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SubjectRe: [PATCH 1/4] x86/boot/compressed/64: Compile pagetable.c unconditionally

* Kirill A. Shutemov <kirill.shutemov@linux.intel.com> wrote:

> We are going to put few helpers into pagetable.c that are not specific
> to KASLR.
>
> Let's make compilation of the file independent of KASLR and wrap
> KASLR-depended code into ifdef.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> ---
> arch/x86/boot/compressed/Makefile | 2 +-
> arch/x86/boot/compressed/pagetable.c | 5 +++++
> 2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
> index 65a150a7f15c..f7b64ecd09b3 100644
> --- a/arch/x86/boot/compressed/Makefile
> +++ b/arch/x86/boot/compressed/Makefile
> @@ -77,7 +77,7 @@ vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
> vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
> vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
> ifdef CONFIG_X86_64
> - vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/pagetable.o
> + vmlinux-objs-y += $(obj)/pagetable.o
> endif
>
> $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
> diff --git a/arch/x86/boot/compressed/pagetable.c b/arch/x86/boot/compressed/pagetable.c
> index f1aa43854bed..a15bbfcb3413 100644
> --- a/arch/x86/boot/compressed/pagetable.c
> +++ b/arch/x86/boot/compressed/pagetable.c
> @@ -27,6 +27,9 @@
> /* These actually do the work of building the kernel identity maps. */
> #include <asm/init.h>
> #include <asm/pgtable.h>
> +
> +#ifdef CONFIG_RANDOMIZE_BASE
> +
> /* Use the static base for this part of the boot process */
> #undef __PAGE_OFFSET
> #define __PAGE_OFFSET __PAGE_OFFSET_BASE
> @@ -149,3 +152,5 @@ void finalize_identity_maps(void)
> {
> write_cr3(top_level_pgt);
> }
> +
> +#endif /* CONFIG_RANDOMIZE_BASE */

The #ifdeffery becomes really ugly in this file. I think we should split these
into separate .c files:

arch/x86/boot/compressed/kaslr.c
arch/x86/boot/compressed/5-level-paging.c

With core data structures and code and a well defined interface:

arch/x86/boot/compressed/pagetable.c
arch/x86/boot/compressed/pagetable.h

or so.

Thanks,

Ingo

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