This is the mail archive of the libc-alpha@sourceware.org mailing list for the glibc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] ld.so: Add architecture specific fields


On Tue, Oct 31, 2017 at 9:37 AM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> To support Intel Control-flow Enforcement Technology (CET) run-time
> control:
>
> 1. An architecture specific field in the writable ld.so namespace is
> needed to indicate if CET features are enabled at run-time.
> 2. An architecture specific field in struct link_map is needed if
> CET features are enabled in an ELF module.
>
> This patch adds dl-procruntime.c to the writable ld.so namespace and
> link_map.h to struct link_map.
>
> Tested on x86-64.
>
> Any comments?
>
> H.J.
> --
>         * elf/dl-support.c: Include <dl-procruntime.c>.
>         * include/link.h: Include <link_map.h>.
>         * sysdeps/generic/dl-procruntime.c: New file.
>         * sysdeps/generic/link_map.h: Likewise.
>         * sysdeps/generic/ldsodefs.h: Include <dl-procruntime.c> in
>         the writable ld.so namespace.
> ---
>  elf/dl-support.c                 |  1 +
>  include/link.h                   |  2 ++
>  sysdeps/generic/dl-procruntime.c |  1 +
>  sysdeps/generic/ldsodefs.h       | 11 +++++++----
>  sysdeps/generic/link_map.h       |  1 +
>  5 files changed, 12 insertions(+), 4 deletions(-)
>  create mode 100644 sysdeps/generic/dl-procruntime.c
>  create mode 100644 sysdeps/generic/link_map.h
>
> diff --git a/elf/dl-support.c b/elf/dl-support.c
> index 5e3de90598..235d3a7f46 100644
> --- a/elf/dl-support.c
> +++ b/elf/dl-support.c
> @@ -126,6 +126,7 @@ int _dl_starting_up = 1;
>  void *_dl_random;
>
>  /* Get architecture specific initializer.  */
> +#include <dl-procruntime.c>
>  #include <dl-procinfo.c>
>
>  /* Initial value of the CPU clock.  */
> diff --git a/include/link.h b/include/link.h
> index 3e1b2aefb7..82b77a6b41 100644
> --- a/include/link.h
> +++ b/include/link.h
> @@ -203,6 +203,8 @@ struct link_map
>                                        freed, ie. not allocated with
>                                        the dummy malloc in ld.so.  */
>
> +#include <link_map.h>
> +
>      /* Collected information about own RPATH directories.  */
>      struct r_search_path_struct l_rpath_dirs;
>
> diff --git a/sysdeps/generic/dl-procruntime.c b/sysdeps/generic/dl-procruntime.c
> new file mode 100644
> index 0000000000..a056184690
> --- /dev/null
> +++ b/sysdeps/generic/dl-procruntime.c
> @@ -0,0 +1 @@
> +/* No architecture specific definitions.  */
> diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
> index 5efae2d96d..52a792a597 100644
> --- a/sysdeps/generic/ldsodefs.h
> +++ b/sysdeps/generic/ldsodefs.h
> @@ -373,6 +373,13 @@ struct rtld_global
>    EXTERN void (*_dl_rtld_unlock_recursive) (void *);
>  #endif
>
> +  /* Get architecture specific definitions.  */
> +#define PROCINFO_DECL
> +#ifndef PROCINFO_CLASS
> +# define PROCINFO_CLASS EXTERN
> +#endif
> +#include <dl-procruntime.c>
> +
>    /* If loading a shared object requires that we make the stack executable
>       when it was not, we do it by calling this function.
>       It returns an errno code or zero on success.  */
> @@ -529,10 +536,6 @@ struct rtld_global_ro
>  #endif
>
>    /* Get architecture specific definitions.  */
> -#define PROCINFO_DECL
> -#ifndef PROCINFO_CLASS
> -# define PROCINFO_CLASS EXTERN
> -#endif
>  #include <dl-procinfo.c>
>
>    /* Names of shared object for which the RPATH should be ignored.  */
> diff --git a/sysdeps/generic/link_map.h b/sysdeps/generic/link_map.h
> new file mode 100644
> index 0000000000..a056184690
> --- /dev/null
> +++ b/sysdeps/generic/link_map.h
> @@ -0,0 +1 @@
> +/* No architecture specific definitions.  */
> --
> 2.13.6
>

I tested it with build-many-glibcs.py.  If there are no objections, I will
check it next week.

Thanks.

-- 
H.J.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]