Commit e6bcfdd7 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Borislav Petkov (AMD)
Browse files

x86/microcode: Hide the config knob 



In reality CONFIG_MICROCODE is enabled in any reasonable configuration when
Intel or AMD support is enabled. Accommodate to reality.

Suggested-by: default avatarBorislav Petkov <bp@alien8.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230812195727.660453052@linutronix.de
parent e5a81929

arch/x86/Kconfig

+1 −37
Original line number Diff line number Diff line
@@ -1308,44 +1308,8 @@ config X86_REBOOTFIXUPS 
	  Say N otherwise.



config MICROCODE

	bool "CPU microcode loading support"

	default y

	def_bool y

	depends on CPU_SUP_AMD || CPU_SUP_INTEL

	help

	  If you say Y here, you will be able to update the microcode on

	  Intel and AMD processors. The Intel support is for the IA32 family,

	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The

	  AMD support is for families 0x10 and later. You will obviously need

	  the actual microcode binary data itself which is not shipped with

	  the Linux kernel.



	  The preferred method to load microcode from a detached initrd is described

	  in Documentation/arch/x86/microcode.rst. For that you need to enable

	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the

	  initrd for microcode blobs.



	  In addition, you can build the microcode into the kernel. For that you

	  need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE

	  config option.



config MICROCODE_INTEL

	bool "Intel microcode loading support"

	depends on CPU_SUP_INTEL && MICROCODE

	default MICROCODE

	help

	  This options enables microcode patch loading support for Intel

	  processors.



	  For the current Intel microcode data package go to

	  <https://downloadcenter.intel.com> and search for

	  'Linux Processor Microcode Data File'.



config MICROCODE_AMD

	bool "AMD microcode loading support"

	depends on CPU_SUP_AMD && MICROCODE

	help

	  If you select this option, microcode patch loading support for AMD

	  processors will be enabled.



config MICROCODE_LATE_LOADING

	bool "Late microcode loading (DANGEROUS)"

arch/x86/include/asm/microcode.h

+3 −3
Original line number Diff line number Diff line
@@ -54,16 +54,16 @@ struct ucode_cpu_info { 
extern struct ucode_cpu_info ucode_cpu_info[];

struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa);



#ifdef CONFIG_MICROCODE_INTEL

#ifdef CONFIG_CPU_SUP_INTEL

extern struct microcode_ops * __init init_intel_microcode(void);

#else

static inline struct microcode_ops * __init init_intel_microcode(void)

{

	return NULL;

}

#endif /* CONFIG_MICROCODE_INTEL */

#endif /* CONFIG_CPU_SUP_INTEL */



#ifdef CONFIG_MICROCODE_AMD

#ifdef CONFIG_CPU_SUP_AMD

extern struct microcode_ops * __init init_amd_microcode(void);

extern void __exit exit_amd_microcode(void);

#else

arch/x86/include/asm/microcode_amd.h

+1 −1
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ struct microcode_amd { 


#define PATCH_MAX_SIZE (3 * PAGE_SIZE)



#ifdef CONFIG_MICROCODE_AMD

#ifdef CONFIG_CPU_SUP_AMD

extern void load_ucode_amd_early(unsigned int cpuid_1_eax);

extern int __init save_microcode_in_initrd_amd(unsigned int family);

void reload_ucode_amd(unsigned int cpu);

arch/x86/include/asm/microcode_intel.h

+1 −1
Original line number Diff line number Diff line
@@ -71,7 +71,7 @@ static inline u32 intel_get_microcode_revision(void) 
	return rev;

}



#ifdef CONFIG_MICROCODE_INTEL

#ifdef CONFIG_CPU_SUP_INTEL

extern void __init load_ucode_intel_bsp(void);

extern void load_ucode_intel_ap(void);

extern void show_ucode_info_early(void);

arch/x86/kernel/cpu/microcode/Makefile

+2 −2
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0-only

microcode-y				:= core.o

obj-$(CONFIG_MICROCODE)			+= microcode.o

microcode-$(CONFIG_MICROCODE_INTEL)	+= intel.o

microcode-$(CONFIG_MICROCODE_AMD)	+= amd.o
 
microcode-$(CONFIG_CPU_SUP_INTEL)	+= intel.o

microcode-$(CONFIG_CPU_SUP_AMD)		+= amd.o