4 files changed, 32 insertions, 9 deletions

diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 08184fc40..fbb2a2223 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -807,16 +807,18 @@ difficulty_type Blockchain::get_difficulty_for_next_block()
 {
   LOG_PRINT_L3("Blockchain::" << __func__);
 
-  CRITICAL_REGION_LOCAL(m_difficulty_lock);
-  // we can call this without the blockchain lock, it might just give us
-  // something a bit out of date, but that's fine since anything which
-  // requires the blockchain lock will have acquired it in the first place,
-  // and it will be unlocked only when called from the getinfo RPC
   crypto::hash top_hash = get_tail_id();
-  if (top_hash == m_difficulty_for_next_block_top_hash)
-    return m_difficulty_for_next_block;
+  {
+    CRITICAL_REGION_LOCAL(m_difficulty_lock);
+    // we can call this without the blockchain lock, it might just give us
+    // something a bit out of date, but that's fine since anything which
+    // requires the blockchain lock will have acquired it in the first place,
+    // and it will be unlocked only when called from the getinfo RPC
+    if (top_hash == m_difficulty_for_next_block_top_hash)
+      return m_difficulty_for_next_block;
+  }
 
-  CRITICAL_REGION_LOCAL1(m_blockchain_lock);
+  CRITICAL_REGION_LOCAL(m_blockchain_lock);
   std::vector<uint64_t> timestamps;
   std::vector<difficulty_type> difficulties;
   auto height = m_db->height();
@@ -860,6 +862,8 @@ difficulty_type Blockchain::get_difficulty_for_next_block()
   }
   size_t target = get_difficulty_target();
   difficulty_type diff = next_difficulty(timestamps, difficulties, target);
+
+  CRITICAL_REGION_LOCAL1(m_difficulty_lock);
   m_difficulty_for_next_block_top_hash = top_hash;
   m_difficulty_for_next_block = diff;
   return diff;
@@ -3929,7 +3933,7 @@ uint64_t Blockchain::prevalidate_block_hashes(uint64_t height, const std::list<c
       // add to the known hashes array
       if (!valid)
       {
-        MWARNING("invalid hash for blocks " << n * HASH_OF_HASHES_STEP << " - " << (n * HASH_OF_HASHES_STEP + HASH_OF_HASHES_STEP - 1));
+        MDEBUG("invalid hash for blocks " << n * HASH_OF_HASHES_STEP << " - " << (n * HASH_OF_HASHES_STEP + HASH_OF_HASHES_STEP - 1));
         break;
       }
 
diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h
index 769e608ca..ef736d1e7 100644
--- a/src/cryptonote_core/blockchain.h
+++ b/src/cryptonote_core/blockchain.h
@@ -795,6 +795,13 @@ namespace cryptonote
     uint8_t get_hard_fork_version(uint64_t height) const { return m_hardfork->get(height); }
 
     /**
+     * @brief returns the earliest block a given version may activate
+     *
+     * @return the height
+     */
+    uint64_t get_earliest_ideal_height_for_version(uint8_t version) const { return m_hardfork->get_earliest_ideal_height_for_version(version); }
+
+    /**
      * @brief get information about hardfork voting for a version
      *
      * @param version the version in question
diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp
index d2796deeb..7d34415c4 100644
--- a/src/cryptonote_core/cryptonote_core.cpp
+++ b/src/cryptonote_core/cryptonote_core.cpp
@@ -1401,6 +1401,11 @@ namespace cryptonote
     return get_blockchain_storage().get_hard_fork_version(height);
   }
   //-----------------------------------------------------------------------------------------------
+  uint64_t core::get_earliest_ideal_height_for_version(uint8_t version) const
+  {
+    return get_blockchain_storage().get_earliest_ideal_height_for_version(version);
+  }
+  //-----------------------------------------------------------------------------------------------
   bool core::check_updates()
   {
     static const char software[] = "monero";
diff --git a/src/cryptonote_core/cryptonote_core.h b/src/cryptonote_core/cryptonote_core.h
index 17b5680e5..567966d48 100644
--- a/src/cryptonote_core/cryptonote_core.h
+++ b/src/cryptonote_core/cryptonote_core.h
@@ -663,6 +663,13 @@ namespace cryptonote
      uint8_t get_hard_fork_version(uint64_t height) const;
 
      /**
+      * @brief return the earliest block a given version may activate
+      *
+      * @return what it says above
+      */
+     uint64_t get_earliest_ideal_height_for_version(uint8_t version) const;
+
+     /**
       * @brief gets start_time
       *
       */