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Date:   Sun, 11 Feb 2018 23:25:56 +0000
From:   Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     Mark D Rustad <mrustad@gmail.com>,
        Adam Borowski <kilobyte@angband.pl>,
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        Ingo Molnar <mingo@kernel.org>,
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Subject: Re: [PATCH 00/31 v2] PTI support for x86_32
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On Sun, 11 Feb 2018 11:42:47 -0800
Andy Lutomirski <luto@amacapital.net> wrote:

> On Feb 11, 2018, at 9:40 AM, Mark D Rustad <mrustad@gmail.com> wrote:
> 
> >> On Feb 11, 2018, at 2:59 AM, Adam Borowski <kilobyte@angband.pl> wrote:
> >>   
> >>> Does Debian make it easy to upgrade to a 64-bit kernel if you have a
> >>> 32-bit install?  
> >> 
> >> Quite easy, yeah.  Crossgrading userspace is not for the faint of the heart,
> >> but changing just the kernel is fine.  
> > 
> > ISTR that iscsi doesn't work when running a 64-bit kernel with a 32-bit userspace. I remember someone offered kernel patches to fix it, but I think they were rejected. I haven't messed with that stuff in many years, so perhaps the userspace side now has accommodation for it. It might be something to check on.
> >   
> 
> At the risk of suggesting heresy, should we consider removing x86_32 support at some point?

Probably - although it's still relevant for Quark. I can't think of any
other in-production 32bit only processor at this point. Big core Intel
went 64bit 2006 or so, atoms mostly 2008 or so (with some stragglers that
are 32 or 64 bit depending if it's enabled) until 2011 (Cedartrail)

If someone stuck a fork in it just after the next long term kernel
release then by the time that expired it would probably be historical
interest only.

Does it not depend if there is someone crazy enough to maintain it
however - 68000 is doing fine 8)

Alan