diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 389ec09..9522f60 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6481,6 +6481,16 @@
         /* Grab a mutex so that thread setup appears atomic.  */
         pthread_mutex_lock(&clone_lock);
 
+        /*
+         * If this is our first additional thread, we need to ensure we
+         * generate code for parallel execution and flush old translations.
+         * Do this now so that the copy gets CF_PARALLEL too.
+         */
+        if (!(cpu->tcg_cflags & CF_PARALLEL)) {
+            cpu->tcg_cflags |= CF_PARALLEL;
+            tb_flush(cpu);
+        }
+
         /* we create a new CPU instance. */
         new_env = cpu_copy(env);
         /* Init regs that differ from the parent.  */
@@ -6521,14 +6531,6 @@
         sigprocmask(SIG_BLOCK, &sigmask, &info.sigmask);
         cpu->random_seed = qemu_guest_random_seed_thread_part1();
 
-        /* If this is our first additional thread, we need to ensure we
-         * generate code for parallel execution and flush old translations.
-         */
-        if (!parallel_cpus) {
-            parallel_cpus = true;
-            tb_flush(cpu);
-        }
-
         ret = pthread_create(&info.thread, &attr, clone_func, &info);
         /* TODO: Free new CPU state if thread creation failed.  */