x86: update mptable

make mptable to be consistent with acpi routing, so we could:

1. kexec kernel with acpi=off
2. work around BIOSes where acpi routing is working, but mptable is
   not right, so can use kernel/kexec to start other OSes that don't have
   good acpi support.

command line: update_mptable

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

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index 89e6cca5d693..978a0d637f3f 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -56,6 +56,7 @@
 #include <asm/desc.h>
 #include <video/edid.h>
 #include <asm/e820.h>
+#include <asm/mpspec.h>
 #include <asm/dma.h>
 #include <asm/gart.h>
 #include <asm/mpspec.h>
@@ -381,6 +382,9 @@ void __init setup_arch(char **cmdline_p)
          * we are rounding upwards:
          */
         end_pfn = e820_end_of_ram();
+
+        /* pre allocte 4k for mptable mpc */
+        early_reserve_e820_mpc_new();
         /* update e820 for memory not covered by WB MTRRs */
         mtrr_bp_init();
         if (mtrr_trim_uncached_memory(end_pfn)) {