diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 3ba07ce5f8..2792208366 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2017-09-05  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* remote.c (process_g_packet): Update error message.
+
 2017-09-05  Yao Qi  <yao.qi@linaro.org>
 
 	* configure.tgt (gdb_target_obs): Add i386.o for x86_64-*
diff --git a/gdb/remote.c b/gdb/remote.c
index 3347dd8022..abeef0d9fd 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -7591,7 +7591,8 @@ process_g_packet (struct regcache *regcache)
 
   /* Further sanity checks, with knowledge of the architecture.  */
   if (buf_len > 2 * rsa->sizeof_g_packet)
-    error (_("Remote 'g' packet reply is too long: %s"), rs->buf);
+    error (_("Remote 'g' packet reply is too long (expected %ld bytes, got %d "
+	     "bytes): %s"), rsa->sizeof_g_packet, buf_len / 2, rs->buf);
 
   /* Save the size of the packet sent to us by the target.  It is used
      as a heuristic when determining the max size of packets that the