Remove ppc32 support

[Al Dunsmuir]

On Friday, May 16, 2014, 4:41:51 PM, Josh Boyer wrote:
> On Fri, May 16, 2014 at 3:12 PM, Al Dunsmuir <al.dunsmuir at sympatico.ca> wrote:
>> On Friday, May 16, 2014, 2:50:15 PM, Josh Boyer wrote:
>>> On Fri, May 16, 2014 at 2:37 PM, Al Dunsmuir <al.dunsmuir at sympatico.ca> wrote:
>>>> On Friday, May 16, 2014, 12:22:26 PM, Josh Boyer wrote:

>> I  know  someone  who has sparc, alpha hardware.  I'm not sure if they
>> have an ia64 box taking up space in a closet somewhere.

> Great.  I know someone that has the hardware too.  We still removed
> support for both in the kernel spec because it was entirely moribund.
That is reasonable.

> Hardware availability is often secondary to sustained effort from
> people that have that hardware.  History shows that people seem less
> interested in keeping it running when they have to do the work or go
> it alone in doing the work.
Human nature.  We'll hope there is a different outcome.


>>>> Making  it  so  that ppc32 does not get built by default is one thing,
>>
>>> Actually, it's a very very big thing.  Those wishing to keep it alive
>>> now need to come up with their own build hardware and build enviroment
>>> setup.  This is by far the largest hurdle, and if it isn't done
>>> quickly the ppc32 secondary-secondary (thirdary?) arch will quickly
>>> fall behind and into disrepair.
>> Some  folks  have  volunteered  to  host the builds, and provide build
>> hardware. We'll see how that works out. If we do have to build outside
>> the Fedora systems, there are going to be security considerations.

> Outside build systems are probably going to be a requirement here.
> That is how ARM started, so it's not unreasonable.  I doubt you're
> going to get Fedora Infrastructure to host any ppc32 hardware in the
> colo due to both space and configuration issues (they only take rack
> machines).

We  need  to  see  what  can be done to make sure we can stay "Fedora"
under  those  circumstances.  Being  forced  to be a Fedora-like remix
would be a shame if that is the only issue.

>>>> but  removing  the  ability to build ppc32 at all seems excessive, and
>>>> certainly premature given the current situation.
>>
>>> Which is why I sent it as a patch instead of simply committed it.
>>> Discussion is requested.  At a minimum though, I really would like to
>>> drop the -smp flavor because it was of very limited use even when ppc
>>> was a primary arch and it adds the most complication to the spec.
>>
>> Thanks for clarifying that.
>>
>> The  problem  with  dropping smp is that I and other have smp hardware
>> that  we  would  like  to  use.  That is also likely the hardware that

> Yes, I've seen that.  I'm willing to hold off on the removal for a bit
> to see how quickly your effort gets off the ground.  I won't wait
> forever though.

Entirely reasonable.

> To be clear, whatever is built is entirely supported by the team doing
> the ppc32 work.  Any bugs filed in Fedora bugzilla will get assigned
> to the contact person.

That's  pretty well the way it is with ARM even now, whether they like
it or not.

There  is  likely  to be a rare occasion when ppc32 discovers an issue
that  also  affects  other  builds.  Reproducing on on X86, X86_64, or
ppc64  should  allow  the  problem  to  be  addressed  by  the regular
developers.

Worst  case,  providing  a  remote  login  seems  to  be  the standard
approach.

>> would  best  be  used  for builds, should "build native" and lack of a
>> ppc32 cross compiler & binutils mean we can's use a ppc64 build host.

> Cross-compiling is not allowed in Fedora anyway.  Which is really
> unfortunate because it is actually a very useful thing to do in
> situations just like this.

That  is  the  rule  for  release  builds,  but  like  ARM (and ARM64)
sometimes you have to use cross-compilation during bring up.

Unlike  ARM,  ppc64  does support user processes running in ppc32 mode
(via  multi-arch).  Do  the  current (up to today) ppc32 builds run on
ppc32 hardware, or do they run on ppc64 machines via multi-arch?

If there is ppc32-only hardware, why can't we continue to use it?