Re: [RFC][PATCH 3/4] checkpoint/restart: memory management

[Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>]

On Friday 08 August 2008, Dave Hansen wrote:
> 
> diff -puN ckpt/ckpt_hdr.h~memory_part ckpt/ckpt_hdr.h
> --- linux-2.6.git/ckpt/ckpt_hdr.h~memory_part	2008-08-05 08:37:29.000000000 -0700
> +++ linux-2.6.git-dave/ckpt/ckpt_hdr.h	2008-08-05 08:37:29.000000000 -0700
> @@ -67,3 +67,24 @@ struct cr_hdr_task {
>  };
>  
>  
> +
> +struct cr_hdr_mm {
> +	__u32 tag;	/* sharing identifier */
> +	__u64 start_code, end_code, start_data, end_data;
> +	__u64 start_brk, brk, start_stack;
> +	__u64 arg_start, arg_end, env_start, env_end;
> +	__s16 map_count;
> +};

Another structure that is not 32/64 bit ABI safe on x86. It would be safe
if you reorder the members as

struct cr_hdr_mm {
	__u32 tag;	/* sharing identifier */
	__s16 map_count;
	__u16 pad; /* not actually needed, but better to make it explicit */
	__u64 start_code, end_code, start_data, end_data;
	__u64 start_brk, brk, start_stack;
	__u64 arg_start, arg_end, env_start, env_end;
};

> +struct cr_hdr_vma {
> +	__u32 how;
> +
> +	__u64 vm_start;
> +	__u64 vm_end;
> +	__u64 vm_page_prot;
> +	__u64 vm_flags;
> +	__u64 vm_pgoff;
> +
> +	__s16 npages;
> +	__s16 namelen;
> +};

same here.


	Arnd <><