diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 471d0605f7..c6a6337426 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6888,6 +6888,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
         ret = get_errno(do_fork(cpu_env, arg1, arg2, arg3, arg5, arg4));
 #elif defined(TARGET_CRIS)
         ret = get_errno(do_fork(cpu_env, arg2, arg1, arg3, arg4, arg5));
+#elif defined(TARGET_MICROBLAZE)
+        ret = get_errno(do_fork(cpu_env, arg1, arg2, arg4, arg6, arg5));
 #elif defined(TARGET_S390X)
         ret = get_errno(do_fork(cpu_env, arg2, arg1, arg3, arg5, arg4));
 #else
diff --git a/target-microblaze/cpu.h b/target-microblaze/cpu.h
index 4968c244e8..88430b5057 100644
--- a/target-microblaze/cpu.h
+++ b/target-microblaze/cpu.h
@@ -345,6 +345,7 @@ static inline void cpu_clone_regs(CPUMBState *env, target_ulong newsp)
 
 static inline void cpu_set_tls(CPUMBState *env, target_ulong newtls)
 {
+    env->regs[21] = newtls;
 }
 
 static inline int cpu_interrupts_enabled(CPUMBState *env)