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Date: Thu, 13 Aug 2026 23:02:18 +0900
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Daniel Palmer <daniel@thingy.jp>
Cc: Hajime Tazaki <thehajime@gmail.com>, linux-mm@kvack.org,
	geert@linux-m68k.org, Arnd Bergmann <arnd@arndb.de>,
	"Matthew Wilcox (Oracle)" <willy@infradead.org>,
	Jan Kara <jack@suse.cz>, Andrew Morton <akpm@linux-foundation.org>,
	"Liam R. Howlett" <liam@infradead.org>,
	Lorenzo Stoakes <ljs@kernel.org>,
	Vlastimil Babka <vbabka@kernel.org>, Jann Horn <jannh@google.com>,
	Pedro Falcato <pfalcato@suse.de>, linux-fsdevel@vger.kernel.org
Subject: Re: [RFC PATCH 3/6] mm: nommu: fix an issue on map request to
 /dev/zero
Message-ID: <2026081308-amigo-paragraph-3afd@gregkh>
References: <20260813063401.1786548-1-thehajime@gmail.com>
 <20260813063401.1786548-4-thehajime@gmail.com>
 <2026081355-remold-sterility-84f9@gregkh>
 <CAFr9PX=zC8GnxwrR=wTwA4xQq89cHYpxZWooS+-=Q-WuNbjanQ@mail.gmail.com>
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On Thu, Aug 13, 2026 at 09:43:37PM +0900, Daniel Palmer wrote:
> Hi Greg,
> 
> On Thu, 13 Aug 2026 at 21:26, Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> 
> > Given the age of this issue, I don't think anyone uses no-mmu systems
> > anymore :(
> 
> There are a few of us using it for hobby stuff[0][1] and there are
> apparently people using it for actual commercial stuff.
> There was a session about this at LPC 2025...

This patch is fixing a very obvious issue that showed up in the 5.10
kernel, which was released in December 2020.

So I think the fact that no one has reported it before now means that no
one is actually using it :)

thanks,

greg k-h