[LINUX] /proc/iomem should not be initialised from pseudophysical e820 map.

This is because it should only contain real I/O memory address ranges,
otherwise we can get false conflicts between a real I/O range and a
'pseudophysical' RAM range, causing drivers to fail to work in a domU.
Also prevent kernel code/data being requested as iomem resources --
they are not contiguous in 'io memory' space so this would not make
sense.

Signed-off-by: Keir Fraser <keir@xensource.com>

linux-2.6-xen-sparse/arch/i386/kernel/setup-xen.c

@@ -1380,8 +1380,10 @@ legacy_init_iomem_resources(struct e820entry *e820, int nr_map,
 			 *  so we try it repeatedly and let the resource manager
 			 *  test it.
 			 */
+#ifndef CONFIG_XEN
 			request_resource(res, code_resource);
 			request_resource(res, data_resource);
+#endif
 #ifdef CONFIG_KEXEC
 			request_resource(res, &crashk_res);
 #endif
@@ -1454,11 +1456,8 @@ static void __init register_memory(void)
 	int	      i;
 
 	/* Nothing to do if not running in dom0. */
-	if (!is_initial_xendomain()) {
-		legacy_init_iomem_resources(e820.map, e820.nr_map,
-					    &code_resource, &data_resource);
+	if (!is_initial_xendomain())
 		return;
-	}
 
 #ifdef CONFIG_XEN
 	machine_e820 = alloc_bootmem_low_pages(PAGE_SIZE);

linux-2.6-xen-sparse/arch/x86_64/kernel/e820-xen.c

@@ -255,8 +255,10 @@ void __init e820_reserve_resources(struct e820entry *e820, int nr_map)
 			 *  so we try it repeatedly and let the resource manager
 			 *  test it.
 			 */
+#ifndef CONFIG_XEN
 			request_resource(res, &code_resource);
 			request_resource(res, &data_resource);
+#endif
 #ifdef CONFIG_KEXEC
 			request_resource(res, &crashk_res);
 #endif

linux-2.6-xen-sparse/arch/x86_64/kernel/setup-xen.c

@@ -944,9 +944,10 @@ void __init setup_arch(char **cmdline_p)
 		BUG_ON(HYPERVISOR_memory_op(XENMEM_machine_memory_map, &memmap));
 
 		e820_reserve_resources(machine_e820, memmap.nr_entries);
-	} else
-#endif
+	}
+#else
 	e820_reserve_resources(e820.map, e820.nr_map);
+#endif
 
 	request_resource(&iomem_resource, &video_ram_resource);