diff --git a/dix/events.c b/dix/events.c
index 52c5e6c38..13ef5b871 100644
--- a/dix/events.c
+++ b/dix/events.c
@@ -3417,7 +3417,17 @@ CheckPassiveGrabsOnWindow(
                 gdev = GetPairedDevice(device);
             else
                 gdev = device;
+        } else if (grab->grabtype == GRABTYPE_XI2)
+        {
+            /* if the device is an attached slave device, gdev must be the
+             * attached master keyboard. Since the slave may have been
+             * reattached after the grab, the modifier device may not be the
+             * same. */
+            if (!IsMaster(grab->device) && device->u.master)
+                gdev = GetMaster(device, MASTER_KEYBOARD);
         }
+
+
         if (gdev && gdev->key)
             xkbi= gdev->key->xkbInfo;
 	tempGrab.modifierDevice = grab->modifierDevice;