1 files changed, 46 insertions, 0 deletions
diff --git a/nptl/tst-join7.c b/nptl/tst-join7.c
new file mode 100644
index 0000000..439d0fc
--- /dev/null
+++ b/nptl/tst-join7.c
@@ -0,0 +1,46 @@
+/* Verify that TLS access in separate thread in a dlopened library does not
+   deadlock.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <dlfcn.h>
+
+/* When one dynamically loads a module, which spawns a thread to perform some
+   activities, it could be possible that TLS storage is accessed for the first
+   time in that thread.  This results in an allocation request within the
+   thread, which could result in an attempt to take the rtld load_lock.  This
+   is a problem because it would then deadlock with the dlopen (which owns the
+   lock), if the main thread is waiting for the spawned thread to exit.  We can
+   at least ensure that this problem does not occur due to accesses within
+   libc.so, by marking TLS variables within libc.so as IE.  The problem of an
+   arbitrary variable being accessed and constructed within such a thread still
+   exists but this test case does not verify that.  */
+
+int
+do_test (void)
+{
+  void *f = dlopen ("tst-join7mod.so", RTLD_NOW | RTLD_GLOBAL);
+  if (f)
+    dlclose (f);
+  else
+    return 1;
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"