On Tue, Aug 12, 2008 at 11:14:28AM +0800, Huang Ying wrote:
> Kexec/Kexec-jump require code size in control page is less than
> PAGE_SIZE/2. This patch add link-time checking for this.
>
> ASSERT() of ld link script is used as the link-time checking
> mechanism.
>
> Signed-off-by: Huang Ying <[EMAIL PROTECTED]>
>
> ---
> arch/x86/kernel/machine_kexec_32.c |2 +-
> arch/x86/kernel/relocate_kernel_32.S | 10 +++---
> arch/x86/kernel/vmlinux_32.lds.S |6 ++
> include/asm-x86/kexec.h |4
> 4 files changed, 18 insertions(+), 4 deletions(-)
>
> --- a/arch/x86/kernel/machine_kexec_32.c
> +++ b/arch/x86/kernel/machine_kexec_32.c
> @@ -138,7 +138,7 @@ void machine_kexec(struct kimage *image)
> }
>
> control_page = page_address(image->control_code_page);
> - memcpy(control_page, relocate_kernel, PAGE_SIZE/2);
> + memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
>
> relocate_kernel_ptr = control_page;
> page_list[PA_CONTROL_PAGE] = __pa(control_page);
> --- a/arch/x86/kernel/relocate_kernel_32.S
> +++ b/arch/x86/kernel/relocate_kernel_32.S
> @@ -20,10 +20,11 @@
> #define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
> #define PAE_PGD_ATTR (_PAGE_PRESENT)
>
> -/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
> - * used to save some data for jumping back
> +/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
> + * ~ control_page + PAGE_SIZE are used as data storage and stack for
> + * jumping back
> */
> -#define DATA(offset) (PAGE_SIZE/2+(offset))
> +#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
>
> /* Minimal CPU state */
> #define ESP DATA(0x0)
> @@ -376,3 +377,6 @@ swap_pages:
> popl%ebx
> popl%ebp
> ret
> +
> + .globl kexec_control_code_size
> +.set kexec_control_code_size, . - relocate_kernel
> --- a/include/asm-x86/kexec.h
> +++ b/include/asm-x86/kexec.h
> @@ -41,6 +41,10 @@
> # define PAGES_NR17
> #endif
>
> +#ifdef CONFIG_X86_32
> +# define KEXEC_CONTROL_CODE_MAX_SIZE 2048
> +#endif
> +
> #ifndef __ASSEMBLY__
>
> #include
> --- a/arch/x86/kernel/vmlinux_32.lds.S
> +++ b/arch/x86/kernel/vmlinux_32.lds.S
> @@ -209,3 +209,9 @@ SECTIONS
>
>DWARF_DEBUG
> }
> +
> +/* Link time checks */
> +#include
> +
> +ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
> + "kexec control code size is too big")
Hi Huang,
Will above ASSERT() still compile if CONFIG_KEXEC=n? If yes, then it
looks good to me.
Acked-by: Vivek Goyal <[EMAIL PROTECTED]>
Thanks
Vivek
___
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
