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Date:   Sun, 23 Oct 2022 22:44:22 +0800
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To:     Linus Torvalds <torvalds@linux-foundation.org>,
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From:   David Gow <david@davidgow.net>
Subject: Re: [PATCH v14 08/14] mm: multi-gen LRU: support page table walks
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Le 22/10/22 à 00:50, Linus Torvalds a écrit :
> On Thu, Oct 20, 2022 at 8:38 PM Matthew Wilcox<willy@infradead.org>  wrote:
>> On Thu, Oct 20, 2022 at 07:10:46PM -0700, Linus Torvalds wrote:
>>> We got rid of i386 support back in 2012. Maybe it's time to get rid of
>>> i486 support in 2022?
>> Arnd suggested removing i486 last year and got a bit of pushback.
>> The most convincing to my mind was Maciej:
> Hmm. Maciej added to the cc.
> 
> I suspect we can just say "oh, well, use LTS kernels".
> 

To jump in early on the inevitable pile-on, I'm doing my occasional 
32-bit x86 KUnit test runs on an old 486 DX/2. Now, this is _mostly_ 
just a party trick -- and there are lots of people running 32-bit builds 
under QEMU et al -- but personally, the only non-amd64-capable x86 
machines I have lying around are all 486 class (including a new Vortex86 
board).

(But, at the very least, I can confirm that the latest torvalds/master 
does build, run, and pass KUnit tests on a real 486 at the moment.)

So while dropping i486 wouldn't affect anything particularly important 
for me, it'd be a minor inconvenience and make me a bit sad.

That being said, I have no objection to dropping support for 486SX CPUs 
and CONFIG_MATH_EMULATION.

Cheers,
-- David