diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c
index ba6777cdf423..3bdae35e0add 100644
--- a/tools/testing/selftests/mm/uffd-common.c
+++ b/tools/testing/selftests/mm/uffd-common.c
@@ -17,7 +17,7 @@ bool map_shared;
 bool test_uffdio_wp = true;
 unsigned long long *count_verify;
 uffd_test_ops_t *uffd_test_ops;
-atomic_bool ready_for_fork;
+pthread_barrier_t ready_for_fork;
 
 static int uffd_mem_fd_create(off_t mem_size, bool hugetlb)
 {
@@ -508,7 +508,8 @@ void *uffd_poll_thread(void *arg)
 	pollfd[1].fd = pipefd[cpu*2];
 	pollfd[1].events = POLLIN;
 
-	ready_for_fork = true;
+	/* Ready for parent thread to fork */
+	pthread_barrier_wait(&ready_for_fork);
 
 	for (;;) {
 		ret = poll(pollfd, 2, -1);
diff --git a/tools/testing/selftests/mm/uffd-common.h b/tools/testing/selftests/mm/uffd-common.h
index 2832669bd9fd..2d78ae0daf06 100644
--- a/tools/testing/selftests/mm/uffd-common.h
+++ b/tools/testing/selftests/mm/uffd-common.h
@@ -33,7 +33,6 @@
 #include <inttypes.h>
 #include <stdint.h>
 #include <sys/random.h>
-#include <stdatomic.h>
 
 #include "../kselftest.h"
 #include "vm_util.h"
@@ -99,7 +98,7 @@ extern bool map_shared;
 extern bool test_uffdio_wp;
 extern unsigned long long *count_verify;
 extern volatile bool test_uffdio_copy_eexist;
-extern atomic_bool ready_for_fork;
+extern pthread_barrier_t ready_for_fork;
 
 extern uffd_test_ops_t anon_uffd_test_ops;
 extern uffd_test_ops_t shmem_uffd_test_ops;
diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
index 92d51768b7be..d7bc740245ac 100644
--- a/tools/testing/selftests/mm/uffd-unit-tests.c
+++ b/tools/testing/selftests/mm/uffd-unit-tests.c
@@ -770,7 +770,7 @@ static void uffd_sigbus_test_common(bool wp)
 	char c;
 	struct uffd_args args = { 0 };
 
-	ready_for_fork = false;
+	pthread_barrier_init(&ready_for_fork, NULL, 2);
 
 	fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
 
@@ -787,8 +787,9 @@ static void uffd_sigbus_test_common(bool wp)
 	if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
 		err("uffd_poll_thread create");
 
-	while (!ready_for_fork)
-		; /* Wait for the poll_thread to start executing before forking */
+	/* Wait for child thread to start before forking */
+	pthread_barrier_wait(&ready_for_fork);
+	pthread_barrier_destroy(&ready_for_fork);
 
 	pid = fork();
 	if (pid < 0)
@@ -829,7 +830,7 @@ static void uffd_events_test_common(bool wp)
 	char c;
 	struct uffd_args args = { 0 };
 
-	ready_for_fork = false;
+	pthread_barrier_init(&ready_for_fork, NULL, 2);
 
 	fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
 	if (uffd_register(uffd, area_dst, nr_pages * page_size,
@@ -840,8 +841,9 @@ static void uffd_events_test_common(bool wp)
 	if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
 		err("uffd_poll_thread create");
 
-	while (!ready_for_fork)
-		; /* Wait for the poll_thread to start executing before forking */
+	/* Wait for child thread to start before forking */
+	pthread_barrier_wait(&ready_for_fork);
+	pthread_barrier_destroy(&ready_for_fork);
 
 	pid = fork();
 	if (pid < 0)