diff --git a/src/index/base.cpp b/src/index/base.cpp
index f1e947cef0..be5676b1fc 100644
--- a/src/index/base.cpp
+++ b/src/index/base.cpp
@@ -68,7 +68,7 @@ bool BaseIndex::Init()
     return true;
 }
 
-static const CBlockIndex* NextSyncBlock(const CBlockIndex* pindex_prev)
+static const CBlockIndex* NextSyncBlock(const CBlockIndex* pindex_prev) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 {
     AssertLockHeld(cs_main);
 
diff --git a/src/validation.h b/src/validation.h
index fbdab04016..d5fd585a22 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -274,7 +274,7 @@ bool LoadGenesisBlock(const CChainParams& chainparams);
  * initializing state if we're running with -reindex. */
 bool LoadBlockIndex(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 /** Update the chain tip based on database information. */
-bool LoadChainTip(const CChainParams& chainparams);
+bool LoadChainTip(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 /** Unload database information */
 void UnloadBlockIndex();
 /** Run instances of script checking worker threads */
@@ -450,7 +450,7 @@ inline CBlockIndex* LookupBlockIndex(const uint256& hash)
 }
 
 /** Find the last common block between the parameter chain and a locator. */
-CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator);
+CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /** Mark a block as precious and reorganize.
  *