v4.19.13 snapshot.
diff --git a/drivers/xen/xen-stub.c b/drivers/xen/xen-stub.c
new file mode 100644
index 0000000..bbef194
--- /dev/null
+++ b/drivers/xen/xen-stub.c
@@ -0,0 +1,100 @@
+/*
+ * xen-stub.c - stub drivers to reserve space for Xen
+ *
+ * Copyright (C) 2012 Intel Corporation
+ * Author: Liu Jinsong <jinsong.liu@intel.com>
+ * Author: Jiang Yunhong <yunhong.jiang@intel.com>
+ *
+ * Copyright (C) 2012 Oracle Inc
+ * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/acpi.h>
+#include <xen/acpi.h>
+
+#ifdef CONFIG_ACPI
+
+/*--------------------------------------------
+ stub driver for Xen memory hotplug
+--------------------------------------------*/
+
+static const struct acpi_device_id memory_device_ids[] = {
+ {ACPI_MEMORY_DEVICE_HID, 0},
+ {"", 0},
+};
+
+static struct acpi_driver xen_stub_memory_device_driver = {
+ /* same name as native memory driver to block native loaded */
+ .name = "acpi_memhotplug",
+ .class = ACPI_MEMORY_DEVICE_CLASS,
+ .ids = memory_device_ids,
+};
+
+int xen_stub_memory_device_init(void)
+{
+ if (!xen_initial_domain())
+ return -ENODEV;
+
+ /* just reserve space for Xen, block native driver loaded */
+ return acpi_bus_register_driver(&xen_stub_memory_device_driver);
+}
+EXPORT_SYMBOL_GPL(xen_stub_memory_device_init);
+subsys_initcall(xen_stub_memory_device_init);
+
+void xen_stub_memory_device_exit(void)
+{
+ acpi_bus_unregister_driver(&xen_stub_memory_device_driver);
+}
+EXPORT_SYMBOL_GPL(xen_stub_memory_device_exit);
+
+
+/*--------------------------------------------
+ stub driver for Xen cpu hotplug
+--------------------------------------------*/
+
+static const struct acpi_device_id processor_device_ids[] = {
+ {ACPI_PROCESSOR_OBJECT_HID, 0},
+ {ACPI_PROCESSOR_DEVICE_HID, 0},
+ {"", 0},
+};
+
+static struct acpi_driver xen_stub_processor_driver = {
+ /* same name as native processor driver to block native loaded */
+ .name = "processor",
+ .class = ACPI_PROCESSOR_CLASS,
+ .ids = processor_device_ids,
+};
+
+int xen_stub_processor_init(void)
+{
+ if (!xen_initial_domain())
+ return -ENODEV;
+
+ /* just reserve space for Xen, block native driver loaded */
+ return acpi_bus_register_driver(&xen_stub_processor_driver);
+}
+EXPORT_SYMBOL_GPL(xen_stub_processor_init);
+subsys_initcall(xen_stub_processor_init);
+
+void xen_stub_processor_exit(void)
+{
+ acpi_bus_unregister_driver(&xen_stub_processor_driver);
+}
+EXPORT_SYMBOL_GPL(xen_stub_processor_exit);
+
+#endif