Re: [PATCH v3 19/20] linux-user: permit RISC-V CFI dynamic entry in VDSO

[Richard Henderson]

On 8/7/24 10:06, Deepak Gupta wrote:
> RISC-V CFI use new processor-specific dynamic entry in ELF. Permit it in
> VDSO post-processing script.
>
> Signed-off-by: Jim Shu <jim.shu@sifive.com>
> Signed-off-by: Deepak Gupta <debug@rivosinc.com>
> ---
>   linux-user/gen-vdso-elfn.c.inc | 7 +++++++
>   1 file changed, 7 insertions(+)
>
> diff --git a/linux-user/gen-vdso-elfn.c.inc b/linux-user/gen-vdso-elfn.c.inc
> index 95856eb839..59c818eb11 100644
> --- a/linux-user/gen-vdso-elfn.c.inc
> +++ b/linux-user/gen-vdso-elfn.c.inc
> @@ -273,6 +273,13 @@ static void elfN(process)(FILE *outf, void *buf, bool 
> need_bswap)
>                   errors++;
>                   break;
>   
> +            case PT_LOPROC + 2:
> +                /* RISCV_ZICFILP_PLT: for RISC-V zicfilp extension */
> +                if (ehdr->e_machine == EM_RISCV) {
> +                    break;
> +                }
> +                goto do_default;

Documentation?  This symbol does not appear in either llvm or binutils sources.  I presume 
this is on a development branch somewhere.

The comment is poor.  Notice:

>               case PT_LOPROC + 3:
>                   if (ehdr->e_machine == EM_PPC64) {
>                       break;  /* DT_PPC64_OPT: integer bitmask */

the ppc64 comment describes the data payload.
As do the other comments beforehand.


r~