diff --git a/test/CXX/symex/libc++/can_catch_test.cpp b/test/CXX/symex/libc++/can_catch_test.cpp
index c70d14a2aa..7515ef33d8 100644
--- a/test/CXX/symex/libc++/can_catch_test.cpp
+++ b/test/CXX/symex/libc++/can_catch_test.cpp
@@ -1,3 +1,5 @@
+// REQUIRES: not-msan
+// Disabling msan because it times out on CI
 // REQUIRES: uclibc
 // REQUIRES: libcxx
 // REQUIRES: eh-cxx
diff --git a/test/CXX/symex/libc++/exception_inheritance.cpp b/test/CXX/symex/libc++/exception_inheritance.cpp
index ca207eb4be..e24be60da2 100644
--- a/test/CXX/symex/libc++/exception_inheritance.cpp
+++ b/test/CXX/symex/libc++/exception_inheritance.cpp
@@ -1,3 +1,5 @@
+// REQUIRES: not-msan
+// Disabling msan because it times out on CI
 // REQUIRES: uclibc
 // REQUIRES: libcxx
 // REQUIRES: eh-cxx
diff --git a/test/CXX/symex/libc++/landingpad.cpp b/test/CXX/symex/libc++/landingpad.cpp
index 13dd6bc47a..6e8b13bcd6 100644
--- a/test/CXX/symex/libc++/landingpad.cpp
+++ b/test/CXX/symex/libc++/landingpad.cpp
@@ -1,3 +1,5 @@
+// REQUIRES: not-msan
+// Disabling msan because it times out on CI
 // Testcase for proper handling of
 // c++ type, constructors and destructors.
 // Based on: https://gcc.gnu.org/wiki/Dwarf2EHNewbiesHowto
diff --git a/test/CXX/symex/libc++/rethrow.cpp b/test/CXX/symex/libc++/rethrow.cpp
index 149fe693d5..febdf0b3e9 100644
--- a/test/CXX/symex/libc++/rethrow.cpp
+++ b/test/CXX/symex/libc++/rethrow.cpp
@@ -1,3 +1,5 @@
+// REQUIRES: not-msan
+// Disabling msan because it times out on CI
 // REQUIRES: uclibc
 // REQUIRES: libcxx
 // REQUIRES: eh-cxx
diff --git a/test/CXX/symex/libc++/throw_specifiers.cpp b/test/CXX/symex/libc++/throw_specifiers.cpp
index 96195cd498..6eae7f3abd 100644
--- a/test/CXX/symex/libc++/throw_specifiers.cpp
+++ b/test/CXX/symex/libc++/throw_specifiers.cpp
@@ -1,3 +1,5 @@
+// REQUIRES: not-msan
+// Disabling msan because it times out on CI
 // Testcase for proper handling of
 // throw specifications on functions
 // REQUIRES: uclibc
diff --git a/test/CXX/symex/libc++/throwing_exception_destructor.cpp b/test/CXX/symex/libc++/throwing_exception_destructor.cpp
index 02d7cdb920..f1e0e5d447 100644
--- a/test/CXX/symex/libc++/throwing_exception_destructor.cpp
+++ b/test/CXX/symex/libc++/throwing_exception_destructor.cpp
@@ -1,3 +1,5 @@
+// REQUIRES: not-msan
+// Disabling msan because it times out on CI
 // Testcase for proper handling of exception destructors that throw.
 // REQUIRES: uclibc
 // REQUIRES: libcxx