diff options
| author | Edward Liaw <edliaw@google.com> | 2024-10-18 17:17:24 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-10-28 21:40:41 -0700 |
| commit | f2330b650e97a68c1afce66305f10651a9544037 (patch) | |
| tree | 71ecec89472e2496b39b8dab93af2a88edc3876d /tools | |
| parent | 3673167a3a07f25b3f06754d69f406edea65543a (diff) | |
selftests/mm: fix deadlock for fork after pthread_create with atomic_bool
Some additional synchronization is needed on Android ARM64; we see a
deadlock with pthread_create when the parent thread races forward before
the child has a chance to start doing work.
Link: https://lkml.kernel.org/r/20241018171734.2315053-4-edliaw@google.com
Fixes: cff294582798 ("selftests/mm: extend and rename uffd pagemap test")
Signed-off-by: Edward Liaw <edliaw@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@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 | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c index b3d21eed203d..a2e71b1636e7 100644 --- a/tools/testing/selftests/mm/uffd-unit-tests.c +++ b/tools/testing/selftests/mm/uffd-unit-tests.c @@ -241,6 +241,8 @@ static void *fork_event_consumer(void *data) fork_event_args *args = data; struct uffd_msg msg = { 0 }; + ready_for_fork = true; + /* Read until a full msg received */ while (uffd_read_msg(args->parent_uffd, &msg)); @@ -308,8 +310,11 @@ static int pagemap_test_fork(int uffd, bool with_event, bool test_pin) /* Prepare a thread to resolve EVENT_FORK */ if (with_event) { + ready_for_fork = false; if (pthread_create(&thread, NULL, fork_event_consumer, &args)) err("pthread_create()"); + while (!ready_for_fork) + ; /* Wait for the poll_thread to start executing before forking */ } child = fork(); |