Re: Drop support for x86-32

From: Martin Nybo Andersen
Date: Fri Aug 24 2012 - 14:10:27 EST


On Friday 24 August 2012 19:05:53 wbrana wrote:
> On 8/24/12, Martin Nybo Andersen <tweek@xxxxxxxx> wrote:
> > What I'd hate even more is rendering my old working hardware useless by
> > removing x86-32 support from the kernel. To reason the removal by saying
> > "Microsoft plans to do it" just makes me go bonkers...
>
> Your old hardware will work fine with long term kernel.

That's right, but new hardware, that I wish to use with the old machines might
not because of no backporting of new drivers. Same goes for new software
utilising newer kernel features.

> > These legacy apps will most likely be compiled for x86-32 and not x32 (an
> > argument for not removing x86-32 support on a running x86-64 kernel).
>
> Which legacy apps do you mean?

Those mentioned by Chris Friesen, whose arguments you apparently ignored.

Going back to your original arguments:
> x86-32
> - is deprecated since Linux supports X32.
No. X32 is merely yet another ABI supported by Linux.

> - will slow down adoption of X32
Perhaps. But that would rather be because of low benefits offered by x32 (not
being able to run on legacy hardware is not a benefit (and not its
intension)).

> - there won't be X32 versions of many software
You are allowed to compile most of the software running on Linux yourself. If
you want a binary to use the x32 ABI, go compile.

> - if new ABI was added, old one should be removed
No. If kernel.org runs out of diskspace, I'd rather sponsor some new disks.
And, x32 is an ABI for the x86-64 architecture, while x86-32 is an
architecture in itself.

> - wastes time of developers who can spend their time supporting X32
> instead of x86-32 or support x86-64 only as 99% of users will be able
> to run x86-64 software if x86-32 will be dropped
No. If, for instance, an m68k maintainer/developer stops maintaining m68k
support, nobody is telling him to continue his works on, say, sparc or
whatever hyped architecture.

In other words: It costs exactly *nothing* for us to have x86-32 support. What
is does cost, though, is the maintainers/developers spare time and goodwill.
Something we all should appreciate.

> - wouldn't be dropped this year, but there should be plan when it will
> be dropped e.g. when Windows 9 will be released
No. That plan will come automagically when x86-32 is not used anymore and when
somebody works on a patch to remove x86-32 support.

--
Cheers,
Martin
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