Commit 7583e8fb authored by Lukas Bulwahn's avatar Lukas Bulwahn Committed by Borislav Petkov (AMD)
Browse files

x86/cpu: Remove X86_FEATURE_NAMES 



While discussing to change the visibility of X86_FEATURE_NAMES (see Link)
in order to remove CONFIG_EMBEDDED, Boris suggested to simply make the
X86_FEATURE_NAMES functionality unconditional.

As the need for really tiny kernel images has gone away and kernel images
with !X86_FEATURE_NAMES are hardly tested, remove this config and the whole
ifdeffery in the source code.

Suggested-by: default avatarBorislav Petkov <bp@alien8.de>
Signed-off-by: default avatarLukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/all/20230509084007.24373-1-lukas.bulwahn@gmail.com/
Link: https://lore.kernel.org/r/20230510065713.10996-3-lukas.bulwahn@gmail.com
parent 424e23fd

arch/x86/Kconfig

+0 −12
Original line number Diff line number Diff line
@@ -291,7 +291,6 @@ config X86 
	select TRACE_IRQFLAGS_NMI_SUPPORT

	select USER_STACKTRACE_SUPPORT

	select HAVE_ARCH_KCSAN			if X86_64

	select X86_FEATURE_NAMES		if PROC_FS

	select PROC_PID_ARCH_STATUS		if PROC_FS

	select HAVE_ARCH_NODE_DEV_GROUP		if X86_SGX

	select FUNCTION_ALIGNMENT_16B		if X86_64 || X86_ALIGNMENT_16
@@ -441,17 +440,6 @@ config SMP 


	  If you don't know what to do here, say N.



config X86_FEATURE_NAMES

	bool

	default y

	help

	  This option compiles in a table of x86 feature bits and corresponding

	  names.  This is required to support /proc/cpuinfo and a few kernel

	  messages.  You can disable this to save space, at the expense of

	  making those few kernel messages show numeric feature bits instead.



	  If in doubt, say Y.



config X86_X2APIC

	bool "Support x2apic"

	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)

arch/x86/Kconfig.cpu

+1 −1
Original line number Diff line number Diff line
@@ -389,7 +389,7 @@ config IA32_FEAT_CTL 


config X86_VMX_FEATURE_NAMES

	def_bool y

	depends on IA32_FEAT_CTL && X86_FEATURE_NAMES

	depends on IA32_FEAT_CTL



menuconfig PROCESSOR_SELECT

	bool "Supported processor vendors" if EXPERT

arch/x86/boot/Makefile

+0 −2
Original line number Diff line number Diff line
@@ -55,14 +55,12 @@ HOST_EXTRACFLAGS += -I$(srctree)/tools/include \ 
		    -include include/generated/autoconf.h \

	            -D__EXPORTED_HEADERS__



ifdef CONFIG_X86_FEATURE_NAMES

$(obj)/cpu.o: $(obj)/cpustr.h



quiet_cmd_cpustr = CPUSTR  $@

      cmd_cpustr = $(obj)/mkcpustr > $@

$(obj)/cpustr.h: $(obj)/mkcpustr FORCE

	$(call if_changed,cpustr)

endif

targets += cpustr.h



# ---------------------------------------------------------------------------

arch/x86/boot/cpu.c

+0 −13
Original line number Diff line number Diff line
@@ -14,9 +14,7 @@ 
 */



#include "boot.h"

#ifdef CONFIG_X86_FEATURE_NAMES

#include "cpustr.h"

#endif



static char *cpu_name(int level)

{
@@ -35,7 +33,6 @@ static char *cpu_name(int level) 
static void show_cap_strs(u32 *err_flags)

{

	int i, j;

#ifdef CONFIG_X86_FEATURE_NAMES

	const unsigned char *msg_strs = (const unsigned char *)x86_cap_strs;

	for (i = 0; i < NCAPINTS; i++) {

		u32 e = err_flags[i];
@@ -58,16 +55,6 @@ static void show_cap_strs(u32 *err_flags) 
			e >>= 1;

		}

	}

#else

	for (i = 0; i < NCAPINTS; i++) {

		u32 e = err_flags[i];

		for (j = 0; j < 32; j++) {

			if (e & 1)

				printf("%d:%d ", i, j);

			e >>= 1;

		}

	}

#endif

}



int validate_cpu(void)

arch/x86/include/asm/cpufeature.h

+0 −5
Original line number Diff line number Diff line
@@ -38,15 +38,10 @@ enum cpuid_leafs 
#define X86_CAP_FMT_NUM "%d:%d"

#define x86_cap_flag_num(flag) ((flag) >> 5), ((flag) & 31)



#ifdef CONFIG_X86_FEATURE_NAMES

extern const char * const x86_cap_flags[NCAPINTS*32];

extern const char * const x86_power_flags[32];

#define X86_CAP_FMT "%s"

#define x86_cap_flag(flag) x86_cap_flags[flag]

#else

#define X86_CAP_FMT X86_CAP_FMT_NUM

#define x86_cap_flag x86_cap_flag_num

#endif



/*

 * In order to save room, we index into this array by doing