[RFC PATCH] ARM 32: Workaround for memory problem >1gb on last section

[Frediano Ziglio <freddy77@gmail.com>]

setup_xenheap_mappings setup head memory on Arm 32 has a limit of 1GB.
On system with large memory is possible that there are no blocks of memory
smaller than 1gb leading xenheap_pages to be more than 1gb.
This cause memory errors trying to access heap after the 1gb limit.

I actually consider this patch as RFC as the pages are allocated at the end
of the block found however I don't think is safe to assume that the end is
aligned to 32mb as required.

Signed-off-by: Frediano Ziglio <frediano.ziglio@huawei.com>
---
 xen/arch/arm/setup.c | 5 +++++
 1 file changed, 5 insertions(+)


diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 446de8a..34b55b4 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -524,6 +524,11 @@ static void __init setup_mm(unsigned long
dtb_paddr, size_t dtb_size)
     if ( ! e )
         panic("Not not enough space for xenheap");

+#ifdef CONFIG_ARM_32
+    if ( xenheap_pages > 1<<(30-PAGE_SHIFT) )
+        xenheap_pages = 1<<(30-PAGE_SHIFT);
+#endif
+
     domheap_pages = heap_pages - xenheap_pages;

     printk("Xen heap: %"PRIpaddr"-%"PRIpaddr" (%lu pages)\n",
--
1.9.1