From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 B31D913B7A3 for ; Mon, 6 Jul 2026 03:58:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783310317; cv=none; b=c4coTjQKpkYRIp3PSjeMSfWv0xS/CGWnENi4NNHfE1ns169pGJpT0bRgtw7bP0QaZ2pualdE6o4Y7gFRQpAFvgWxTrgXzWPyOZwSaBrqqRC0yslus/PWiZXRuTUBRlRvcMxXSEQsZVJ+dWejjFiNN73JjTXkCMep7A9bqmwnNhs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783310317; c=relaxed/simple; bh=J8CSA0yzbOEMlfmaP83onLuAc5CmgWMnXji3+vAc8Ig=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=I9x7tlqf+mwd9hicz2NOvQp92XkfYCj3utmw1CeDo/3YdyXQ7eNd21t6rV9YGfmRfC/5d2jTmFB0iJ33tNmd/INpXcylH8lslp7jkvZXNEXDUr27JbRQWTs9NwhaKIe804sB72ghUejSj8GnxLNQBqKQjnDvG1iQ1PLu0hIGlHY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=e5AadE2f; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="e5AadE2f" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=oPT5GCvBZJJjoFBxUutZLl6TvHZ6APGzDMMZtlpoCkw=; b=e5AadE2fcatFwDztki5HGa+1/w ruYgTHD6EzgtoCJFe8FDTdnLA3F3wPwBrKOjvHa7Cd9k2CId4eJNzllfe2WPVV9rBRnQ2fI3KpsSI BFmEx/25BqsNOM2ttPLVOiUIjmgGxWW1XIdxkpAYjm7xwMB32fbTG2J9aw4IIF2d0vgvTeNqupAc6 NFVZ/nmN2C3ZyYDVu9+DK6C+wp53CCbC/8GO7Z9svPt4t1a9Z5RqWKsYEfqE5mcT9UoT3277OFawh ubWmItj47cMWlq/w2FsSgxtNJY1iKy19UcvtUN04qT3/z+gdQ9TQUhXrQ3spVbrGqLFEEsk/uK6Gj GcGv2VxQ==; Received: from willy by casper.infradead.org with local (Exim 4.99.1 #2 (Red Hat Linux)) id 1wgaTU-0000000FA9e-1f9p; Mon, 06 Jul 2026 03:58:28 +0000 Date: Mon, 6 Jul 2026 04:58:28 +0100 From: Matthew Wilcox To: Andrew Morton Cc: Hajime Tazaki , liam@infradead.org, ljs@kernel.org, vbabka@kernel.org, jannh@google.com, pfalcato@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: nommu: point to the write iterator upon split_vma Message-ID: References: <20260702012546.665383-1-thehajime@gmail.com> <20260705152708.582fd8d87561f600da23c0a7@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260705152708.582fd8d87561f600da23c0a7@linux-foundation.org> 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... : 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)