diff --git a/br/pkg/lightning/backend/local/BUILD.bazel b/br/pkg/lightning/backend/local/BUILD.bazel
index 6e2b5e9a1c43c..c034e6bdb2b3c 100644
--- a/br/pkg/lightning/backend/local/BUILD.bazel
+++ b/br/pkg/lightning/backend/local/BUILD.bazel
@@ -94,7 +94,7 @@ go_test(
     ],
     embed = [":local"],
     flaky = True,
-    shard_count = 20,
+    shard_count = 40,
     deps = [
         "//br/pkg/errors",
         "//br/pkg/lightning/backend",
diff --git a/br/pkg/utils/BUILD.bazel b/br/pkg/utils/BUILD.bazel
index 0ae948d18a779..c3bcc629183d5 100644
--- a/br/pkg/utils/BUILD.bazel
+++ b/br/pkg/utils/BUILD.bazel
@@ -79,6 +79,7 @@ go_test(
     ],
     embed = [":utils"],
     flaky = True,
+    shard_count = 20,
     deps = [
         "//br/pkg/errors",
         "//br/pkg/metautil",
diff --git a/ddl/concurrentddltest/BUILD.bazel b/ddl/concurrentddltest/BUILD.bazel
index b70619f27da1a..d5acc141896c5 100644
--- a/ddl/concurrentddltest/BUILD.bazel
+++ b/ddl/concurrentddltest/BUILD.bazel
@@ -9,6 +9,7 @@ go_test(
     ],
     flaky = True,
     race = "on",
+    shard_count = 2,
     deps = [
         "//config",
         "//ddl",
diff --git a/ddl/metadatalocktest/mdl_test.go b/ddl/metadatalocktest/mdl_test.go
index 6f4a0012cdfff..64bdf77d55707 100644
--- a/ddl/metadatalocktest/mdl_test.go
+++ b/ddl/metadatalocktest/mdl_test.go
@@ -1105,3 +1105,16 @@ func TestMDLRenameTable(t *testing.T) {
 	tk.MustGetErrCode("select * from test2.t1;", mysql.ErrNoSuchTable)
 	tk.MustExec("commit")
 }
+
+func TestMDLPrepareFail(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+
+	tk := testkit.NewTestKit(t, store)
+	tk2 := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec("create table t(a int);")
+	_, _, _, err := tk.Session().PrepareStmt("select b from t")
+	require.Error(t, err)
+
+	tk2.MustExec("alter table test.t add column c int")
+}
diff --git a/executor/fktest/BUILD.bazel b/executor/fktest/BUILD.bazel
index dbdae1843edaf..86f7a48d28bb6 100644
--- a/executor/fktest/BUILD.bazel
+++ b/executor/fktest/BUILD.bazel
@@ -8,6 +8,7 @@ go_test(
         "main_test.go",
     ],
     flaky = True,
+    shard_count = 20,
     deps = [
         "//config",
         "//executor",
diff --git a/session/session.go b/session/session.go
index 824384367f33b..a6f5bf4cad0f1 100644
--- a/session/session.go
+++ b/session/session.go
@@ -2450,7 +2450,6 @@ func (s *session) PrepareStmt(sql string) (stmtID uint32, paramCount int, fields
 	}
 
 	ctx := context.Background()
-	inTxn := s.GetSessionVars().InTxn()
 	// NewPrepareExec may need startTS to build the executor, for example prepare statement has subquery in int.
 	// So we have to call PrepareTxnCtx here.
 	if err = s.PrepareTxnCtx(ctx); err != nil {
@@ -2467,13 +2466,12 @@ func (s *session) PrepareStmt(sql string) (stmtID uint32, paramCount int, fields
 	}
 	prepareExec := executor.NewPrepareExec(s, sql)
 	err = prepareExec.Next(ctx, nil)
+	// Rollback even if err is nil.
+	s.rollbackOnError(ctx)
+
 	if err != nil {
 		return
 	}
-	if !inTxn {
-		// We could start a transaction to build the prepare executor before, we should rollback it here.
-		s.RollbackTxn(ctx)
-	}
 	return prepareExec.ID, prepareExec.ParamCount, prepareExec.Fields, nil
 }