Re: [PATCH v3 3/3] S390: Fix gdbserver support for TDB

["Ulrich Weigand" <uweigand@de.ibm.com>]

Andreas Arnez wrote:
> On Wed, Dec 10 2014, Ulrich Weigand wrote:
> > This (and the related s390_fill_last_break change) is really an independent
> > change; maybe do it as a separate patch?  For consistency, we might likewise
> > want to allow regsets with NULL store_function (in regsets_fetch_inferior_registers).
> 
> OK, I will split the change to allow regsets with a NULL store_function
> and the exploitation for last_break out into a separate patch
> ("gdbserver: Support read-only regsets").
> 
> And for consistency I can also allow regsets with a NULL store_function.
> In that case I *think* we should suppress the invocation of ptrace with
> the regset's get_request in regsets_store_inferior_registers().  In
> other words, instead of read-modify-write we would then only do the
> write.  Agreed?

Ah, yes, the situation isn't symmetrical; I didn't think of that.

> In the original patch I omitted support for write-only regsets because I
> do not see a use case for this; and if there will be a use case in the
> future, I am not sure that the approach described above will really be
> appropriate.

Given that, it's probably best to indeed wait until we have a use case
(if ever), so I withdraw my suggestion.

Thanks,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU/Linux compilers and toolchain
  Ulrich.Weigand@de.ibm.com