[GIT PULL] x86 fix

[Ingo Molnar <mingo@elte.hu>]

Linus,

Please pull the latest x86-fixes-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git x86-fixes-for-linus

 Thanks,

	Ingo

------------------>
H. Peter Anvin (1):
      x86, kexec: Limit the crashkernel address appropriately


 arch/x86/kernel/setup.c |   17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 21c6746..c9089a1 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -501,7 +501,18 @@ static inline unsigned long long get_total_mem(void)
 	return total << PAGE_SHIFT;
 }
 
-#define DEFAULT_BZIMAGE_ADDR_MAX 0x37FFFFFF
+/*
+ * Keep the crash kernel below this limit.  On 32 bits earlier kernels
+ * would limit the kernel to the low 512 MiB due to mapping restrictions.
+ * On 64 bits, kexec-tools currently limits us to 896 MiB; increase this
+ * limit once kexec-tools are fixed.
+ */
+#ifdef CONFIG_X86_32
+# define CRASH_KERNEL_ADDR_MAX	(512 << 20)
+#else
+# define CRASH_KERNEL_ADDR_MAX	(896 << 20)
+#endif
+
 static void __init reserve_crashkernel(void)
 {
 	unsigned long long total_mem;
@@ -520,10 +531,10 @@ static void __init reserve_crashkernel(void)
 		const unsigned long long alignment = 16<<20;	/* 16M */
 
 		/*
-		 *  kexec want bzImage is below DEFAULT_BZIMAGE_ADDR_MAX
+		 *  kexec want bzImage is below CRASH_KERNEL_ADDR_MAX
 		 */
 		crash_base = memblock_find_in_range(alignment,
-			       DEFAULT_BZIMAGE_ADDR_MAX, crash_size, alignment);
+			       CRASH_KERNEL_ADDR_MAX, crash_size, alignment);
 
 		if (crash_base == MEMBLOCK_ERROR) {
 			pr_info("crashkernel reservation failed - No suitable area found.\n");