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linux/arch/x86_64/Makefile
Jan Beulich adf1423698 [PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
Current gcc generates calls not jumps to noreturn functions. When that happens the
return address can point to the next function, which confuses the unwinder.

This patch works around it by marking asynchronous exception
frames in contrast normal call frames in the unwind information.  Then teach
the unwinder to decode this.

For normal call frames the unwinder now subtracts one from the address which avoids
this problem.  The standard libgcc unwinder uses the same trick.

It doesn't include adjustment of the printed address (i.e. for the original
example, it'd still be kernel_math_error+0 that gets displayed, but the
unwinder wouldn't get confused anymore.

This only works with binutils 2.6.17+ and some versions of H.J.Lu's 2.6.16
unfortunately because earlier binutils don't support .cfi_signal_frame

[AK: added automatic detection of the new binutils and wrote description]

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 10:52:41 +02:00

127 lines
4.4 KiB
Makefile

#
# x86_64/Makefile
#
# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies. Remember to do have actions
# for "archclean" and "archdep" for cleaning up and making dependencies for
# this architecture
#
# This file is subject to the terms and conditions of the GNU General Public
# License. See the file "COPYING" in the main directory of this archive
# for more details.
#
# Copyright (C) 1994 by Linus Torvalds
#
# 19990713 Artur Skawina <skawina@geocities.com>
# Added '-march' and '-mpreferred-stack-boundary' support
# 20000913 Pavel Machek <pavel@suse.cz>
# Converted for x86_64 architecture
# 20010105 Andi Kleen, add IA32 compiler.
# ....and later removed it again....
#
# $Id: Makefile,v 1.31 2002/03/22 15:56:07 ak Exp $
LDFLAGS := -m elf_x86_64
OBJCOPYFLAGS := -O binary -R .note -R .comment -S
LDFLAGS_vmlinux :=
CHECKFLAGS += -D__x86_64__ -m64
cflags-y :=
cflags-kernel-y :=
cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8)
cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
cflags-y += -m64
cflags-y += -mno-red-zone
cflags-y += -mcmodel=kernel
cflags-y += -pipe
cflags-kernel-$(CONFIG_REORDER) += -ffunction-sections
# this makes reading assembly source easier, but produces worse code
# actually it makes the kernel smaller too.
cflags-y += -fno-reorder-blocks
cflags-y += -Wno-sign-compare
ifneq ($(CONFIG_UNWIND_INFO),y)
cflags-y += -fno-asynchronous-unwind-tables
endif
ifneq ($(CONFIG_DEBUG_INFO),y)
# -fweb shrinks the kernel a bit, but the difference is very small
# it also messes up debugging, so don't use it for now.
#cflags-y += $(call cc-option,-fweb)
endif
# -funit-at-a-time shrinks the kernel .text considerably
# unfortunately it makes reading oopses harder.
cflags-y += $(call cc-option,-funit-at-a-time)
# prevent gcc from generating any FP code by mistake
cflags-y += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)
# do binutils support CFI?
cflags-y += $(call as-instr,.cfi_startproc\n.cfi_endproc,-DCONFIG_AS_CFI=1,)
AFLAGS += $(call as-instr,.cfi_startproc\n.cfi_endproc,-DCONFIG_AS_CFI=1,)
# is .cfi_signal_frame supported too?
cflags-y += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
AFLAGS += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
cflags-$(CONFIG_CC_STACKPROTECTOR) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC) -fstack-protector )
cflags-$(CONFIG_CC_STACKPROTECTOR_ALL) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC) -fstack-protector-all )
CFLAGS += $(cflags-y)
CFLAGS_KERNEL += $(cflags-kernel-y)
AFLAGS += -m64
head-y := arch/x86_64/kernel/head.o arch/x86_64/kernel/head64.o arch/x86_64/kernel/init_task.o
libs-y += arch/x86_64/lib/
core-y += arch/x86_64/kernel/ \
arch/x86_64/mm/ \
arch/x86_64/crypto/
core-$(CONFIG_IA32_EMULATION) += arch/x86_64/ia32/
drivers-$(CONFIG_PCI) += arch/x86_64/pci/
drivers-$(CONFIG_OPROFILE) += arch/x86_64/oprofile/
boot := arch/x86_64/boot
PHONY += bzImage bzlilo install archmrproper \
fdimage fdimage144 fdimage288 isoimage archclean
#Default target when executing "make"
all: bzImage
BOOTIMAGE := arch/x86_64/boot/bzImage
KBUILD_IMAGE := $(BOOTIMAGE)
bzImage: vmlinux
$(Q)$(MAKE) $(build)=$(boot) $(BOOTIMAGE)
bzlilo: vmlinux
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(BOOTIMAGE) zlilo
bzdisk: vmlinux
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(BOOTIMAGE) zdisk
fdimage fdimage144 fdimage288 isoimage: vmlinux
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(BOOTIMAGE) $@
install:
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(BOOTIMAGE) $@
archclean:
$(Q)$(MAKE) $(clean)=$(boot)
define archhelp
echo '* bzImage - Compressed kernel image (arch/$(ARCH)/boot/bzImage)'
echo ' install - Install kernel using'
echo ' (your) ~/bin/installkernel or'
echo ' (distribution) /sbin/installkernel or'
echo ' install to $$(INSTALL_PATH) and run lilo'
echo ' bzdisk - Create a boot floppy in /dev/fd0'
echo ' fdimage - Create a boot floppy image'
echo ' isoimage - Create a boot CD-ROM image'
endef
CLEAN_FILES += arch/$(ARCH)/boot/fdimage \
arch/$(ARCH)/boot/image.iso \
arch/$(ARCH)/boot/mtools.conf