diff --git a/chain/store/store.go b/chain/store/store.go
index 620745c0939..e58669c14d6 100644
--- a/chain/store/store.go
+++ b/chain/store/store.go
@@ -809,12 +809,7 @@ func (cs *ChainStore) GetGenesis() (*types.BlockHeader, error) {
 		return nil, err
 	}
 
-	genb, err := cs.bs.Get(c)
-	if err != nil {
-		return nil, err
-	}
-
-	return types.DecodeBlock(genb.RawData())
+	return cs.GetBlock(c)
 }
 
 func (cs *ChainStore) GetCMessage(c cid.Cid) (types.ChainMsg, error) {
diff --git a/chain/vm/vm.go b/chain/vm/vm.go
index 6046f0d1aba..ae4c03f4a79 100644
--- a/chain/vm/vm.go
+++ b/chain/vm/vm.go
@@ -149,10 +149,10 @@ func (vm *VM) makeRuntime(ctx context.Context, msg *types.Message, parent *Runti
 		rt.Abortf(exitcode.SysErrForbidden, "message execution exceeds call depth")
 	}
 
-	rt.cst = &cbor.BasicIpldStore{
-		Blocks: &gasChargingBlocks{rt.chargeGasFunc(2), rt.pricelist, vm.cst.Blocks},
-		Atlas:  vm.cst.Atlas,
-	}
+	cbb := &gasChargingBlocks{rt.chargeGasFunc(2), rt.pricelist, vm.cst.Blocks}
+	cst := cbor.NewCborStore(cbb)
+	cst.Atlas = vm.cst.Atlas // associate the atlas.
+	vm.cst = cst
 
 	vmm := *msg
 	resF, ok := rt.ResolveAddress(msg.From)