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Subject: Re: Can we drop upstream Linux x32 support?
To:     Andy Lutomirski <luto@kernel.org>
Cc:     X86 ML <x86@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Borislav Petkov <bp@alien8.de>,
        Florian Weimer <fweimer@redhat.com>,
        Mike Frysinger <vapier@gentoo.org>,
        "H. J. Lu" <hjl.tools@gmail.com>, Rich Felker <dalias@libc.org>,
        x32@buildd.debian.org, Arnd Bergmann <arnd@arndb.de>,
        Will Deacon <will.deacon@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
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From:   =?UTF-8?Q?Thomas_Sch=c3=b6bel-Theuer?= <thomas@schoebel-theuer.de>
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Date:   Fri, 14 Dec 2018 22:41:20 +0100
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On 12/14/18 22:24, Andy Lutomirski wrote:
> I should clarify again: I am not suggesting that we drop 32-bit
> support in the forseeable future.  (Well, I might eventually suggest
> that we drop support for 32-bit *hardware* at some point, but not for
> 32-bit compat software.)  Linux's compat code is quite robust and is
> even fairly maintainable.
>
> I'm talking about x32, which is a different beast.
>
OK, this does not really make a big difference for large-scale 
enterprise users. Some day in the very distant future any legacy system 
will disappear, eventually.

So from my viewpoint the mentioned roadmap / timing requirements will 
remain the same, whatever you are dropping.

Enterprise-critical use cases will probably need to be migrated to 
KVM/qemu together with their old kernel versions, anyway (because the 
original hardware will be no longer available in a few decades).