diff --git a/linux-user/ioctls.h b/linux-user/ioctls.h
index bc19448042..b253469999 100644
--- a/linux-user/ioctls.h
+++ b/linux-user/ioctls.h
@@ -112,6 +112,8 @@
      IOCTL(BLKZEROOUT, IOC_W, MK_PTR(MK_ARRAY(TYPE_ULONGLONG, 2)))
 #endif
 
+     IOCTL(FDMSGON, 0, TYPE_NULL)
+     IOCTL(FDMSGOFF, 0, TYPE_NULL)
      IOCTL(FDFLUSH, 0, TYPE_NULL)
 
 #ifdef FIBMAP
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 917202a203..4e33ef396b 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -890,6 +890,8 @@ struct target_pollfd {
 
 /* From <linux/fd.h> */
 
+#define TARGET_FDMSGON        TARGET_IO(2, 0x45)
+#define TARGET_FDMSGOFF       TARGET_IO(2, 0x46)
 #define TARGET_FDFLUSH        TARGET_IO(2, 0x4b)
 
 #define TARGET_FIBMAP     TARGET_IO(0x00,1)  /* bmap access */