diff --git a/valgrind-3.16.1-gdbserver_nlcontrolc.patch b/valgrind-3.16.1-gdbserver_nlcontrolc.patch
new file mode 100644
index 0000000..fbc7854
--- /dev/null
+++ b/valgrind-3.16.1-gdbserver_nlcontrolc.patch
@@ -0,0 +1,13 @@
+diff --git a/gdbserver_tests/nlcontrolc.vgtest b/gdbserver_tests/nlcontrolc.vgtest
+index bb5308403..4eb479595 100644
+--- a/gdbserver_tests/nlcontrolc.vgtest
++++ b/gdbserver_tests/nlcontrolc.vgtest
+@@ -13,7 +13,7 @@ args: 1000000000 1000000000 1000000000 BSBSBSBS 1
+ vgopts: --tool=none --vgdb=yes --vgdb-error=0 --vgdb-prefix=./vgdb-prefix-nlcontrolc
+ stderr_filter: filter_stderr
+ # Bug 338633 nlcontrol hangs on arm64 currently.
+-prereq: test -e gdb -a -f vgdb.invoker && ! ../tests/arch_test arm64 && ! ../tests/os_test solaris
++prereq: false && test -e gdb -a -f vgdb.invoker && ! ../tests/arch_test arm64 && ! ../tests/os_test solaris
+ progB: gdb
+ argsB: --quiet -l 60 --nx ./sleepers
+ stdinB: nlcontrolc.stdinB.gdb
diff --git a/valgrind.spec b/valgrind.spec
index f849b2a..63e4cea 100644
--- a/valgrind.spec
+++ b/valgrind.spec
@@ -108,6 +108,9 @@ Patch10: valgrind-3.16.1-dl_runtime_resolve.patch
 # KDE#427787  Support new faccessat2 linux syscall (439)
 Patch11: valgrind-3.16.1-faccessat2.patch
 
+# KDE#427931 gdbserver_tests/nlcontrolc.vgtest hangs on fedora rawhide
+Patch12: valgrind-3.16.1-gdbserver_nlcontrolc.patch
+
 BuildRequires: glibc-devel
 
 %if %{build_openmpi}
@@ -244,6 +247,7 @@ Valgrind User Manual for details.
 %patch9 -p1
 %patch10 -p1
 %patch11 -p1
+%patch12 -p1
 
 %build
 # LTO triggers undefined symbols in valgrind.  Valgrind has a --enable-lto
@@ -470,6 +474,7 @@ fi
 %changelog
 * Fri Oct 16 2020 Mark Wielaard <mjw@fedoraproject.org> - 3.16.1-6
 - Add valgrind-3.16.1-faccessat2.patch
+- Add valgrind-3.16.1-gdbserver_nlcontrolc.patch
 
 * Tue Aug 18 2020 Mark Wielaard <mjw@fedoraproject.org> - 3.16.1-5
 - Update valgrind-3.16.1-epoll.patch