[PATCH] x86_64/setup: handle builtin command line early

[Alexander Kuleshov]

We handle builtin command line during setup_arch() work of the
setup_arch(). But it may be useful to handle it earlier for
x86_64.

For example: x86_64 supports early update ucode from the
feddc9de (x86/head64.c: Early update ucode in 64-bit) commit by
the calling of load_ucode_bsp() which in turn checks 'dis_ucode_ldr'
option which may be passed through builtin command line.

Signed-off-by: Alexander Kuleshov <kuleshovmail@xxxxxxxxx>
---
 arch/x86/include/asm/setup.h |  2 +-
 arch/x86/kernel/head64.c     |  5 +++++
 arch/x86/kernel/setup.c      | 31 +++++++++++++++++++------------
 3 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 11af24e..7c6ca38 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -124,7 +124,7 @@ asmlinkage void __init i386_start_kernel(void);
 #else
 asmlinkage void __init x86_64_start_kernel(char *real_mode);
 asmlinkage void __init x86_64_start_reservations(char *real_mode_data);
-
+void __init setup_builtin_cmdline(void);
 #endif /* __i386__ */
 #endif /* _SETUP */
 #else
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index f129a9a..3a3f3b0 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -173,6 +173,8 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
 
 	copy_bootdata(__va(real_mode_data));
 
+	setup_builtin_cmdline();
+
 	/*
 	 * Load microcode early on BSP.
 	 */
@@ -188,7 +190,10 @@ void __init x86_64_start_reservations(char *real_mode_data)
 {
 	/* version is always not zero if it is copied */
 	if (!boot_params.hdr.version)
+	{
 		copy_bootdata(__va(real_mode_data));
+		setup_builtin_cmdline();
+	}
 
 	reserve_ebda_region();
 
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index d3d80e6..0a19059 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -832,6 +832,23 @@ dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
 	return 0;
 }
 
+
+void __init setup_builtin_cmdline(void)
+{
+#ifdef CONFIG_CMDLINE_BOOL
+#ifdef CONFIG_CMDLINE_OVERRIDE
+	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+#else
+	if (builtin_cmdline[0]) {
+		/* append boot loader cmdline to builtin */
+		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
+		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
+		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
+	}
+#endif
+#endif
+}
+
 /*
  * Determine if we were loaded by an EFI loader.  If so, then we have also been
  * passed the efi memmap, systab, etc., so we should use these data structures
@@ -955,19 +972,9 @@ void __init setup_arch(char **cmdline_p)
 	bss_resource.start = __pa_symbol(__bss_start);
 	bss_resource.end = __pa_symbol(__bss_stop)-1;
 
-#ifdef CONFIG_CMDLINE_BOOL
-#ifdef CONFIG_CMDLINE_OVERRIDE
-	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
-#else
-	if (builtin_cmdline[0]) {
-		/* append boot loader cmdline to builtin */
-		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
-		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
-		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
-	}
-#endif
+#ifdef CONFIG_X86_32
+	setup_builtin_cmdline();
 #endif
-
 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
 	*cmdline_p = command_line;
 
-- 
2.7.0.25.gfc10eb5