[Xen-changelog] [xen-unstable] [XEN] Limit size of Xen heap to 2GB.

[Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User kfraser@xxxxxxxxxxxxxxxxxxxxx
# Node ID ab2817b9547bf444331bda15adecf0bf8dec55a6
# Parent  83b53eeb8a5c5c453c206a13271ff9627db42380
[XEN] Limit size of Xen heap to 2GB.

Avoids stub code created on the stack being unable to
reach targets in main Xen code via direct branches.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
---
 xen/arch/x86/setup.c |    7 +++++++
 1 files changed, 7 insertions(+)

diff -r 83b53eeb8a5c -r ab2817b9547b xen/arch/x86/setup.c
--- a/xen/arch/x86/setup.c      Mon Sep 25 09:29:28 2006 +0100
+++ b/xen/arch/x86/setup.c      Mon Sep 25 09:31:11 2006 +0100
@@ -272,6 +272,13 @@ void __init __start_xen(multiboot_info_t
         EARLY_FAIL();
     }
 
+    /*
+     * Since there are some stubs getting built on the stacks which use
+     * direct calls/jumps, the heap must be confined to the lower 2G so
+     * that those branches can reach their targets.
+     */
+    if ( opt_xenheap_megabytes > 2048 )
+        opt_xenheap_megabytes = 2048;
     xenheap_phys_end = opt_xenheap_megabytes << 20;
 
     if ( mbi->flags & MBI_MEMMAP )

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog