6 files changed, 71 insertions, 32 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5d0bf1aa9dcb..a11f27c4266a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -136,6 +136,7 @@ config X86
         select HAVE_ACPI_APEI if ACPI
         select HAVE_ACPI_APEI_NMI if ACPI
         select ACPI_LEGACY_TABLES_LOOKUP if ACPI
+        select X86_FEATURE_NAMES if PROC_FS
 
 config INSTRUCTION_DECODER
         def_bool y
@@ -313,6 +314,17 @@ config SMP
 
           If you don't know what to do here, say N.
 
+config X86_FEATURE_NAMES
+        bool "Processor feature human-readable names" if EMBEDDED
+        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
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index dbe8dd2fe247..5b016e2498f3 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -35,19 +35,22 @@ setup-y		+= video-vesa.o
 setup-y         += video-bios.o
 
 targets         += $(setup-y)
-hostprogs-y     := mkcpustr tools/build
+hostprogs-y     := tools/build
+hostprogs-$(CONFIG_X86_FEATURE_NAMES) += mkcpustr
 
 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 > $@
-targets         += cpustr.h
+targets += cpustr.h
 $(obj)/cpustr.h: $(obj)/mkcpustr FORCE
         $(call if_changed,cpustr)
+endif
 
 # ---------------------------------------------------------------------------
 
diff --git a/arch/x86/boot/cpu.c b/arch/x86/boot/cpu.c
index 6ec6bb6e9957..29207f69ae8c 100644
--- a/arch/x86/boot/cpu.c
+++ b/arch/x86/boot/cpu.c
@@ -16,7 +16,9 @@
  */
 
 #include "boot.h"
+#ifdef CONFIG_X86_FEATURE_NAMES
 #include "cpustr.h"
+#endif
 
 static char *cpu_name(int level)
 {
@@ -32,11 +34,48 @@ 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];
+                for (j = 0; j < 32; j++) {
+                        if (msg_strs[0] < i ||
+                            (msg_strs[0] == i && msg_strs[1] < j)) {
+                                /* Skip to the next string */
+                                msg_strs += 2;
+                                while (*msg_strs++)
+                                        ;
+                        }
+                        if (e & 1) {
+                                if (msg_strs[0] == i &&
+                                    msg_strs[1] == j &&
+                                    msg_strs[2])
+                                        printf("%s ", msg_strs+2);
+                                else
+                                        printf("%d:%d ", i, j);
+                        }
+                        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)
 {
         u32 *err_flags;
         int cpu_level, req_level;
-        const unsigned char *msg_strs;
 
         check_cpu(&cpu_level, &req_level, &err_flags);
 
@@ -49,34 +88,9 @@ int validate_cpu(void)
         }
 
         if (err_flags) {
-                int i, j;
                 puts("This kernel requires the following features "
                      "not present on the CPU:\n");
-
-                msg_strs = (const unsigned char *)x86_cap_strs;
-
-                for (i = 0; i < NCAPINTS; i++) {
-                        u32 e = err_flags[i];
-
-                        for (j = 0; j < 32; j++) {
-                                if (msg_strs[0] < i ||
-                                    (msg_strs[0] == i && msg_strs[1] < j)) {
-                                        /* Skip to the next string */
-                                        msg_strs += 2;
-                                        while (*msg_strs++)
-                                                ;
-                                }
-                                if (e & 1) {
-                                        if (msg_strs[0] == i &&
-                                            msg_strs[1] == j &&
-                                            msg_strs[2])
-                                                printf("%s ", msg_strs+2);
-                                        else
-                                                printf("%d:%d ", i, j);
-                                }
-                                e >>= 1;
-                        }
-                }
+                show_cap_strs(err_flags);
                 putchar('\n');
                 return -1;
         } else {
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index bb9b258d60e7..516903b98e06 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -250,8 +250,15 @@
 #include <asm/asm.h>
 #include <linux/bitops.h>
 
+#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 "%d:%d"
+#define x86_cap_flag(flag) ((flag) >> 5), ((flag) & 31)
+#endif
 
 /*
  * In order to save room, we index into this array by doing
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 64038d842c57..77dcab277710 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -13,11 +13,12 @@ nostackp := $(call cc-option, -fno-stack-protector)
 CFLAGS_common.o         := $(nostackp)
 
 obj-y                   := intel_cacheinfo.o scattered.o topology.o
-obj-y                   += capflags.o powerflags.o common.o
+obj-y                   += common.o
 obj-y                   += rdrand.o
 obj-y                   += match.o
 
 obj-$(CONFIG_PROC_FS)   += proc.o
+obj-$(CONFIG_X86_FEATURE_NAMES) += capflags.o powerflags.o
 
 obj-$(CONFIG_X86_32)    += bugs.o
 obj-$(CONFIG_X86_64)    += bugs_64.o
@@ -50,6 +51,7 @@ obj-$(CONFIG_X86_LOCAL_APIC)		+= perfctr-watchdog.o perf_event_amd_ibs.o
 
 obj-$(CONFIG_HYPERVISOR_GUEST)          += vmware.o hypervisor.o mshyperv.o
 
+ifdef CONFIG_X86_FEATURE_NAMES
 quiet_cmd_mkcapflags = MKCAP   $@
       cmd_mkcapflags = $(CONFIG_SHELL) $(srctree)/$(src)/mkcapflags.sh $< $@
 
@@ -58,3 +60,4 @@ cpufeature = $(src)/../../include/asm/cpufeature.h
 targets += capflags.c
 $(obj)/capflags.c: $(cpufeature) $(src)/mkcapflags.sh FORCE
         $(call if_changed,mkcapflags)
+endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index e4ab2b42bd6f..c649f236e288 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -346,8 +346,8 @@ static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
                         continue;
 
                 printk(KERN_WARNING
-                       "CPU: CPU feature %s disabled, no CPUID level 0x%x\n",
-                                x86_cap_flags[df->feature], df->level);
+                       "CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n",
+                                x86_cap_flag(df->feature), df->level);
         }
 }