Re: [PATCH v4 2/2] x86: Start removing X86_X32_ABI

[Sebastian Andrzej Siewior <sebastian@breakpoint.cc>]

On 2026-10-09 20:13:55 [-0600], Tancred wrote:
> 
> 
> On 10/8/26 03:07, Sebastian Andrzej Siewior wrote:
> > where certain workloads widely
> > move to x32 and use it exclusively. In the meantime Debian introduced a
> > patch to disable x32 by default (so it has to be enabled at boot time on
> > the command line) because they are afraid of the increased attack
> > surface. Fedora as far as I tell has X32 disabled (looking at 7.0-rc5
> > rpm in rawhide).
> > 
> > Since there is practically no real use for x32
> 
> I only recently discovered x32 and built a Desktop (with all daemons and
> utilities running 10-30% smaller and some a bit faster, with 64 bit
> libraries for eg. Firefox.) My experiment should definitely not decide
> anything, but how much real-world use would be sufficient to justify
> continued presence (more complex compat code)?

"a bit faster" needs actual numbers to justify. One examples was quicker
gcc but I don't see a x32 compile farm leveraging this benefit.
Smaller binaries sounds like a benefit from storage point of view but
then if you need also 64bit binaries (and libs) for things like firefox
then the advantage is probably more than gone.
Also, Adrian keeps pointing out that Debian has a Debian port of x32.
Without an official release (and installer) there will not be security
updates of packages. Without security updates for a "stable release" one
is stuck with Sid which has "latest" of all packages. That is usually
not something for non-developers.

> - Alex Alejandre

Sebastian