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linux/arch/um/Makefile
Richard Weinberger 12783aa077 um: Switch to large mcmodel on x86_64
x86_64 UML is unable to load modules if more than 504MiB
of memory are used.
This happens because on x86_64 the UML process has a quite high
start address (typically around 0x6000000).
If UML's memory is larger than 504MiB VMALLOC_START happens to be after
0x8000000. This is no problem unless one loads a module which was built
with R_X86_64_32S relocations.
Symbols with a location > 0x8000000 cannot be used with R_X86_64_32S

To deal with this x86_64 UML has to be compiled with -mcmodel=large
such that no R_X86_64_32S relocations are used.

Signed-off-by: Richard Weinberger <richard@nod.at>
Reported-by: 전하늘 <allskyee@gmail.com>
2012-03-25 00:29:57 +01:00

164 lines
4.9 KiB
Makefile

#
# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies.
#
# Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
# Licensed under the GPL
#
ARCH_DIR := arch/um
OS := $(shell uname -s)
# We require bash because the vmlinux link and loader script cpp use bash
# features.
SHELL := /bin/bash
filechk_gen_header = $<
core-y += $(ARCH_DIR)/kernel/ \
$(ARCH_DIR)/drivers/ \
$(ARCH_DIR)/os-$(OS)/
MODE_INCLUDE += -I$(srctree)/$(ARCH_DIR)/include/shared/skas
HEADER_ARCH := $(SUBARCH)
# Additional ARCH settings for x86
ifeq ($(SUBARCH),i386)
HEADER_ARCH := x86
endif
ifeq ($(SUBARCH),x86_64)
HEADER_ARCH := x86
KBUILD_CFLAGS += -mcmodel=large
endif
HOST_DIR := arch/$(HEADER_ARCH)
include $(srctree)/$(ARCH_DIR)/Makefile-skas
include $(srctree)/$(HOST_DIR)/Makefile.um
core-y += $(HOST_DIR)/um/
SHARED_HEADERS := $(ARCH_DIR)/include/shared
ARCH_INCLUDE := -I$(srctree)/$(SHARED_HEADERS)
ARCH_INCLUDE += -I$(srctree)/$(HOST_DIR)/um/shared
KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/um
# -Dvmap=kernel_vmap prevents anything from referencing the libpcap.o symbol so
# named - it's a common symbol in libpcap, so we get a binary which crashes.
#
# Same things for in6addr_loopback and mktime - found in libc. For these two we
# only get link-time error, luckily.
#
# These apply to USER_CFLAGS to.
KBUILD_CFLAGS += $(CFLAGS) $(CFLAGS-y) -D__arch_um__ \
$(ARCH_INCLUDE) $(MODE_INCLUDE) -Dvmap=kernel_vmap \
-Din6addr_loopback=kernel_in6addr_loopback \
-Din6addr_any=kernel_in6addr_any -Dstrrchr=kernel_strrchr
KBUILD_AFLAGS += $(ARCH_INCLUDE)
USER_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -D__KERNEL__,,\
$(patsubst -I%,,$(KBUILD_CFLAGS)))) $(ARCH_INCLUDE) $(MODE_INCLUDE) \
$(filter -I%,$(CFLAGS)) -D_FILE_OFFSET_BITS=64 -idirafter include
#This will adjust *FLAGS accordingly to the platform.
include $(srctree)/$(ARCH_DIR)/Makefile-os-$(OS)
KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
-I$(HOST_DIR)/include/generated
# -Derrno=kernel_errno - This turns all kernel references to errno into
# kernel_errno to separate them from the libc errno. This allows -fno-common
# in KBUILD_CFLAGS. Otherwise, it would cause ld to complain about the two different
# errnos.
# These apply to kernelspace only.
#
# strip leading and trailing whitespace to make the USER_CFLAGS removal of these
# defines more robust
KERNEL_DEFINES = $(strip -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask \
-Dmktime=kernel_mktime $(ARCH_KERNEL_DEFINES))
KBUILD_CFLAGS += $(KERNEL_DEFINES)
PHONY += linux
all: linux
linux: vmlinux
@echo ' LINK $@'
$(Q)ln -f $< $@
define archhelp
echo '* linux - Binary kernel image (./linux) - for backward'
echo ' compatibility only, this creates a hard link to the'
echo ' real kernel binary, the "vmlinux" binary you'
echo ' find in the kernel root.'
endef
KBUILD_KCONFIG := $(HOST_DIR)/um/Kconfig
archheaders:
$(Q)$(MAKE) -C '$(srctree)' KBUILD_SRC= \
ARCH=$(HEADER_ARCH) O='$(objtree)' archheaders
archprepare: include/generated/user_constants.h
LINK-$(CONFIG_LD_SCRIPT_STATIC) += -static
LINK-$(CONFIG_LD_SCRIPT_DYN) += -Wl,-rpath,/lib
CFLAGS_NO_HARDENING := $(call cc-option, -fno-PIC,) $(call cc-option, -fno-pic,) \
$(call cc-option, -fno-stack-protector,) \
$(call cc-option, -fno-stack-protector-all,)
# Options used by linker script
export LDS_START := $(START)
export LDS_ELF_ARCH := $(ELF_ARCH)
export LDS_ELF_FORMAT := $(ELF_FORMAT)
# The wrappers will select whether using "malloc" or the kernel allocator.
LINK_WRAPS = -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc
LD_FLAGS_CMDLINE = $(foreach opt,$(LDFLAGS),-Wl,$(opt))
CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)
define cmd_vmlinux__
$(CC) $(CFLAGS_vmlinux) -o $@ \
-Wl,-T,$(vmlinux-lds) $(vmlinux-init) \
-Wl,--start-group $(vmlinux-main) -Wl,--end-group \
-lutil \
$(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o \
FORCE ,$^) ; rm -f linux
endef
# When cleaning we don't include .config, so we don't include
# TT or skas makefiles and don't clean skas_ptregs.h.
CLEAN_FILES += linux x.i gmon.out
archclean:
@find . \( -name '*.bb' -o -name '*.bbg' -o -name '*.da' \
-o -name '*.gcov' \) -type f -print | xargs rm -f
# Generated files
$(HOST_DIR)/um/user-offsets.s: __headers FORCE
$(Q)$(MAKE) $(build)=$(HOST_DIR)/um $@
define filechk_gen-asm-offsets
(set -e; \
echo "/*"; \
echo " * DO NOT MODIFY."; \
echo " *"; \
echo " * This file was generated by arch/$(ARCH)/Makefile"; \
echo " *"; \
echo " */"; \
echo ""; \
sed -ne "/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}"; \
echo ""; )
endef
include/generated/user_constants.h: $(HOST_DIR)/um/user-offsets.s
$(call filechk,gen-asm-offsets)
export SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING OS DEV_NULL_PATH