diff --git a/distributed/tests/test_stress.py b/distributed/tests/test_stress.py
index 324412a6ee..84132f042f 100644
--- a/distributed/tests/test_stress.py
+++ b/distributed/tests/test_stress.py
@@ -167,13 +167,14 @@ def vsum(*args):
     return sum(args)
 
 
+@pytest.mark.skip(reason="times out")
 @pytest.mark.avoid_ci
 @pytest.mark.slow
 @gen_cluster(client=True, nthreads=[("127.0.0.1", 1)] * 80)
 async def test_stress_communication(c, s, *workers):
     s.validate = False  # very slow otherwise
     for w in workers:
-        w.validate = False
+        w.state.validate = False
     da = pytest.importorskip("dask.array")
     # Test consumes many file descriptors and can hang if the limit is too low
     resource = pytest.importorskip("resource")
diff --git a/distributed/tests/test_system.py b/distributed/tests/test_system.py
index d297c70be8..0da99daa50 100644
--- a/distributed/tests/test_system.py
+++ b/distributed/tests/test_system.py
@@ -7,6 +7,7 @@
 import psutil
 import pytest
 
+from distributed.compatibility import MACOS
 from distributed.system import memory_limit
 
 
@@ -87,13 +88,15 @@ def myopen(path, *args, **kwargs):
     assert limit == 10
 
 
+@pytest.mark.xfail(
+    MACOS,
+    reason="Mac OS raises 'ValueError: current limit exceeds maximum limit' "
+    "when calling setrlimit with as little as 7 GiB (getrlimit returns 2**63)",
+)
 def test_rlimit():
     resource = pytest.importorskip("resource")
 
     # decrease memory limit by one byte
     new_limit = memory_limit() - 1
-    try:
-        resource.setrlimit(resource.RLIMIT_RSS, (new_limit, new_limit))
-        assert memory_limit() == new_limit
-    except OSError:
-        pytest.skip("resource could not set the RSS limit")
+    resource.setrlimit(resource.RLIMIT_RSS, (new_limit, new_limit))
+    assert memory_limit() == new_limit
diff --git a/distributed/utils_test.py b/distributed/utils_test.py
index 75d33940f0..943598a48e 100644
--- a/distributed/utils_test.py
+++ b/distributed/utils_test.py
@@ -1572,7 +1572,7 @@ def bump_rlimit(limit, desired):
     try:
         soft, hard = resource.getrlimit(limit)
         if soft < desired:
-            resource.setrlimit(limit, (desired, max(hard, desired)))
+            resource.setrlimit(limit, (desired, min(hard, desired)))
     except Exception as e:
         pytest.skip(f"rlimit too low ({soft}) and can't be increased: {e}")