diff options
| author | Vivek Goyal <vgoyal@in.ibm.com> | 2007-05-02 19:27:07 +0200 |
|---|---|---|
| committer | Andi Kleen <andi@basil.nowhere.org> | 2007-05-02 19:27:07 +0200 |
| commit | 1ab60e0f72f71ec54831e525a3e1154f1c092408 (patch) | |
| tree | bd7dd8bbff43e3e2e3597f2b7780e82a856bb9d7 /arch/x86_64/boot/compressed/Makefile | |
| parent | 0dbf7028c0c1f266c9631139450a1502d3cd457e (diff) | |
[PATCH] x86-64: Relocatable Kernel Support
This patch modifies the x86_64 kernel so that it can be loaded and run
at any 2M aligned address, below 512G. The technique used is to
compile the decompressor with -fPIC and modify it so the decompressor
is fully relocatable. For the main kernel the page tables are
modified so the kernel remains at the same virtual address. In
addition a variable phys_base is kept that holds the physical address
the kernel is loaded at. __pa_symbol is modified to add that when
we take the address of a kernel symbol.
When loaded with a normal bootloader the decompressor will decompress
the kernel to 2M and it will run there. This both ensures the
relocation code is always working, and makes it easier to use 2M
pages for the kernel and the cpu.
AK: changed to not make RELOCATABLE default in Kconfig
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'arch/x86_64/boot/compressed/Makefile')
| -rw-r--r-- | arch/x86_64/boot/compressed/Makefile | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/arch/x86_64/boot/compressed/Makefile b/arch/x86_64/boot/compressed/Makefile index e70fa6e1da0..705a3e33d7e 100644 --- a/arch/x86_64/boot/compressed/Makefile +++ b/arch/x86_64/boot/compressed/Makefile @@ -8,16 +8,14 @@ targets := vmlinux vmlinux.bin vmlinux.bin.gz head.o misc.o piggy.o EXTRA_AFLAGS := -traditional -AFLAGS := $(subst -m64,-m32,$(AFLAGS)) # cannot use EXTRA_CFLAGS because base CFLAGS contains -mkernel which conflicts with # -m32 -CFLAGS := -m32 -D__KERNEL__ -Iinclude -O2 -fno-strict-aliasing -LDFLAGS := -m elf_i386 +CFLAGS := -m64 -D__KERNEL__ -Iinclude -O2 -fno-strict-aliasing -fPIC -mcmodel=small -fno-builtin +LDFLAGS := -m elf_x86_64 -LDFLAGS_vmlinux := -Ttext $(IMAGE_OFFSET) -e startup_32 -m elf_i386 - -$(obj)/vmlinux: $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o FORCE +LDFLAGS_vmlinux := -T +$(obj)/vmlinux: $(src)/vmlinux.lds $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o FORCE $(call if_changed,ld) @: @@ -27,7 +25,7 @@ $(obj)/vmlinux.bin: vmlinux FORCE $(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE $(call if_changed,gzip) -LDFLAGS_piggy.o := -r --format binary --oformat elf32-i386 -T +LDFLAGS_piggy.o := -r --format binary --oformat elf64-x86-64 -T $(obj)/piggy.o: $(obj)/vmlinux.scr $(obj)/vmlinux.bin.gz FORCE $(call if_changed,ld) |