x86: make max_pfn cover acpi table below 4g
When system have 4g less ram installed, and acpi table sit
near end of ram, make max_pfn cover them too,
so 64bit kernel don't need to mess up fixmap.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: "Suresh Siddha" <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index e07d401..2e08619 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1056,12 +1056,20 @@
/*
* Find the highest page frame number we have available
*/
-unsigned long __init e820_end_of_ram(void)
+unsigned long __init e820_end(void)
{
- unsigned long last_pfn;
+ int i;
+ unsigned long last_pfn = 0;
unsigned long max_arch_pfn = MAX_ARCH_PFN;
- last_pfn = find_max_pfn_with_active_regions();
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *ei = &e820.map[i];
+ unsigned long end_pfn;
+
+ end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
+ if (end_pfn > last_pfn)
+ last_pfn = end_pfn;
+ }
if (last_pfn > max_arch_pfn)
last_pfn = max_arch_pfn;
@@ -1192,9 +1200,7 @@
* the real mem size before original memory map is
* reset.
*/
- e820_register_active_regions(0, 0, -1UL);
- saved_max_pfn = e820_end_of_ram();
- remove_all_active_ranges();
+ saved_max_pfn = e820_end();
#endif
e820.nr_map = 0;
userdef = 1;