Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 build updates from Ingo Molnar:
 "The biggest change is the forcing of asm-goto support on x86, which
  effectively increases the GCC minimum supported version to gcc-4.5 (on
  x86)"

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build: Don't pass in -D__KERNEL__ multiple times
  x86: Remove FAST_FEATURE_TESTS
  x86: Force asm-goto
  x86/build: Drop superfluous ALIGN from the linker script

Makefile

@@ -496,6 +496,13 @@ RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
 RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
 export RETPOLINE_CFLAGS
 
+# check for 'asm goto'
+ifeq ($(call shell-cached,$(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
+  CC_HAVE_ASM_GOTO := 1
+  KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
+  KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
+endif
+
 ifeq ($(config-targets),1)
 # ===========================================================================
 # *config targets only - make sure prerequisites are updated, and descend
@@ -660,12 +667,6 @@ KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \
 # Tell gcc to never replace conditional load with a non-conditional one
 KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
 
-# check for 'asm goto'
-ifeq ($(call shell-cached,$(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
-	KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
-	KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
-endif
-
 include scripts/Makefile.kcov
 include scripts/Makefile.gcc-plugins
 

arch/x86/Kconfig

@@ -393,17 +393,6 @@ config X86_FEATURE_NAMES
 
 	  If in doubt, say Y.
 
-config X86_FAST_FEATURE_TESTS
-	bool "Fast CPU feature tests" if EMBEDDED
-	default y
-	---help---
-	  Some fast-paths in the kernel depend on the capabilities of the CPU.
-	  Say Y here for the kernel to patch in the appropriate code at runtime
-	  based on the capabilities of the CPU. The infrastructure for patching
-	  code at runtime takes up some additional space; space-constrained
-	  embedded systems may wish to say N here to produce smaller, slightly
-	  slower code.
-
 config X86_X2APIC
 	bool "Support x2apic"
 	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)

arch/x86/Makefile

@@ -31,8 +31,7 @@ endif
 CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
 M16_CFLAGS	 := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
 
-REALMODE_CFLAGS	:= $(M16_CFLAGS) -g -Os -D__KERNEL__ \
+REALMODE_CFLAGS	:= $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \
-		   -DDISABLE_BRANCH_PROFILING \
 		   -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
 		   -fno-strict-aliasing -fomit-frame-pointer -fno-pic \
 		   -mno-mmx -mno-sse
@@ -181,6 +180,10 @@ ifdef CONFIG_FUNCTION_GRAPH_TRACER
   endif
 endif
 
+ifndef CC_HAVE_ASM_GOTO
+  $(error Compiler lacks asm-goto support.)
+endif
+
 #
 # Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a
 # GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226).  There's no way

arch/x86/boot/compressed/Makefile

@@ -26,7 +26,7 @@ KCOV_INSTRUMENT		:= n
 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
 	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
 
-KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ -O2
+KBUILD_CFLAGS := -m$(BITS) -O2
 KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
 KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
 cflags-$(CONFIG_X86_32) := -march=i386

arch/x86/include/asm/cpufeature.h

@@ -140,7 +140,6 @@ extern void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int bit);
 
 #define setup_force_cpu_bug(bit) setup_force_cpu_cap(bit)
 
-#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_X86_FAST_FEATURE_TESTS)
 /*
  * Static testing of CPU features.  Used the same as boot_cpu_has().
  * These will statically patch the target code for additional
@@ -196,13 +195,6 @@ static __always_inline __pure bool _static_cpu_has(u16 bit)
 		boot_cpu_has(bit) :				\
 		_static_cpu_has(bit)				\
 )
-#else
-/*
- * Fall back to dynamic for gcc versions which don't support asm goto. Should be
- * a minority now anyway.
- */
-#define static_cpu_has(bit)		boot_cpu_has(bit)
-#endif
 
 #define cpu_has_bug(c, bit)		cpu_has(c, (bit))
 #define set_cpu_bug(c, bit)		set_cpu_cap(c, (bit))

arch/x86/kernel/vmlinux.lds.S

@@ -102,7 +102,6 @@ SECTIONS
 		_stext = .;
 		/* bootstrapping code */
 		HEAD_TEXT
-		. = ALIGN(8);
 		TEXT_TEXT
 		SCHED_TEXT
 		CPUIDLE_TEXT
@@ -200,7 +199,7 @@ SECTIONS
 		. = __vvar_beginning_hack + PAGE_SIZE;
 	} :data
 
-       . = ALIGN(__vvar_page + PAGE_SIZE, PAGE_SIZE);
+	. = ALIGN(__vvar_page + PAGE_SIZE, PAGE_SIZE);
 
 	/* Init code and data - will be freed after init */
 	. = ALIGN(PAGE_SIZE);
@@ -368,8 +367,8 @@ SECTIONS
 	. = ALIGN(PAGE_SIZE);		/* keep VO_INIT_SIZE page aligned */
 	_end = .;
 
-        STABS_DEBUG
+	STABS_DEBUG
-        DWARF_DEBUG
+	DWARF_DEBUG
 
 	/* Sections to be discarded */
 	DISCARDS