Re: [Qemu-devel] Drop support for 32bit hosts in qemu?

[Daniel P . Berrangé]

On Wed, Jun 27, 2018 at 03:02:48PM +0200, Juan Quintela wrote:
> Markus Armbruster <address@hidden> wrote:
> > Thomas Huth <address@hidden> writes:
> >
> >> On 27.06.2018 08:51, Gerd Hoffmann wrote:
> > [...]
> >>> Drop support for 32bit hosts in qemu?
> >>
> >> I guess the only way to answer that question reliably is to send a patch
> >> to mark 32-bit hosts as deprecated...
> >>
> >> Anyway, you still have got to fix that problem with -m32 now somehow
> >> since we certainly can not drop 32-bit immediately.
> >
> > We certainly can if we want to.
> >
> > Our formal deprecation policy codifies our compromise between the need
> > to evolve QEMU and the need of its users for stable external interfaces.
> >
> > "Compiles on host X" is also a need, but it's a different one.
> > Evidence: "Supported build platforms" has its own appendix, separate
> > from "Deprecated features".  It's mum on 32-bit hosts.
> >
> > I'm not saying we *should* drop 32-bit hosts immediately.  Only that the
> > feature deprecation policy does not apply.
> >
> > Is QEMU still useful on 32-bit hosts?  Honest question!
> 
> At least require 32bits architectures/compilers able to use 64bit
> atomics.  That leaves us with x86 (depending on compiler).  And there
> haven't been 32bit x86 hosts since .....

....the most recent machine you bought, since the Intel ME is running
on some kind of i486-like CPU behind the back of your main CPU ;-P

Regards,
Daniel
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