Index: drivers/input/i8042prt/pnp.c
===================================================================
--- drivers/input/i8042prt/pnp.c	(revision 74212)
+++ drivers/input/i8042prt/pnp.c	(working copy)
@@ -324,9 +324,16 @@
         return Status;
 
     PortDeviceExtension = DeviceExtension->Common.PortDeviceExtension;
-    DirqlMax = MAX(
-        PortDeviceExtension->KeyboardInterrupt.Dirql,
-        PortDeviceExtension->MouseInterrupt.Dirql);
+    if (PortDeviceExtension->HighestDIRQLInterrupt)
+    {
+        DirqlMax = MAX(
+            PortDeviceExtension->KeyboardInterrupt.Dirql,
+            PortDeviceExtension->MouseInterrupt.Dirql);
+    }
+    else
+    {
+        DirqlMax = PortDeviceExtension->MouseInterrupt.Dirql;
+    }
 
     INFO_(I8042PRT, "MouseInterrupt.Vector         %lu\n",
         PortDeviceExtension->MouseInterrupt.Vector);
@@ -477,16 +484,20 @@
             WARN_(I8042PRT, "i8042ConnectMouseInterrupt failed: %lx\n", Status);
         }
 
-        /* Start the mouse */
-        Irql = KeAcquireInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt);
         /* HACK: the mouse has already been reset in i8042DetectMouse. This second
            reset prevents some touchpads/mice from working (Dell D531, D600).
            See CORE-6901 */
         if (!(i8042HwFlags & FL_INITHACK))
         {
+            /* Start the mouse */
+            Irql = KeAcquireInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt);
             i8042IsrWritePort(DeviceExtension, MOU_CMD_RESET, CTRL_WRITE_MOUSE);
+            KeReleaseInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt, Irql);
         }
-        KeReleaseInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt, Irql);
+        else
+        {
+            WARN_(I8042PRT, "Skip mouse reset, because FL_INITHACK hardware is detected\n");
+        }
     }
 
     return Status;