From 3654581e47adc07072aebe239818485b68ea04f0 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 29 Sep 2010 16:54:33 -0700 Subject: [PATCH] xen: don't add extra_pages for RAM after mem_end If an E820 region is entirely beyond mem_end, don't attempt to truncate it and add the truncated pages to extra_pages, as they will be negative. Also, make sure the extra memory region starts after all BIOS provided E820 regions (and in the case of RAM regions, post-clipping). Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/setup.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index cad2fcd130ec..7a4ab05cff8a 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -52,20 +52,19 @@ phys_addr_t xen_extra_mem_start, xen_extra_mem_size; static __init void xen_add_extra_mem(unsigned long pages) { u64 size = (u64)pages * PAGE_SIZE; + u64 extra_start = xen_extra_mem_start + xen_extra_mem_size; if (!pages) return; - e820_add_region(xen_extra_mem_start + xen_extra_mem_size, size, E820_RAM); + e820_add_region(extra_start, size, E820_RAM); sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); - reserve_early(xen_extra_mem_start + xen_extra_mem_size, - xen_extra_mem_start + xen_extra_mem_size + size, - "XEN EXTRA"); + reserve_early(extra_start, extra_start + size, "XEN EXTRA"); xen_extra_mem_size += size; - xen_max_p2m_pfn = PFN_DOWN(xen_extra_mem_start + xen_extra_mem_size); + xen_max_p2m_pfn = PFN_DOWN(extra_start + size); } static unsigned long __init xen_release_chunk(phys_addr_t start_addr, @@ -175,15 +174,21 @@ char * __init xen_memory_setup(void) unsigned long long end = map[i].addr + map[i].size; if (map[i].type == E820_RAM) { - if (end > mem_end) { + if (map[i].addr < mem_end && end > mem_end) { /* Truncate region to max_mem. */ - map[i].size -= end - mem_end; + u64 delta = end - mem_end; - extra_pages += PFN_DOWN(end - mem_end); + map[i].size -= delta; + extra_pages += PFN_DOWN(delta); + + end = mem_end; } - } else if (map[i].type != E820_RAM) + } + + if (end > xen_extra_mem_start) xen_extra_mem_start = end; + /* If region is non-RAM or below mem_end, add what remains */ if ((map[i].type != E820_RAM || map[i].addr < mem_end) && map[i].size > 0) e820_add_region(map[i].addr, map[i].size, map[i].type);