Commit 20d00213 authored by Paolo 'Blaisorblade' Giarrusso's avatar Paolo 'Blaisorblade' Giarrusso Committed by Linus Torvalds
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[PATCH] uml: allow building as 32-bit binary on 64bit host 



This patch makes the command:

make ARCH=um SUBARCH=i386

work on x86_64 hosts (with support for building 32-bit binaries).  This is
especially needed since 64-bit UMLs don't support 32-bit emulation for guest
binaries, currently.  This has been tested in all possible cases and works.

Only exception is that I've built but not tested a 64-bit binary, because I
hadn't a 64-bit filesystem available.

Signed-off-by: default avatarPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent ecc354a9

arch/um/Makefile

+4 −7
Original line number Diff line number Diff line
@@ -51,11 +51,6 @@ MRPROPER_DIRS += $(ARCH_DIR)/include2 
endif

SYS_DIR		:= $(ARCH_DIR)/include/sysdep-$(SUBARCH)



include $(srctree)/$(ARCH_DIR)/Makefile-$(SUBARCH)



core-y += $(SUBARCH_CORE)

libs-y += $(SUBARCH_LIBS)



# -Dvmap=kernel_vmap affects everything, and prevents anything from

# referencing the libpcap.o symbol so named.
@@ -64,7 +59,7 @@ CFLAGS += $(CFLAGS-y) -D__arch_um__ -DSUBARCH=\"$(SUBARCH)\" \ 


USER_CFLAGS := $(patsubst -I%,,$(CFLAGS))

USER_CFLAGS := $(patsubst -D__KERNEL__,,$(USER_CFLAGS)) $(ARCH_INCLUDE) \

	$(MODE_INCLUDE) $(ARCH_USER_CFLAGS)

	$(MODE_INCLUDE)



# -Derrno=kernel_errno - This turns all kernel references to errno into

# kernel_errno to separate them from the libc errno.  This allows -fno-common
@@ -74,6 +69,8 @@ USER_CFLAGS := $(patsubst -D__KERNEL__,,$(USER_CFLAGS)) $(ARCH_INCLUDE) \ 
CFLAGS += -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask

CFLAGS += $(call cc-option,-fno-unit-at-a-time,)



include $(srctree)/$(ARCH_DIR)/Makefile-$(SUBARCH)



#This will adjust *FLAGS accordingly to the platform.

include $(srctree)/$(ARCH_DIR)/Makefile-os-$(OS)
@@ -132,7 +129,7 @@ CPPFLAGS_vmlinux.lds = -U$(SUBARCH) \ 
#The wrappers will select whether using "malloc" or the kernel allocator.

LINK_WRAPS = -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc



CFLAGS_vmlinux = $(LINK-y) $(LINK_WRAPS)

CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS)

define cmd_vmlinux__

	$(CC) $(CFLAGS_vmlinux) -o $@ \

	-Wl,-T,$(vmlinux-lds) $(vmlinux-init) \

arch/um/Makefile-i386

+21 −10
Original line number Diff line number Diff line 
SUBARCH_CORE := arch/um/sys-i386/ arch/i386/crypto/

core-y += arch/um/sys-i386/ arch/i386/crypto/



TOP_ADDR := $(CONFIG_TOP_ADDR)
@@ -8,20 +8,31 @@ ifeq ($(CONFIG_MODE_SKAS),y) 
  endif

endif



LDFLAGS			+= -m elf_i386

ELF_ARCH		:= $(SUBARCH)

ELF_FORMAT 		:= elf32-$(SUBARCH)

OBJCOPYFLAGS  		:= -O binary -R .note -R .comment -S



ifeq ("$(origin SUBARCH)", "command line")

ifneq ("$(shell uname -m | sed -e s/i.86/i386/)", "$(SUBARCH)")

CFLAGS			+= $(call cc-option,-m32)

USER_CFLAGS		+= $(call cc-option,-m32)

HOSTCFLAGS		+= $(call cc-option,-m32)

HOSTLDFLAGS		+= $(call cc-option,-m32)

AFLAGS			+= $(call cc-option,-m32)

LINK-y			+= $(call cc-option,-m32)

UML_OBJCOPYFLAGS	+= -F $(ELF_FORMAT)



export LDFLAGS HOSTCFLAGS HOSTLDFLAGS UML_OBJCOPYFLAGS

endif

endif



CFLAGS += -U__$(SUBARCH)__ -U$(SUBARCH) $(STUB_CFLAGS)

ARCH_USER_CFLAGS :=



ifneq ($(CONFIG_GPROF),y)

ARCH_CFLAGS += -DUM_FASTCALL

endif



ELF_ARCH := $(SUBARCH)

ELF_FORMAT := elf32-$(SUBARCH)



OBJCOPYFLAGS  := -O binary -R .note -R .comment -S



SYS_UTIL_DIR	:= $(ARCH_DIR)/sys-i386/util



SYS_HEADERS	:= $(SYS_DIR)/sc.h $(SYS_DIR)/thread.h



prepare: $(SYS_HEADERS)

arch/um/Makefile-x86_64

+4 −2
Original line number Diff line number Diff line 
# Copyright 2003 - 2004 Pathscale, Inc

# Released under the GPL



SUBARCH_LIBS := arch/um/sys-x86_64/

libs-y += arch/um/sys-x86_64/

START := 0x60000000



#We #undef __x86_64__ for kernelspace, not for userspace where

#it's needed for headers to work!

CFLAGS += -U__$(SUBARCH)__ -fno-builtin $(STUB_CFLAGS)

ARCH_USER_CFLAGS := -D__x86_64__

USER_CFLAGS += -fno-builtin



ELF_ARCH := i386:x86-64

ELF_FORMAT := elf64-x86-64

arch/um/scripts/Makefile.unmap

+2 −2
Original line number Diff line number Diff line
@@ -12,8 +12,8 @@ $(obj)/unmap.o: _c_flags = $(call unprofile,$(CFLAGS)) 


quiet_cmd_wrapld = LD      $@

define cmd_wrapld

	$(LD) -r -o $(obj)/unmap_tmp.o $< $(shell $(CC) -print-file-name=libc.a); \

	$(OBJCOPY) $(obj)/unmap_tmp.o $@ -G switcheroo

	$(LD) $(LDFLAGS) -r -o $(obj)/unmap_tmp.o $< $(shell $(CC) $(CFLAGS) -print-file-name=libc.a); \

	$(OBJCOPY) $(UML_OBJCOPYFLAGS) $(obj)/unmap_tmp.o $@ -G switcheroo

endef



$(obj)/unmap_fin.o : $(obj)/unmap.o FORCE

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