Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1437768 > unrolled thread

Re: [PATCHv2 2/6] x86/vdso: introduce do_map_vdso() and vdso_type enum

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  Re: [PATCHv2 2/6] x86/vdso: introduce do_map_vdso() and vdso_type enum Andy Lutomirski <luto@amacapital.net> - 2016-07-06 16:30 +0200

#1437768 — Re: [PATCHv2 2/6] x86/vdso: introduce do_map_vdso() and vdso_type enum

On Wed, Jun 29, 2016 at 3:57 AM, Dmitry Safonov <dsafonov@virtuozzo.com> wrote:
> Make in-kernel API to map vDSO blobs on x86.

I think the addr calculation was already confusing and is now even
worse.  How about simplifying it?  Get rid of calculate_addr entirely
and push the vdso_addr calls into arch_setup_additional_pages, etc.
Then just use addr directly in the map_vdso code.

> +int do_map_vdso(vdso_type type, unsigned long addr, bool randomize_addr)
>  {
> -       if (vdso32_enabled != 1)  /* Other values all mean "disabled" */
> -               return 0;
> -
> -       return map_vdso(&vdso_image_32, false);
> -}
> +       switch (type) {
> +#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
> +       case VDSO_32:
> +               if (vdso32_enabled != 1)  /* Other values all mean "disabled" */
> +                       return 0;
> +               /* vDSO aslr turned off for i386 vDSO */
> +               return map_vdso(&vdso_image_32, addr, false);
> +#endif
> +#ifdef CONFIG_X86_64
> +       case VDSO_64:
> +               if (!vdso64_enabled)
> +                       return 0;
> +               return map_vdso(&vdso_image_64, addr, randomize_addr);
> +#endif
> +#ifdef CONFIG_X86_X32_ABI
> +       case VDSO_X32:
> +               if (!vdso64_enabled)
> +                       return 0;
> +               return map_vdso(&vdso_image_x32, addr, randomize_addr);
>  #endif
> +       default:
> +               return -EINVAL;
> +       }
> +}

Why is this better than just passing the vdso_image pointer in?

[toc] | [standalone]

Back to top | Article view | linux.kernel

csiph-web