash = blockhash;
+        for i in 0..6 {
+            last_hash =
+                fill_blockstore_slot_with_ticks(&blockstore, ticks_per_slot, i + 1, i, last_hash);
+        }
+        // Artifically root 3 and 4
+        blockstore.set_roots([3, 4].iter()).unwrap();
+
+        // Set up bank0
+        let bank_forks = BankForks::new_rw_arc(Bank::new_for_tests(&genesis_config));
+        let bank0 = bank_forks.read().unwrap().get_with_scheduler(0).unwrap();
+        let recyclers = VerifyRecyclers::default();
+
+        process_bank_0(
+            &bank0,
+            &blockstore,
+            &ProcessOptions::default(),
+            &recyclers,
+            None,
+            None,
+        );
+
+        // Mark block 1, 3, 4, 5 as duplicate
+        blockstore.store_duplicate_slot(1, vec![], vec![]).unwrap();
+        blockstore.store_duplicate_slot(3, vec![], vec![]).unwrap();
+        blockstore.store_duplicate_slot(4, vec![], vec![]).unwrap();
+        blockstore.store_duplicate_slot(5, vec![], vec![]).unwrap();
+
+        let bank1 = bank_forks.write().unwrap().insert(Bank::new_from_parent(
+            bank0.clone_without_scheduler(),
+            &Pubkey::default(),
+            1,
+        ));
+        confirm_full_slot(
+            &blockstore,
+            &bank1,
+            &ProcessOptions::default(),
+            &recyclers,
+            &mut ConfirmationProgress::new(bank0.last_blockhash()),
+            None,
+            None,
+            None,
+            &mut ExecuteTimings::default(),
+        )
+        .unwrap();
+
+        bank_forks.write().unwrap().set_root(
+            1,
+            &solana_runtime::accounts_background_service::AbsRequestSender::default(),
+            None,
+        );
+
+        let leader_schedule_cache = LeaderScheduleCache::new_from_bank(&bank1);
+
+        // process_blockstore_from_root() from slot 1 onwards
+        blockstore_processor::process_blockstore_from_root(
+            &blockstore,
+            &bank_forks,
+            &leader_schedule_cache,
+            &ProcessOptions::default(),
+            None,
+            None,
+            None,
+            &AbsRequestSender::default(),
+        )
+        .unwrap();
+
+        assert_eq!(bank_forks.read().unwrap().root(), 4);
+
+        // Verify that fork choice can be initialized and that the root is not marked duplicate
+        let (_progress, fork_choice) =
+            ReplayStage::initialize_progress_and_fork_choice_with_locked_bank_forks(
+                &bank_forks,
+                &Pubkey::new_unique(),
+                &Pubkey::new_unique(),
+                &blockstore,
+            );
+
+        let bank_forks = bank_forks.read().unwrap();
+        // 4 (the artificial root) is the tree root and no longer duplicate
+        assert_eq!(fork_choice.tree_root().0, 4);
+        assert!(fork_choice
+            .is_candidate(&(4, bank_forks.bank_hash(4).unwrap()))
+            .unwrap());
+
+        // 5 is still considered duplicate, so it is not a valid fork choice candidate
+        assert!(!fork_choice
+            .is_candidate(&(5, bank_forks.bank_hash(5).unwrap()))
+            .unwrap());
+    }
 }

ledger/Cargo.toml

@@ -29,6 +29,7 @@ mockall = { workspace = true }
 num_cpus = { workspace = true }
 num_enum = { workspace = true }
 prost = { workspace = true }
+qualifier_attr = { workspace = true }
 rand = { workspace = true }
 rand_chacha = { workspace = true }
 rayon = { workspace = true }

ledger/src/blockstore_processor.rs

@@ -1,3 +1,5 @@
+#[cfg(feature = "dev-context-only-utils")]
+use qualifier_attr::qualifiers;
 use {
     crate::{
         block_error::BlockError,
@@ -974,6 +976,7 @@ fn verify_ticks(
     Ok(())
 }
 
+#[cfg_attr(feature = "dev-context-only-utils", qualifiers(pub))]
 fn confirm_full_slot(
     blockstore: &Blockstore,
     bank: &BankWithScheduler,
@@ -1378,6 +1381,7 @@ fn confirm_slot_entries(
 }
 
 // Special handling required for processing the entries in slot 0
+#[cfg_attr(feature = "dev-context-only-utils", qualifiers(pub))]
 fn process_bank_0(
     bank0: &BankWithScheduler,
     blockstore: &Blockstore,