diff --git a/chardev/char.c b/chardev/char.c
index ea06c5ff4d..e3051295ac 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -38,6 +38,7 @@
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "qemu/id.h"
+#include "qemu/coroutine.h"
 
 #include "chardev/char-mux.h"
 
@@ -119,7 +120,11 @@ static int qemu_chr_write_buffer(Chardev *s,
     retry:
         res = cc->chr_write(s, buf + *offset, len - *offset);
         if (res < 0 && errno == EAGAIN && write_all) {
-            g_usleep(100);
+            if (qemu_in_coroutine()) {
+                qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000);
+            } else {
+                g_usleep(100);
+            }
             goto retry;
         }