| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame^] | 1 | /* Verify that TLS access in separate thread in a dlopened library does not |
| 2 | deadlock. |
| 3 | Copyright (C) 2015-2016 Free Software Foundation, Inc. |
| 4 | This file is part of the GNU C Library. |
| 5 | |
| 6 | The GNU C Library is free software; you can redistribute it and/or |
| 7 | modify it under the terms of the GNU Lesser General Public |
| 8 | License as published by the Free Software Foundation; either |
| 9 | version 2.1 of the License, or (at your option) any later version. |
| 10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | Lesser General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU Lesser General Public |
| 17 | License along with the GNU C Library; if not, see |
| 18 | <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include <dlfcn.h> |
| 21 | |
| 22 | /* When one dynamically loads a module, which spawns a thread to perform some |
| 23 | activities, it could be possible that TLS storage is accessed for the first |
| 24 | time in that thread. This results in an allocation request within the |
| 25 | thread, which could result in an attempt to take the rtld load_lock. This |
| 26 | is a problem because it would then deadlock with the dlopen (which owns the |
| 27 | lock), if the main thread is waiting for the spawned thread to exit. We can |
| 28 | at least ensure that this problem does not occur due to accesses within |
| 29 | libc.so, by marking TLS variables within libc.so as IE. The problem of an |
| 30 | arbitrary variable being accessed and constructed within such a thread still |
| 31 | exists but this test case does not verify that. */ |
| 32 | |
| 33 | int |
| 34 | do_test (void) |
| 35 | { |
| 36 | void *f = dlopen ("tst-join7mod.so", RTLD_NOW | RTLD_GLOBAL); |
| 37 | if (f) |
| 38 | dlclose (f); |
| 39 | else |
| 40 | return 1; |
| 41 | |
| 42 | return 0; |
| 43 | } |
| 44 | |
| 45 | #define TEST_FUNCTION do_test () |
| 46 | #include "../test-skeleton.c" |