Merge bitcoin/bitcoin#30967: refactor: Replace g_genesis_wait_cv with m_tip_block_cv

fa22e5c430acaef9713d9a4b4b97bb3f4876f816 refactor: Remove dead code that assumed tip == nullptr (MarcoFalke)
fa2e4439652172df27f14508eef078bd0ee2fca5 refactor: Replace g_genesis_wait_cv with m_tip_block_cv (MarcoFalke)
fa7f52af1a47ebe3d1bc00e3bac70bf9f6fa769b refactor: Use wait_for predicate to check for interrupt (MarcoFalke)
5ca28ef28bcca1775ff49921fc2528d9439b71ab refactor: Split up NodeContext shutdown_signal and shutdown_request (Ryan Ofsky)
fad8e7fba7bf2c523a191309d392cab79668264b bugfix: Mark m_tip_block_cv as guarded by m_tip_block_mutex (MarcoFalke)
fa18586c29d4faba3d3f478eaabf9c4cbc1a16e2 refactor: Add missing GUARDED_BY(m_tip_block_mutex) (MarcoFalke)
fa4c0750331f36121ba92bbc2f22c615b7934e52 doc: Clarify waitTipChanged docs (MarcoFalke)

Pull request description:

  `g_genesis_wait_cv` is similar to `m_tip_block_cv` but shuffling everything through a redundant `boost::signals2`.

  So remove it, along with some other dead code, as well as minor fixups.

ACKs for top commit:
  ryanofsky:
    Code review ACK fa22e5c430acaef9713d9a4b4b97bb3f4876f816 (just rebased since last review)
  Sjors:
    ACK fa22e5c430acaef9713d9a4b4b97bb3f4876f816
  TheCharlatan:
    ACK fa22e5c430acaef9713d9a4b4b97bb3f4876f816

Tree-SHA512: a2cb59b651aaf85a3574723adfe403487566788ad945933b0458816ccc841fce08ca77b31afbd2d6adb5bf1deed7229c028bee74fb4bbaf6576e9edcfa0ad817

20 files changed, 87 insertions, 114 deletions

diff --git a/src/bitcoind.cpp b/src/bitcoind.cpp
index 1e27924dfd..9d08c42558 100644
--- a/src/bitcoind.cpp
+++ b/src/bitcoind.cpp
@@ -274,7 +274,7 @@ MAIN_FUNCTION
     if (ProcessInitCommands(args)) return EXIT_SUCCESS;
 
     // Start application
-    if (!AppInit(node) || !Assert(node.shutdown)->wait()) {
+    if (!AppInit(node) || !Assert(node.shutdown_signal)->wait()) {
         node.exit_status = EXIT_FAILURE;
     }
     Interrupt(node);
diff --git a/src/index/base.cpp b/src/index/base.cpp
index 810358394a..1a7eb9cd5e 100644
--- a/src/index/base.cpp
+++ b/src/index/base.cpp
@@ -31,7 +31,7 @@ template <typename... Args>
 void BaseIndex::FatalErrorf(util::ConstevalFormatString<sizeof...(Args)> fmt, const Args&... args)
 {
     auto message = tfm::format(fmt, args...);
-    node::AbortNode(m_chain->context()->shutdown, m_chain->context()->exit_status, Untranslated(message), m_chain->context()->warnings.get());
+    node::AbortNode(m_chain->context()->shutdown_request, m_chain->context()->exit_status, Untranslated(message), m_chain->context()->warnings.get());
 }
 
 CBlockLocator GetLocator(interfaces::Chain& chain, const uint256& block_hash)
diff --git a/src/init.cpp b/src/init.cpp
index 3b8474dd46..bf268d418c 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -207,7 +207,14 @@ void InitContext(NodeContext& node)
     g_shutdown.emplace();
 
     node.args = &gArgs;
-    node.shutdown = &*g_shutdown;
+    node.shutdown_signal = &*g_shutdown;
+    node.shutdown_request = [&node] {
+        assert(node.shutdown_signal);
+        if (!(*node.shutdown_signal)()) return false;
+        // Wake any threads that may be waiting for the tip to change.
+        if (node.notifications) WITH_LOCK(node.notifications->m_tip_block_mutex, node.notifications->m_tip_block_cv.notify_all());
+        return true;
+    };
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -235,7 +242,7 @@ void InitContext(NodeContext& node)
 
 bool ShutdownRequested(node::NodeContext& node)
 {
-    return bool{*Assert(node.shutdown)};
+    return bool{*Assert(node.shutdown_signal)};
 }
 
 #if HAVE_SYSTEM
@@ -286,7 +293,7 @@ void Shutdown(NodeContext& node)
 
     StopHTTPRPC();
     StopREST();
-    StopRPC(&node);
+    StopRPC();
     StopHTTPServer();
     for (const auto& client : node.chain_clients) {
         client->flush();
@@ -678,21 +685,6 @@ void SetupServerArgs(ArgsManager& argsman, bool can_listen_ipc)
     argsman.AddHiddenArgs(hidden_args);
 }
 
-static bool fHaveGenesis = false;
-static GlobalMutex g_genesis_wait_mutex;
-static std::condition_variable g_genesis_wait_cv;
-
-static void BlockNotifyGenesisWait(const CBlockIndex* pBlockIndex)
-{
-    if (pBlockIndex != nullptr) {
-        {
-            LOCK(g_genesis_wait_mutex);
-            fHaveGenesis = true;
-        }
-        g_genesis_wait_cv.notify_all();
-    }
-}
-
 #if HAVE_SYSTEM
 static void StartupNotify(const ArgsManager& args)
 {
@@ -707,7 +699,7 @@ static void StartupNotify(const ArgsManager& args)
 static bool AppInitServers(NodeContext& node)
 {
     const ArgsManager& args = *Assert(node.args);
-    if (!InitHTTPServer(*Assert(node.shutdown))) {
+    if (!InitHTTPServer(*Assert(node.shutdown_signal))) {
         return false;
     }
     StartRPC();
@@ -1216,7 +1208,7 @@ static ChainstateLoadResult InitAndLoadChainstate(
     };
     Assert(ApplyArgsManOptions(args, blockman_opts)); // no error can happen, already checked in AppInitParameterInteraction
     try {
-        node.chainman = std::make_unique<ChainstateManager>(*Assert(node.shutdown), chainman_opts, blockman_opts);
+        node.chainman = std::make_unique<ChainstateManager>(*Assert(node.shutdown_signal), chainman_opts, blockman_opts);
     } catch (std::exception& e) {
         return {ChainstateLoadStatus::FAILURE_FATAL, strprintf(Untranslated("Failed to initialize ChainstateManager: %s"), e.what())};
     }
@@ -1327,7 +1319,7 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
         constexpr uint64_t min_disk_space = 50 << 20; // 50 MB
         if (!CheckDiskSpace(args.GetBlocksDirPath(), min_disk_space)) {
             LogError("Shutting down due to lack of disk space!\n");
-            if (!(*Assert(node.shutdown))()) {
+            if (!(Assert(node.shutdown_request))()) {
                 LogError("Failed to send shutdown signal after disk space check\n");
             }
         }
@@ -1608,8 +1600,9 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
 
     // ********************************************************* Step 7: load block chain
 
-    node.notifications = std::make_unique<KernelNotifications>(*Assert(node.shutdown), node.exit_status, *Assert(node.warnings));
-    ReadNotificationArgs(args, *node.notifications);
+    node.notifications = std::make_unique<KernelNotifications>(Assert(node.shutdown_request), node.exit_status, *Assert(node.warnings));
+    auto& kernel_notifications{*node.notifications};
+    ReadNotificationArgs(args, kernel_notifications);
 
     // cache size calculations
     CacheSizes cache_sizes = CalculateCacheSizes(args, g_enabled_filter_types.size());
@@ -1649,7 +1642,7 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
             return false;
         }
         do_reindex = true;
-        if (!Assert(node.shutdown)->reset()) {
+        if (!Assert(node.shutdown_signal)->reset()) {
             LogError("Internal error: failed to reset shutdown signal.\n");
         }
         std::tie(status, error) = InitAndLoadChainstate(
@@ -1761,15 +1754,6 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
         }
     }
 
-    // Either install a handler to notify us when genesis activates, or set fHaveGenesis directly.
-    // No locking, as this happens before any background thread is started.
-    boost::signals2::connection block_notify_genesis_wait_connection;
-    if (WITH_LOCK(chainman.GetMutex(), return chainman.ActiveChain().Tip() == nullptr)) {
-        block_notify_genesis_wait_connection = uiInterface.NotifyBlockTip_connect(std::bind(BlockNotifyGenesisWait, std::placeholders::_2));
-    } else {
-        fHaveGenesis = true;
-    }
-
 #if HAVE_SYSTEM
     const std::string block_notify = args.GetArg("-blocknotify", "");
     if (!block_notify.empty()) {
@@ -1794,7 +1778,7 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
         ImportBlocks(chainman, vImportFiles);
         if (args.GetBoolArg("-stopafterblockimport", DEFAULT_STOPAFTERBLOCKIMPORT)) {
             LogPrintf("Stopping after block import\n");
-            if (!(*Assert(node.shutdown))()) {
+            if (!(Assert(node.shutdown_request))()) {
                 LogError("Failed to send shutdown signal after finishing block import\n");
             }
             return;
@@ -1814,15 +1798,11 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
     });
 
     // Wait for genesis block to be processed
-    {
-        WAIT_LOCK(g_genesis_wait_mutex, lock);
-        // We previously could hang here if shutdown was requested prior to
-        // ImportBlocks getting started, so instead we just wait on a timer to
-        // check ShutdownRequested() regularly.
-        while (!fHaveGenesis && !ShutdownRequested(node)) {
-            g_genesis_wait_cv.wait_for(lock, std::chrono::milliseconds(500));
-        }
-        block_notify_genesis_wait_connection.disconnect();
+    if (WITH_LOCK(chainman.GetMutex(), return chainman.ActiveTip() == nullptr)) {
+        WAIT_LOCK(kernel_notifications.m_tip_block_mutex, lock);
+        kernel_notifications.m_tip_block_cv.wait(lock, [&]() EXCLUSIVE_LOCKS_REQUIRED(kernel_notifications.m_tip_block_mutex) {
+            return !kernel_notifications.m_tip_block.IsNull() || ShutdownRequested(node);
+        });
     }
 
     if (ShutdownRequested(node)) {
@@ -1831,17 +1811,17 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
 
     // ********************************************************* Step 12: start node
 
-    //// debug print
     int64_t best_block_time{};
     {
-        LOCK(cs_main);
+        LOCK(chainman.GetMutex());
+        const auto& tip{*Assert(chainman.ActiveTip())};
         LogPrintf("block tree size = %u\n", chainman.BlockIndex().size());
-        chain_active_height = chainman.ActiveChain().Height();
-        best_block_time = chainman.ActiveChain().Tip() ? chainman.ActiveChain().Tip()->GetBlockTime() : chainman.GetParams().GenesisBlock().GetBlockTime();
+        chain_active_height = tip.nHeight;
+        best_block_time = tip.GetBlockTime();
         if (tip_info) {
             tip_info->block_height = chain_active_height;
             tip_info->block_time = best_block_time;
-            tip_info->verification_progress = GuessVerificationProgress(chainman.GetParams().TxData(), chainman.ActiveChain().Tip());
+            tip_info->verification_progress = GuessVerificationProgress(chainman.GetParams().TxData(), &tip);
         }
         if (tip_info && chainman.m_best_header) {
             tip_info->header_height = chainman.m_best_header->nHeight;
diff --git a/src/interfaces/mining.h b/src/interfaces/mining.h
index 421c5ba762..f71f7d7251 100644
--- a/src/interfaces/mining.h
+++ b/src/interfaces/mining.h
@@ -61,11 +61,11 @@ public:
     virtual std::optional<BlockRef> getTip() = 0;
 
     /**
-     * Waits for the tip to change
+     * Waits for the connected tip to change. If the tip was not connected on
+     * startup, this will wait.
      *
      * @param[in] current_tip block hash of the current chain tip. Function waits
-     *                        for the chain tip to change if this matches, otherwise
-     *                        it returns right away.
+     *                        for the chain tip to differ from this.
      * @param[in] timeout     how long to wait for a new tip
      * @returns               Hash and height of the current chain tip after this call.
      */
diff --git a/src/node/abort.cpp b/src/node/abort.cpp
index 8a17c41fd2..c15bf047c8 100644
--- a/src/node/abort.cpp
+++ b/src/node/abort.cpp
@@ -15,12 +15,12 @@
 
 namespace node {
 
-void AbortNode(util::SignalInterrupt* shutdown, std::atomic<int>& exit_status, const bilingual_str& message, node::Warnings* warnings)
+void AbortNode(const std::function<bool()>& shutdown_request, std::atomic<int>& exit_status, const bilingual_str& message, node::Warnings* warnings)
 {
     if (warnings) warnings->Set(Warning::FATAL_INTERNAL_ERROR, message);
     InitError(_("A fatal internal error occurred, see debug.log for details: ") + message);
     exit_status.store(EXIT_FAILURE);
-    if (shutdown && !(*shutdown)()) {
+    if (shutdown_request && !shutdown_request()) {
         LogError("Failed to send shutdown signal\n");
     };
 }
diff --git a/src/node/abort.h b/src/node/abort.h
index c881af4634..c8514628bc 100644
--- a/src/node/abort.h
+++ b/src/node/abort.h
@@ -6,16 +6,13 @@
 #define BITCOIN_NODE_ABORT_H
 
 #include <atomic>
+#include <functional>
 
 struct bilingual_str;
 
-namespace util {
-class SignalInterrupt;
-} // namespace util
-
 namespace node {
 class Warnings;
-void AbortNode(util::SignalInterrupt* shutdown, std::atomic<int>& exit_status, const bilingual_str& message, node::Warnings* warnings);
+void AbortNode(const std::function<bool()>& shutdown_request, std::atomic<int>& exit_status, const bilingual_str& message, node::Warnings* warnings);
 } // namespace node
 
 #endif // BITCOIN_NODE_ABORT_H
diff --git a/src/node/context.h b/src/node/context.h
index 398089ff3c..debc122120 100644
--- a/src/node/context.h
+++ b/src/node/context.h
@@ -59,8 +59,10 @@ struct NodeContext {
     std::unique_ptr<ECC_Context> ecc_context;
     //! Init interface for initializing current process and connecting to other processes.
     interfaces::Init* init{nullptr};
+    //! Function to request a shutdown.
+    std::function<bool()> shutdown_request;
     //! Interrupt object used to track whether node shutdown was requested.
-    util::SignalInterrupt* shutdown{nullptr};
+    util::SignalInterrupt* shutdown_signal{nullptr};
     std::unique_ptr<AddrMan> addrman;
     std::unique_ptr<CConnman> connman;
     std::unique_ptr<CTxMemPool> mempool;
diff --git a/src/node/interfaces.cpp b/src/node/interfaces.cpp
index febd968313..ec4777ba7f 100644
--- a/src/node/interfaces.cpp
+++ b/src/node/interfaces.cpp
@@ -134,13 +134,15 @@ public:
     }
     void startShutdown() override
     {
-        if (!(*Assert(Assert(m_context)->shutdown))()) {
+        NodeContext& ctx{*Assert(m_context)};
+        if (!(Assert(ctx.shutdown_request))()) {
             LogError("Failed to send shutdown signal\n");
         }
+
         // Stop RPC for clean shutdown if any of waitfor* commands is executed.
         if (args().GetBoolArg("-server", false)) {
             InterruptRPC();
-            StopRPC(m_context);
+            StopRPC();
         }
     }
     bool shutdownRequested() override { return ShutdownRequested(*Assert(m_context)); };
@@ -938,19 +940,12 @@ public:
 
     BlockRef waitTipChanged(uint256 current_tip, MillisecondsDouble timeout) override
     {
-        // Interrupt check interval
-        const MillisecondsDouble tick{1000};
-        auto now{std::chrono::steady_clock::now()};
-        auto deadline = now + timeout;
-        // std::chrono does not check against overflow
-        if (deadline < now) deadline = std::chrono::steady_clock::time_point::max();
+        if (timeout > std::chrono::years{100}) timeout = std::chrono::years{100}; // Upper bound to avoid UB in std::chrono
         {
             WAIT_LOCK(notifications().m_tip_block_mutex, lock);
-            while ((notifications().m_tip_block == uint256() || notifications().m_tip_block == current_tip) && !chainman().m_interrupt) {
-                now = std::chrono::steady_clock::now();
-                if (now >= deadline) break;
-                notifications().m_tip_block_cv.wait_until(lock, std::min(deadline, now + tick));
-            }
+            notifications().m_tip_block_cv.wait_for(lock, timeout, [&]() EXCLUSIVE_LOCKS_REQUIRED(notifications().m_tip_block_mutex) {
+                return (notifications().m_tip_block != current_tip && notifications().m_tip_block != uint256::ZERO) || chainman().m_interrupt;
+            });
         }
         // Must release m_tip_block_mutex before locking cs_main, to avoid deadlocks.
         LOCK(::cs_main);
diff --git a/src/node/kernel_notifications.cpp b/src/node/kernel_notifications.cpp
index 40d45c8c2b..05fe2f2248 100644
--- a/src/node/kernel_notifications.cpp
+++ b/src/node/kernel_notifications.cpp
@@ -58,7 +58,7 @@ kernel::InterruptResult KernelNotifications::blockTip(SynchronizationState state
 
     uiInterface.NotifyBlockTip(state, &index);
     if (m_stop_at_height && index.nHeight >= m_stop_at_height) {
-        if (!m_shutdown()) {
+        if (!m_shutdown_request()) {
             LogError("Failed to send shutdown signal after reaching stop height\n");
         }
         return kernel::Interrupted{};
@@ -90,12 +90,12 @@ void KernelNotifications::warningUnset(kernel::Warning id)
 
 void KernelNotifications::flushError(const bilingual_str& message)
 {
-    AbortNode(&m_shutdown, m_exit_status, message, &m_warnings);
+    AbortNode(m_shutdown_request, m_exit_status, message, &m_warnings);
 }
 
 void KernelNotifications::fatalError(const bilingual_str& message)
 {
-    node::AbortNode(m_shutdown_on_fatal_error ? &m_shutdown : nullptr,
+    node::AbortNode(m_shutdown_on_fatal_error ? m_shutdown_request : nullptr,
                     m_exit_status, message, &m_warnings);
 }
 
diff --git a/src/node/kernel_notifications.h b/src/node/kernel_notifications.h
index 9ff980ea56..296b9c426d 100644
--- a/src/node/kernel_notifications.h
+++ b/src/node/kernel_notifications.h
@@ -13,6 +13,7 @@
 
 #include <atomic>
 #include <cstdint>
+#include <functional>
 
 class ArgsManager;
 class CBlockIndex;
@@ -23,10 +24,6 @@ namespace kernel {
 enum class Warning;
 } // namespace kernel
 
-namespace util {
-class SignalInterrupt;
-} // namespace util
-
 namespace node {
 
 class Warnings;
@@ -35,8 +32,8 @@ static constexpr int DEFAULT_STOPATHEIGHT{0};
 class KernelNotifications : public kernel::Notifications
 {
 public:
-    KernelNotifications(util::SignalInterrupt& shutdown, std::atomic<int>& exit_status, node::Warnings& warnings)
-        : m_shutdown(shutdown), m_exit_status{exit_status}, m_warnings{warnings} {}
+    KernelNotifications(const std::function<bool()>& shutdown_request, std::atomic<int>& exit_status, node::Warnings& warnings)
+        : m_shutdown_request(shutdown_request), m_exit_status{exit_status}, m_warnings{warnings} {}
 
     [[nodiscard]] kernel::InterruptResult blockTip(SynchronizationState state, CBlockIndex& index) override EXCLUSIVE_LOCKS_REQUIRED(!m_tip_block_mutex);
 
@@ -58,12 +55,14 @@ public:
     bool m_shutdown_on_fatal_error{true};
 
     Mutex m_tip_block_mutex;
-    std::condition_variable m_tip_block_cv;
+    std::condition_variable m_tip_block_cv GUARDED_BY(m_tip_block_mutex);
     //! The block for which the last blockTip notification was received for.
-    uint256 m_tip_block;
+    //! The initial ZERO means that no block has been connected yet, which may
+    //! be true even long after startup, until shutdown.
+    uint256 m_tip_block GUARDED_BY(m_tip_block_mutex){uint256::ZERO};
 
 private:
-    util::SignalInterrupt& m_shutdown;
+    const std::function<bool()>& m_shutdown_request;
     std::atomic<int>& m_exit_status;
     node::Warnings& m_warnings;
 };
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 086f609ac3..6c844ffc8f 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -169,7 +169,7 @@ static RPCHelpMan stop()
 {
     // Event loop will exit after current HTTP requests have been handled, so
     // this reply will get back to the client.
-    CHECK_NONFATAL((*CHECK_NONFATAL(EnsureAnyNodeContext(jsonRequest.context).shutdown))());
+    CHECK_NONFATAL((CHECK_NONFATAL(EnsureAnyNodeContext(jsonRequest.context).shutdown_request))());
     if (jsonRequest.params[0].isNum()) {
         UninterruptibleSleep(std::chrono::milliseconds{jsonRequest.params[0].getInt<int>()});
     }
@@ -294,7 +294,7 @@ void InterruptRPC()
     });
 }
 
-void StopRPC(const std::any& context)
+void StopRPC()
 {
     static std::once_flag g_rpc_stop_flag;
     // This function could be called twice if the GUI has been started with -server=1.
@@ -303,9 +303,6 @@ void StopRPC(const std::any& context)
         LogDebug(BCLog::RPC, "Stopping RPC\n");
         WITH_LOCK(g_deadline_timers_mutex, deadlineTimers.clear());
         DeleteAuthCookie();
-        node::NodeContext& node = EnsureAnyNodeContext(context);
-        // The notifications interface doesn't exist between initialization step 4a and 7.
-        if (node.notifications) node.notifications->m_tip_block_cv.notify_all();
         LogDebug(BCLog::RPC, "RPC stopped.\n");
     });
 }
diff --git a/src/rpc/server.h b/src/rpc/server.h
index a8896d4247..5a22279a58 100644
--- a/src/rpc/server.h
+++ b/src/rpc/server.h
@@ -9,7 +9,6 @@
 #include <rpc/request.h>
 #include <rpc/util.h>
 
-#include <any>
 #include <functional>
 #include <map>
 #include <stdint.h>
@@ -173,7 +172,7 @@ extern CRPCTable tableRPC;
 
 void StartRPC();
 void InterruptRPC();
-void StopRPC(const std::any& context);
+void StopRPC();
 UniValue JSONRPCExec(const JSONRPCRequest& jreq, bool catch_errors);
 
 #endif // BITCOIN_RPC_SERVER_H
diff --git a/src/test/blockfilter_index_tests.cpp b/src/test/blockfilter_index_tests.cpp
index f6024f1ef3..48ae874fcd 100644
--- a/src/test/blockfilter_index_tests.cpp
+++ b/src/test/blockfilter_index_tests.cpp
@@ -144,7 +144,7 @@ BOOST_FIXTURE_TEST_CASE(blockfilter_index_initial_sync, BuildChainTestingSetup)
     BOOST_REQUIRE(filter_index.StartBackgroundSync());
 
     // Allow filter index to catch up with the block index.
-    IndexWaitSynced(filter_index, *Assert(m_node.shutdown));
+    IndexWaitSynced(filter_index, *Assert(m_node.shutdown_signal));
 
     // Check that filter index has all blocks that were in the chain before it started.
     {
diff --git a/src/test/blockmanager_tests.cpp b/src/test/blockmanager_tests.cpp
index 121f00bd25..c2b95dd861 100644
--- a/src/test/blockmanager_tests.cpp
+++ b/src/test/blockmanager_tests.cpp
@@ -28,13 +28,13 @@ BOOST_FIXTURE_TEST_SUITE(blockmanager_tests, BasicTestingSetup)
 BOOST_AUTO_TEST_CASE(blockmanager_find_block_pos)
 {
     const auto params {CreateChainParams(ArgsManager{}, ChainType::MAIN)};
-    KernelNotifications notifications{*Assert(m_node.shutdown), m_node.exit_status, *Assert(m_node.warnings)};
+    KernelNotifications notifications{Assert(m_node.shutdown_request), m_node.exit_status, *Assert(m_node.warnings)};
     const BlockManager::Options blockman_opts{
         .chainparams = *params,
         .blocks_dir = m_args.GetBlocksDirPath(),
         .notifications = notifications,
     };
-    BlockManager blockman{*Assert(m_node.shutdown), blockman_opts};
+    BlockManager blockman{*Assert(m_node.shutdown_signal), blockman_opts};
     // simulate adding a genesis block normally
     BOOST_CHECK_EQUAL(blockman.SaveBlockToDisk(params->GenesisBlock(), 0).nPos, BLOCK_SERIALIZATION_HEADER_SIZE);
     // simulate what happens during reindex
@@ -135,13 +135,13 @@ BOOST_FIXTURE_TEST_CASE(blockmanager_block_data_availability, TestChain100Setup)
 
 BOOST_AUTO_TEST_CASE(blockmanager_flush_block_file)
 {
-    KernelNotifications notifications{*Assert(m_node.shutdown), m_node.exit_status, *Assert(m_node.warnings)};
+    KernelNotifications notifications{Assert(m_node.shutdown_request), m_node.exit_status, *Assert(m_node.warnings)};
     node::BlockManager::Options blockman_opts{
         .chainparams = Params(),
         .blocks_dir = m_args.GetBlocksDirPath(),
         .notifications = notifications,
     };
-    BlockManager blockman{*Assert(m_node.shutdown), blockman_opts};
+    BlockManager blockman{*Assert(m_node.shutdown_signal), blockman_opts};
 
     // Test blocks with no transactions, not even a coinbase
     CBlock block1;
diff --git a/src/test/coinstatsindex_tests.cpp b/src/test/coinstatsindex_tests.cpp
index 08814c1499..e09aad05e9 100644
--- a/src/test/coinstatsindex_tests.cpp
+++ b/src/test/coinstatsindex_tests.cpp
@@ -35,7 +35,7 @@ BOOST_FIXTURE_TEST_CASE(coinstatsindex_initial_sync, TestChain100Setup)
 
     BOOST_REQUIRE(coin_stats_index.StartBackgroundSync());
 
-    IndexWaitSynced(coin_stats_index, *Assert(m_node.shutdown));
+    IndexWaitSynced(coin_stats_index, *Assert(m_node.shutdown_signal));
 
     // Check that CoinStatsIndex works for genesis block.
     const CBlockIndex* genesis_block_index;
@@ -86,7 +86,7 @@ BOOST_FIXTURE_TEST_CASE(coinstatsindex_unclean_shutdown, TestChain100Setup)
         CoinStatsIndex index{interfaces::MakeChain(m_node), 1 << 20};
         BOOST_REQUIRE(index.Init());
         BOOST_REQUIRE(index.StartBackgroundSync());
-        IndexWaitSynced(index, *Assert(m_node.shutdown));
+        IndexWaitSynced(index, *Assert(m_node.shutdown_signal));
         std::shared_ptr<const CBlock> new_block;
         CBlockIndex* new_block_index = nullptr;
         {
diff --git a/src/test/txindex_tests.cpp b/src/test/txindex_tests.cpp
index 5a32b02ad9..9ee5387830 100644
--- a/src/test/txindex_tests.cpp
+++ b/src/test/txindex_tests.cpp
@@ -33,7 +33,7 @@ BOOST_FIXTURE_TEST_CASE(txindex_initial_sync, TestChain100Setup)
     BOOST_REQUIRE(txindex.StartBackgroundSync());
 
     // Allow tx index to catch up with the block index.
-    IndexWaitSynced(txindex, *Assert(m_node.shutdown));
+    IndexWaitSynced(txindex, *Assert(m_node.shutdown_signal));
 
     // Check that txindex excludes genesis block transactions.
     const CBlock& genesis_block = Params().GenesisBlock();
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index fa89ceb332..7465846356 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -104,7 +104,8 @@ static void ExitFailure(std::string_view str_err)
 BasicTestingSetup::BasicTestingSetup(const ChainType chainType, TestOpts opts)
     : m_args{}
 {
-    m_node.shutdown = &m_interrupt;
+    m_node.shutdown_signal = &m_interrupt;
+    m_node.shutdown_request = [this]{ return m_interrupt(); };
     m_node.args = &gArgs;
     std::vector<const char*> arguments = Cat(
         {
@@ -224,7 +225,7 @@ ChainTestingSetup::ChainTestingSetup(const ChainType chainType, TestOpts opts)
 
     m_cache_sizes = CalculateCacheSizes(m_args);
 
-    m_node.notifications = std::make_unique<KernelNotifications>(*Assert(m_node.shutdown), m_node.exit_status, *Assert(m_node.warnings));
+    m_node.notifications = std::make_unique<KernelNotifications>(Assert(m_node.shutdown_request), m_node.exit_status, *Assert(m_node.warnings));
 
     m_make_chainman = [this, &chainparams, opts] {
         Assert(!m_node.chainman);
@@ -245,7 +246,7 @@ ChainTestingSetup::ChainTestingSetup(const ChainType chainType, TestOpts opts)
             .blocks_dir = m_args.GetBlocksDirPath(),
             .notifications = chainman_opts.notifications,
         };
-        m_node.chainman = std::make_unique<ChainstateManager>(*Assert(m_node.shutdown), chainman_opts, blockman_opts);
+        m_node.chainman = std::make_unique<ChainstateManager>(*Assert(m_node.shutdown_signal), chainman_opts, blockman_opts);
         LOCK(m_node.chainman->GetMutex());
         m_node.chainman->m_blockman.m_block_tree_db = std::make_unique<BlockTreeDB>(DBParams{
             .path = m_args.GetDataDirNet() / "blocks" / "index",
diff --git a/src/test/validation_chainstate_tests.cpp b/src/test/validation_chainstate_tests.cpp
index 702af6578d..c9cca8af04 100644
--- a/src/test/validation_chainstate_tests.cpp
+++ b/src/test/validation_chainstate_tests.cpp
@@ -70,14 +70,18 @@ BOOST_AUTO_TEST_CASE(validation_chainstate_resize_caches)
 BOOST_FIXTURE_TEST_CASE(chainstate_update_tip, TestChain100Setup)
 {
     ChainstateManager& chainman = *Assert(m_node.chainman);
-    uint256 curr_tip = m_node.notifications->m_tip_block;
+    const auto get_notify_tip{[&]() {
+        LOCK(m_node.notifications->m_tip_block_mutex);
+        return m_node.notifications->m_tip_block;
+    }};
+    uint256 curr_tip = get_notify_tip();
 
     // Mine 10 more blocks, putting at us height 110 where a valid assumeutxo value can
     // be found.
     mineBlocks(10);
 
     // After adding some blocks to the tip, best block should have changed.
-    BOOST_CHECK(m_node.notifications->m_tip_block != curr_tip);
+    BOOST_CHECK(get_notify_tip() != curr_tip);
 
     // Grab block 1 from disk; we'll add it to the background chain later.
     std::shared_ptr<CBlock> pblockone = std::make_shared<CBlock>();
@@ -92,15 +96,15 @@ BOOST_FIXTURE_TEST_CASE(chainstate_update_tip, TestChain100Setup)
     // Ensure our active chain is the snapshot chainstate.
     BOOST_CHECK(WITH_LOCK(::cs_main, return chainman.IsSnapshotActive()));
 
-    curr_tip = m_node.notifications->m_tip_block;
+    curr_tip = get_notify_tip();
 
     // Mine a new block on top of the activated snapshot chainstate.
     mineBlocks(1);  // Defined in TestChain100Setup.
 
     // After adding some blocks to the snapshot tip, best block should have changed.
-    BOOST_CHECK(m_node.notifications->m_tip_block != curr_tip);
+    BOOST_CHECK(get_notify_tip() != curr_tip);
 
-    curr_tip = m_node.notifications->m_tip_block;
+    curr_tip = get_notify_tip();
 
     BOOST_CHECK_EQUAL(chainman.GetAll().size(), 2);
 
@@ -136,10 +140,10 @@ BOOST_FIXTURE_TEST_CASE(chainstate_update_tip, TestChain100Setup)
     // Ensure tip is as expected
     BOOST_CHECK_EQUAL(background_cs.m_chain.Tip()->GetBlockHash(), pblockone->GetHash());
 
-    // g_best_block should be unchanged after adding a block to the background
+    // get_notify_tip() should be unchanged after adding a block to the background
     // validation chain.
     BOOST_CHECK(block_added);
-    BOOST_CHECK_EQUAL(curr_tip, m_node.notifications->m_tip_block);
+    BOOST_CHECK_EQUAL(curr_tip, get_notify_tip());
 }
 
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/validation_chainstatemanager_tests.cpp b/src/test/validation_chainstatemanager_tests.cpp
index b4fcfbd853..6c2a825e64 100644
--- a/src/test/validation_chainstatemanager_tests.cpp
+++ b/src/test/validation_chainstatemanager_tests.cpp
@@ -382,7 +382,7 @@ struct SnapshotTestSetup : TestChain100Setup {
             LOCK(::cs_main);
             chainman.ResetChainstates();
             BOOST_CHECK_EQUAL(chainman.GetAll().size(), 0);
-            m_node.notifications = std::make_unique<KernelNotifications>(*Assert(m_node.shutdown), m_node.exit_status, *Assert(m_node.warnings));
+            m_node.notifications = std::make_unique<KernelNotifications>(Assert(m_node.shutdown_request), m_node.exit_status, *Assert(m_node.warnings));
             const ChainstateManager::Options chainman_opts{
                 .chainparams = ::Params(),
                 .datadir = chainman.m_options.datadir,
@@ -397,7 +397,7 @@ struct SnapshotTestSetup : TestChain100Setup {
             // For robustness, ensure the old manager is destroyed before creating a
             // new one.
             m_node.chainman.reset();
-            m_node.chainman = std::make_unique<ChainstateManager>(*Assert(m_node.shutdown), chainman_opts, blockman_opts);
+            m_node.chainman = std::make_unique<ChainstateManager>(*Assert(m_node.shutdown_signal), chainman_opts, blockman_opts);
         }
         return *Assert(m_node.chainman);
     }
diff --git a/src/validation.cpp b/src/validation.cpp
index 5da3387ad2..d4ec42015b 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -3533,7 +3533,6 @@ bool Chainstate::ActivateBestChain(BlockValidationState& state, std::shared_ptr<
                     m_chainman.m_options.signals->UpdatedBlockTip(pindexNewTip, pindexFork, still_in_ibd);
                 }
 
-                // Always notify the UI if a new block tip was connected
                 if (kernel::IsInterrupted(m_chainman.GetNotifications().blockTip(GetSynchronizationState(still_in_ibd, m_chainman.m_blockman.m_blockfiles_indexed), *pindexNewTip))) {
                     // Just breaking and returning success for now. This could
                     // be changed to bubble up the kernel::Interrupted value to