[PATCH v13 1/8] parisc: Drop parisc special case for __sighandler_t

[Peter Collingbourne]

On Wed, Nov 4, 2020 at 9:24 AM Catalin Marinas <catalin.marinas at arm.com> wrote:
>
> On Wed, Nov 04, 2020 at 10:54:34AM -0600, Eric W. Biederman wrote:
> > Peter Collingbourne <pcc at google.com> writes:
> > > From: Helge Deller <deller at gmx.de>
> > >
> > > I believe we can and *should* drop this parisc-specific typedef for
> > > __sighandler_t when compiling a 64-bit kernel. The reasons:
> > >
> > > 1. We don't have a 64-bit userspace yet, so nothing (on userspace side)
> > > can break.
> > >
> > > 2. Inside the Linux kernel, this is only used in kernel/signal.c, in
> > > function kernel_sigaction() where the signal handler is compared against
> > > SIG_IGN.  SIG_IGN is defined as (__sighandler_t)1), so only the pointers
> > > are compared.
> > >
> > > 3. Even when a 64-bit userspace gets added at some point, I think
> > > __sighandler_t should be defined what it is: a function pointer struct.
> > >
> > > I compiled kernel/signal.c with and without the patch, and the produced code
> > > is identical in both cases.
> > >
> > > Signed-off-by: Helge Deller <deller at gmx.de>
> > > Reviewed-by: Peter Collingbourne <pcc at google.com>
> > > Link:
> > > https://linux-review.googlesource.com/id/I21c43f21b264f339e3aa395626af838646f62d97
> >
> > Peter as you have sent this, this also needs your Signed-off-by.
> >
> > Otherwise this looks reasonable to me.
> > Acked-by: "Eric W. Biederman" <ebiederm at xmission.com>

Thanks, likewise for the other patches that you acked.

> > While the final bits look like they are still under discussion it looks
> > like the preceding cleanups are pretty solid at this point.
>
> Minor nits, unless you nak the whole approach of SA_FAULTFLAGS and
> SA_UNSUPPORTED ;) (it looks a bit complicated to me but I don't have a
> better idea for a generic implementation).
>
> > Any chance we can get the cleanups into a tree in linux-next so that
> > the discussion can focus on the core parts of this work?
> >
> > Perhaps I should pick up the clenaups?
>
> However you prefer (I usually start queuing patches at -rc3). If you
> pick them up, please provide a stable branch somewhere so that we can
> add the others on top.

Picking up the cleanups first sounds good to me and I don't mind which
tree they go via. To make it easier to pick up just the cleanups I
will reorder the patches a bit. I will move patch 6 to patch 4 so that
1-4 are the non-uapi-affecting cleanups and 5-8 implement the
substantive changes.

Peter