Index: test/dosep.py
===================================================================
--- test/dosep.py
+++ test/dosep.py
@@ -251,6 +251,7 @@
             "TestExitDuringStep.py",
             "TestHelloWorld.py", # Times out in ~10% of the times on the build bot
             "TestMultithreaded.py",
+            "TestRegisters.py", # ~12/600 dosep runs (build 3120-3122)
             "TestThreadStepOut.py",
         }
     elif target.startswith("android"):
Index: test/tools/lldb-mi/TestMiGdbSetShow.py
===================================================================
--- test/tools/lldb-mi/TestMiGdbSetShow.py
+++ test/tools/lldb-mi/TestMiGdbSetShow.py
@@ -62,6 +62,7 @@
     @lldbmi_test
     @expectedFailureWindows("llvm.org/pr22274: need a pexpect replacement for windows")
     @skipIfFreeBSD # llvm.org/pr22411: Failure presumably due to known thread races
+    @expectedFailureLinux # Failing in ~11/600 dosep runs (build 3120-3122)
     def test_lldbmi_gdb_set_target_async_off(self):
         """Test that 'lldb-mi --interpreter' can execute commands in sync mode."""
 
Index: test/tools/lldb-mi/interpreter/TestMiInterpreterExec.py
===================================================================
--- test/tools/lldb-mi/interpreter/TestMiInterpreterExec.py
+++ test/tools/lldb-mi/interpreter/TestMiInterpreterExec.py
@@ -55,6 +55,7 @@
     @lldbmi_test
     @expectedFailureWindows("llvm.org/pr22274: need a pexpect replacement for windows")
     @skipIfFreeBSD # llvm.org/pr22411: Failure presumably due to known thread races
+    @expectedFailureLinux  # Failing in ~9/600 dosep runs (build 3120-3122)
     def test_lldbmi_settings_set_target_run_args_before(self):
         """Test that 'lldb-mi --interpreter' can set target arguments by 'setting set target.run-args' command before than target was created."""
 
@@ -79,6 +80,7 @@
     @lldbmi_test
     @expectedFailureWindows("llvm.org/pr22274: need a pexpect replacement for windows")
     @skipIfFreeBSD # llvm.org/pr22411: Failure presumably due to known thread races
+    @expectedFailureLinux  # Failing in ~9/600 dosep runs (build 3120-3122)
     def test_lldbmi_settings_set_target_run_args_after(self):
         """Test that 'lldb-mi --interpreter' can set target arguments by 'setting set target.run-args' command after than target was created."""
 
Index: test/tools/lldb-mi/syntax/TestMiSyntax.py
===================================================================
--- test/tools/lldb-mi/syntax/TestMiSyntax.py
+++ test/tools/lldb-mi/syntax/TestMiSyntax.py
@@ -61,6 +61,7 @@
     @lldbmi_test
     @expectedFailureWindows("llvm.org/pr22274: need a pexpect replacement for windows")
     @skipIfFreeBSD # llvm.org/pr22411: Failure presumably due to known thread races
+    @expectedFailureLinux  # Failing in ~6/600 dosep runs (build 3120-3122)
     def test_lldbmi_process_output(self):
         """Test that 'lldb-mi --interpreter' wraps process output correctly."""