Re: [PATCHv9 4/5] sparc: Hook up execveat system call.

[David Drysdale]

On Wed, Nov 19, 2014 at 11:42 PM, Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
> Hi David,
>
> On Wed, 19 Nov 2014 17:27:51 +0000 David Drysdale <drysdale@xxxxxxxxxx> wrote:
>>
>> diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
>> index 580cde9370c9..15069cb35dac 100644
>> --- a/arch/sparc/kernel/systbls_64.S
>> +++ b/arch/sparc/kernel/systbls_64.S
>> @@ -88,6 +88,7 @@ sys_call_table32:
>>       .word sys_syncfs, compat_sys_sendmmsg, sys_setns, compat_sys_process_vm_readv, compat_sys_process_vm_writev
>>  /*340*/      .word sys_kern_features, sys_kcmp, sys_finit_module, sys_sched_setattr, sys_sched_getattr
>>       .word sys32_renameat2, sys_seccomp, sys_getrandom, sys_memfd_create, sys_bpf
>> +/*350*/      .word sys_execveat
>
> Shouldn't this be compat_sys_execveat?

Yeah, that would make sense -- thanks for spotting.

Looking at this more closely, I also wonder if we need a pair of wrappers
analogous to sys(32|64)_execve -- they include a (pipeline-executed)
flushw instruction after the jmpl to [compat_]sys_execve, which I guess
might be needed.  So I could add something like the following to
arch/sparc/kernel/syscalls.S:

  sys64_execveat:
      set sys_execveat, %g1
      jmpl %g1, %g0
      flushw
  #ifdef CONFIG_COMPAT
  sys32_execveat:
      set compat_sys_execveat, %g1
      jmpl %g1, %g0
      flushw
  #endif

However, I don't speak SPARC and can't run the code -- any thoughts
out there from someone who does & can?

Or maybe I should stop trying to be helpful with speculative patches, and
just leave wiring up the sparc stuff to the experts...

>>
>>  #endif /* CONFIG_COMPAT */
>
> --
> Cheers,
> Stephen Rothwell                    sfr@xxxxxxxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/