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Date: Sun, 5 Jul 2026 22:23:43 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Matthew Wilcox <willy@infradead.org>
Cc: Hajime Tazaki <thehajime@gmail.com>, liam@infradead.org, ljs@kernel.org,
 vbabka@kernel.org, jannh@google.com, pfalcato@suse.de, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org, Greg Ungerer <gerg@uclinux.org>
Subject: Re: [PATCH] mm: nommu: point to the write iterator upon split_vma
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On Mon, 6 Jul 2026 04:58:28 +0100 Matthew Wilcox <willy@infradead.org> wrote:

> On Sun, Jul 05, 2026 at 03:27:08PM -0700, Andrew Morton wrote:
> > Thanks.  Unfortunately we aren't very diligent about the nommu code
> > (are we?).   Perhaps appropriately - clearly this code doesn't get used a
> > lot.
> 
> Should we delete support for NOMMU?  As you say, it doesn't get much
> testing, or presumably usage.  I have this quote from #m68k a couple of
> years ago...

Greg is busily developing kernel code.

> : I looked at nommu very briefly when I had my 68000 board on the bench
> : but didn’t get anywhere. Also didn’t try particularly hard. I think
> : you are better off with fuzix or OS9 if you want something unixy.
> 
> (i suspect Zephyr would also be good, but it doesn't support m68k, just
> arc, arm, arm64, mips, openrisc, renesas rx, riscv, sparc, x86 and xtensa)

Greg, how mush use is NOMMU Linux seeing nowadays?

Thanks.