From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8473A2472B6 for ; Thu, 13 Aug 2026 13:43:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786628617; cv=none; b=MtjOW+2r/TvJQCBFI7swww3MkIDqHFnXaNl6+XKJsLWqmls2jfj4MeyGU/hxoWXkYkZTJOlArswiiJ3pxr3q+HPNyJTNjlFh5trTxDvXW/qWQrOsIQOgilGZKG3jPATgaPLdqhAxCi1JsCeM1f7kqSr/Bjn6bnYFk/Ac9qdclCI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786628617; c=relaxed/simple; bh=WAHSyVZsm9YXO0RmUNpzPqO0wNYBSTgob7pwAZgh2Oo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LUN7Z9LXSPFKBAugFnKt6niebZUEBukNxtlEvxXPjNrBe2miWlNERcAeuPK9eux02NOuIidYj7D0iRzm5ivefS42H2H6js+En1dEokyiZsfZ3XfqHVm230N8d7kl+c9Xx3h1Vxl9ruTkofwftONXuF1oWdSAzEY4N9QYbnOSBnA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IqFpH2CS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IqFpH2CS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6C7D1F000E9; Thu, 13 Aug 2026 13:43:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786628616; bh=WAHSyVZsm9YXO0RmUNpzPqO0wNYBSTgob7pwAZgh2Oo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=IqFpH2CSq9p9bZR2i5Y4nqzZOu7/zIMm7Iez7N30zxLzo/UKHOkmIEB92KVNtmyC6 LIJxCaR/sgEkr3lEFG/B1ATruQUTEI3JpcV8Wf3YSHjFi68ieH/1ciWkveUnIz457g 6zZK5UeOjOZ3BXnJpdG0ofWa6EXcdBUvXZ7wSlzDqtwn6bobxllc0oMqunKMCYD3XP OkLHdQ2hhWrX7wMZdX/8K7oVIT+LtPVwY163C8IALm+c9cbu7UUAhlCY2eJzI116yR +/yMSSC8DfNRa29FAz39Z1APfy0F/8caGDrWDAsZOOMkkZWyi1fcdkTQeJQSE74mHj kxkpqFE72yKxA== Date: Thu, 13 Aug 2026 14:43:16 +0100 From: "Lorenzo Stoakes (ARM)" To: Matthew Wilcox Cc: Greg Kroah-Hartman , Hajime Tazaki , linux-mm@kvack.org, geert@linux-m68k.org, daniel@thingy.jp, Arnd Bergmann , Jan Kara , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , linux-fsdevel@vger.kernel.org Subject: Re: [RFC PATCH 3/6] mm: nommu: fix an issue on map request to /dev/zero Message-ID: References: <20260813063401.1786548-1-thehajime@gmail.com> <20260813063401.1786548-4-thehajime@gmail.com> <2026081355-remold-sterility-84f9@gregkh> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Aug 13, 2026 at 02:32:27PM +0100, Lorenzo Stoakes (ARM) wrote: > I do agree with Greg however that nommu is something we should get rid of. See > my other reply here. Sorry this was an overreach - Greg didn't say that :) I mean Greg asked if anybody uses nommu, the answer is yes, but the real question I think is 'is anybody using a very recent kernel who couldn't either use an older one or maintain a downstream kernel'. And to that I think the answer is absolutely not. And if the answer were yes - you must surely be a company with a product (security concerns on a nommu system is a debatable concept) - and then you need to put up or shut up IMO. -- Cheers, Lorenzo