x86: trim mtrr don't close gap for resource allocation.

fix the bug reported here:

	http://bugzilla.kernel.org/show_bug.cgi?id=10232

use update_memory_range() instead of add_memory_range() directly
to avoid closing the gap.

( the new code only affects and runs on systems where the MTRR
  workaround triggers. )

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index be83336fddba..a6450b3ae759 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -711,7 +711,8 @@ int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
                 trim_size = end_pfn;
                 trim_size <<= PAGE_SHIFT;
                 trim_size -= trim_start;
-                add_memory_region(trim_start, trim_size, E820_RESERVED);
+                update_memory_range(trim_start, trim_size, E820_RAM,
+                                        E820_RESERVED);
                 update_e820();
                 return 1;
         }