diff options
| author | Edward Liaw <edliaw@google.com> | 2024-10-03 21:17:11 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-10-17 00:28:06 -0700 |
| commit | e142cc87ac4ec618f2ccf5f68aedcd6e28a59d9d (patch) | |
| tree | 6e9f811f617b6d76045b48fd64f5d1547e919428 /tools | |
| parent | e61ef21e27e8deed8c474e9f47f4aa7bc37e138c (diff) | |
selftests/mm: fix deadlock for fork after pthread_create on ARM
On Android with arm, there is some synchronization needed to avoid a
deadlock when forking after pthread_create.
Link: https://lkml.kernel.org/r/20241003211716.371786-3-edliaw@google.com
Fixes: cff294582798 ("selftests/mm: extend and rename uffd pagemap test")
Signed-off-by: Edward Liaw <edliaw@google.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/mm/uffd-unit-tests.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c index 3db2296ac631..c8a3b1c7edff 100644 --- a/tools/testing/selftests/mm/uffd-unit-tests.c +++ b/tools/testing/selftests/mm/uffd-unit-tests.c @@ -241,6 +241,9 @@ static void *fork_event_consumer(void *data) fork_event_args *args = data; struct uffd_msg msg = { 0 }; + /* Ready for parent thread to fork */ + pthread_barrier_wait(&ready_for_fork); + /* Read until a full msg received */ while (uffd_read_msg(args->parent_uffd, &msg)); @@ -308,8 +311,12 @@ static int pagemap_test_fork(int uffd, bool with_event, bool test_pin) /* Prepare a thread to resolve EVENT_FORK */ if (with_event) { + pthread_barrier_init(&ready_for_fork, NULL, 2); if (pthread_create(&thread, NULL, fork_event_consumer, &args)) err("pthread_create()"); + /* Wait for child thread to start before forking */ + pthread_barrier_wait(&ready_for_fork); + pthread_barrier_destroy(&ready_for_fork); } child = fork(); |