Move CRASH_ALIGN to header asm/kexec.h for later use. Besides, the
alignment of crash kernel regions in x86 is 16M(CRASH_ALIGN), but
function reserve_crashkernel() also used 1M alignment. So just
replace hard-coded alignment 1M with macro CRASH_ALIGN.

Suggested-by: Dave Young <redacted>
Suggested-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Chen Zhou <redacted>
Tested-by: John Donnelly <redacted>
---
 arch/x86/include/asm/kexec.h | 3 +++
 arch/x86/kernel/setup.c      | 5 +----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index 6802c59e8252..be18dc7ae51f 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h

@@ -18,6 +18,9 @@
 
 # define KEXEC_CONTROL_CODE_MAX_SIZE	2048
 
+/* 16M alignment for crash kernel regions */
+#define CRASH_ALIGN		SZ_16M
+
 #ifndef __ASSEMBLY__
 
 #include <linux/string.h>

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 3412c4595efd..da769845597d 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c

@@ -390,9 +390,6 @@ static void __init memblock_x86_reserve_range_setup_data(void)
 
 #ifdef CONFIG_KEXEC_CORE
 
-/* 16M alignment for crash kernel regions */
-#define CRASH_ALIGN		SZ_16M
-
 /*
  * Keep the crash kernel below this limit.
  *

@@ -510,7 +507,7 @@ static void __init reserve_crashkernel(void)
 	} else {
 		unsigned long long start;
 
-		start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
+		start = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, crash_base,
 						  crash_base + crash_size);