[PATCH v18 08/17] x86/setup: Add build option ARCH_WANT_RESERVE_CRASH_KERNEL

[Zhen Lei]

From: Chen Zhou <chenzhou10 at huawei.com>

There are multiple ARCHs that implement reserve_crashkernel(), all of them
are marked as static. Currently, we want to combine the implementations on
x86 and arm64 into one, and move it to public crash_core.c. To avoid
symbol conflicts on other platforms, add a new build option
ARCH_WANT_RESERVE_CRASH_KERNEL. And change CONFIG_X86_64 to CONFIG_64BIT,
so it can be shared with arm64, or other users in future.

Signed-off-by: Chen Zhou <chenzhou10 at huawei.com>
Co-developed-by: Zhen Lei <thunder.leizhen at huawei.com>
Signed-off-by: Zhen Lei <thunder.leizhen at huawei.com>
---
 arch/Kconfig            |  3 +++
 arch/x86/Kconfig        |  2 ++
 arch/x86/kernel/setup.c | 10 +++++-----
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index d3c4ab249e9c275..f53dd7852290b9a 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -11,6 +11,9 @@ source "arch/$(SRCARCH)/Kconfig"
 
 menu "General architecture-dependent options"
 
+config ARCH_WANT_RESERVE_CRASH_KERNEL
+	bool
+
 config CRASH_CORE
 	bool
 
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5c2ccb85f2efb86..bd78ed8193079b9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -12,6 +12,7 @@ config X86_32
 	depends on !64BIT
 	# Options that are inherently 32-bit kernel only:
 	select ARCH_WANT_IPC_PARSE_VERSION
+	select ARCH_WANT_RESERVE_CRASH_KERNEL if KEXEC_CORE
 	select CLKSRC_I8253
 	select CLONE_BACKWARDS
 	select GENERIC_VDSO_32
@@ -28,6 +29,7 @@ config X86_64
 	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
 	select ARCH_USE_CMPXCHG_LOCKREF
+	select ARCH_WANT_RESERVE_CRASH_KERNEL if KEXEC_CORE
 	select HAVE_ARCH_SOFT_DIRTY
 	select MODULES_USE_ELF_RELA
 	select NEED_DMA_MAP_STATE
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index abff57ffbe92884..beb73cce4b8b826 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -390,9 +390,9 @@ static void __init memblock_x86_reserve_range_setup_data(void)
  * --------- Crashkernel reservation ------------------------------
  */
 
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL
 
-#ifdef CONFIG_X86_64
+#ifdef CONFIG_64BIT
 static int __init reserve_crashkernel_low(unsigned long long low_size)
 {
 	unsigned long long low_base = 0;
@@ -456,7 +456,7 @@ static int __init parse_crashkernel_in_order(char *cmdline,
 	if (!ret && crash_size > 0)
 		return CRASHKERNEL_MEM_CLASSIC;
 
-#ifdef CONFIG_X86_64
+#ifdef CONFIG_64BIT
 	/* crashkernel=X,high */
 	ret = parse_crashkernel_high(cmdline, system_ram, crash_size, crash_base);
 	if (ret || crash_size <= 0)
@@ -522,7 +522,7 @@ static void __init reserve_crashkernel(void)
 		}
 	}
 
-#ifdef CONFIG_X86_64
+#ifdef CONFIG_64BIT
 	if (crash_base >= CRASH_ADDR_LOW_MAX) {
 		/*
 		 * Ensure that at least 256M extra low memory is allocated for
@@ -556,7 +556,7 @@ static void __init reserve_crashkernel(void)
 	crashk_res.start = crash_base;
 	crashk_res.end   = crash_base + crash_size - 1;
 }
-#endif
+#endif	/* CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL */
 
 static struct resource standard_io_resources[] = {
 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
-- 
2.25.1