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| author | Edward Liaw <edliaw@google.com> | 2024-03-25 19:40:52 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-03-26 11:14:12 -0700 |
| commit | 8c864371b2a15a23ce35aa7e2bd241baaad6fbe8 (patch) | |
| tree | da29bdeaeadebfdaf6907a7f7fc830d2049cbc37 /tools/testing/selftests/mm/uffd-common.c | |
| parent | 549aa9678a0b3981d4821bf244579d9937650562 (diff) | |
| download | linux-8c864371b2a15a23ce35aa7e2bd241baaad6fbe8.tar.gz | |
selftests/mm: fix ARM related issue with fork after pthread_create
Following issue was observed while running the uffd-unit-tests selftest
on ARM devices. On x86_64 no issues were detected:
pthread_create followed by fork caused deadlock in certain cases wherein
fork required some work to be completed by the created thread. Used
synchronization to ensure that created thread's start function has started
before invoking fork.
[edliaw@google.com: refactored to use atomic_bool]
Link: https://lkml.kernel.org/r/20240325194100.775052-1-edliaw@google.com
Fixes: 760aee0b71e3 ("selftests/mm: add tests for RO pinning vs fork()")
Signed-off-by: Lokesh Gidra <lokeshgidra@google.com>
Signed-off-by: Edward Liaw <edliaw@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'tools/testing/selftests/mm/uffd-common.c')
| -rw-r--r-- | tools/testing/selftests/mm/uffd-common.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c index b0ac0ec2356d65..7ad6ba660c7d6f 100644 --- a/tools/testing/selftests/mm/uffd-common.c +++ b/tools/testing/selftests/mm/uffd-common.c @@ -18,6 +18,7 @@ bool test_uffdio_wp = true; unsigned long long *count_verify; uffd_test_ops_t *uffd_test_ops; uffd_test_case_ops_t *uffd_test_case_ops; +atomic_bool ready_for_fork; static int uffd_mem_fd_create(off_t mem_size, bool hugetlb) { @@ -518,6 +519,8 @@ void *uffd_poll_thread(void *arg) pollfd[1].fd = pipefd[cpu*2]; pollfd[1].events = POLLIN; + ready_for_fork = true; + for (;;) { ret = poll(pollfd, 2, -1); if (ret <= 0) { |