diff --git a/include/uv.h b/include/uv.h
index 379c538a..16f847c2 100644
--- a/include/uv.h
+++ b/include/uv.h
@@ -1074,8 +1074,11 @@ UV_EXTERN int uv_tty_set_mode(uv_tty_t*, int mode);
 /*
  * To be called when the program exits. Resets TTY settings to default
  * values for the next process to take over.
+ *
+ * This function is async signal-safe on UNIX platforms but can fail with error
+ * code UV_EBUSY if you call it when execution is inside uv_tty_set_mode().
  */
-UV_EXTERN void uv_tty_reset_mode(void);
+UV_EXTERN int uv_tty_reset_mode(void);
 
 /*
  * Gets the current Window size. On success zero is returned.
diff --git a/src/unix/tty.c b/src/unix/tty.c
index 2fe57476..ca9459dd 100644
--- a/src/unix/tty.c
+++ b/src/unix/tty.c
@@ -21,6 +21,7 @@
 
 #include "uv.h"
 #include "internal.h"
+#include "spinlock.h"
 
 #include <assert.h>
 #include <unistd.h>
@@ -28,9 +29,9 @@
 #include <errno.h>
 #include <sys/ioctl.h>
 
-
 static int orig_termios_fd = -1;
 static struct termios orig_termios;
+static uv_spinlock_t termios_spinlock = UV_SPINLOCK_INITIALIZER;
 
 
 int uv_tty_init(uv_loop_t* loop, uv_tty_t* tty, int fd, int readable) {
@@ -69,10 +70,12 @@ int uv_tty_set_mode(uv_tty_t* tty, int mode) {
       return -errno;
 
     /* This is used for uv_tty_reset_mode() */
+    uv_spinlock_lock(&termios_spinlock);
     if (orig_termios_fd == -1) {
       orig_termios = tty->orig_termios;
       orig_termios_fd = fd;
     }
+    uv_spinlock_unlock(&termios_spinlock);
 
     raw = tty->orig_termios;
     raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
@@ -161,8 +164,21 @@ uv_handle_type uv_guess_handle(uv_file file) {
 }
 
 
-void uv_tty_reset_mode(void) {
-  if (orig_termios_fd >= 0) {
-    tcsetattr(orig_termios_fd, TCSANOW, &orig_termios);
-  }
+/* This function is async signal-safe, meaning that it's safe to call from
+ * inside a signal handler _unless_ execution was inside uv_tty_set_mode()'s
+ * critical section when the signal was raised.
+ */
+int uv_tty_reset_mode(void) {
+  int err;
+
+  if (!uv_spinlock_trylock(&termios_spinlock))
+    return -EBUSY;  /* In uv_tty_set_mode(). */
+
+  err = 0;
+  if (orig_termios_fd != -1)
+    if (tcsetattr(orig_termios_fd, TCSANOW, &orig_termios))
+      err = -errno;
+
+  uv_spinlock_unlock(&termios_spinlock);
+  return err;
 }
diff --git a/src/win/tty.c b/src/win/tty.c
index d380cd0b..4f9cfa56 100644
--- a/src/win/tty.c
+++ b/src/win/tty.c
@@ -1866,7 +1866,7 @@ void uv_process_tty_connect_req(uv_loop_t* loop, uv_tty_t* handle,
 }
 
 
-void uv_tty_reset_mode(void) {
+int uv_tty_reset_mode(void) {
   /* Not necessary to do anything. */
-  ;
+  return 0;
 }