Fix for xen guest with mem > 3.7G

From: Roberto De Ioris
Date: Sat Sep 13 2008 - 15:24:22 EST

Xen domU kernel 2.6.26 and 2.6.27-rc cannot allocate
more than 3.7GB of ram on my PAE systems (compiled
with gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu7)).

I have found the problem is in function xen_memory_setup (in

It set max_pfn as 'unsigned long' but add_memory_region()
takes 'unsigned long long'.

I do not know if it is a compiler problem but this is the simple fix
(works on my systems):

--- setup.c.orig 2008-09-13 21:12:56.000000000 +0200
+++ setup.c 2008-09-13 20:35:29.000000000 +0200
@@ -36,7 +36,7 @@

char * __init xen_memory_setup(void)
- unsigned long max_pfn = xen_start_info->nr_pages;
+ unsigned long long max_pfn = xen_start_info->nr_pages;

e820.nr_map = 0;
add_memory_region(0, LOWMEMSIZE(), E820_RAM);

Roberto De Ioris
JID: roberto@xxxxxxxxxxxxxxx

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