From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 CB7F61494CC; Fri, 10 Oct 2025 05:27:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760074081; cv=none; b=nUq47Nth6bYpGOIXO5ddPz5p5Ergj0k1YSybo9jbbXKudOyxN4oNWDq++e0taGrCJ5jF8eRpnFmhNO8H4APbZVuFGPCncameTgcgfKNj6G+v1p3MdFw9WOKEDMP6fCq3anV9BIY7/xOIUlXJSa9Y7+GTjQz0JZDa596g937T/GU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760074081; c=relaxed/simple; bh=mDGmi3+Wa36bqb6hX02bN3onFxey1pLGTUWruEAOyX8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qQgFS2Y8BLj7tI6j95IIWXkLYEMH5CEcNgQFZT8TPajokH1P+pKJ5h1IVu5ZGAI72HlKJSrEHN3xx5ugurQuPGm2hbdFFK6FtGvvu+u7pM/tV4Bv+F3d5L+ThWrluWKQK/a0M0XOh3JrQOvM4UGZ7rkjKyHOv+n/CKJav+A+btU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=OpiCnd/J; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OpiCnd/J" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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=yWCrP/oYlMAZ7QVzoZ7F/7mx1aOjPJpsMFlqIpG86h8=; b=OpiCnd/Jqy1af1tAwRQ4Qpyh+8 F++KMdLENM6ks6AvSoUSYtgsC8KojVVV49pzb4vkeqlPa6b149RQHZic1gRVMj9hCeo6lb60MxN3T hFl14gI6LGbmagzn1SYlBgZJe+vpAS8C7G+HMNnRLYgIHGkRcX+wlLrQW5nGIh7MieTX2Jh9nRvaZ Nvhu7UAck0WWV8nSBM/8Ku2ZZ/DreBNJVp65+Vx4d9+Bk1DacjZBahGuiEGr/KikKG2IgzCRczl0c rLOIxSHyAvePYkgeC6XFzYT2fHGivhAsAlQTxSsA3LseEpOZH3cNM8KgfDxtGVjXHhEnxbtbl+MJx vLBpOmKg==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1v75fb-00000007iAF-17zR; Fri, 10 Oct 2025 05:27:59 +0000 Date: Thu, 9 Oct 2025 22:27:59 -0700 From: Christoph Hellwig To: Andy Lutomirski Cc: Christoph Hellwig , Pavel Emelyanov , linux-fsdevel@vger.kernel.org, "Raphael S . Carvalho" , linux-api@vger.kernel.org, linux-xfs@vger.kernel.org Subject: Re: [PATCH] fs: Propagate FMODE_NOCMTIME flag to user-facing O_NOCMTIME Message-ID: References: <20251003093213.52624-1-xemul@scylladb.com> Precedence: bulk X-Mailing-List: linux-api@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: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Oct 08, 2025 at 08:22:35AM -0700, Andy Lutomirski wrote: > On Mon, Oct 6, 2025 at 10:08 PM Christoph Hellwig wrote: > > > > On Sat, Oct 04, 2025 at 09:08:05AM -0700, Andy Lutomirski wrote: > > > > Well, we'll need to look into that, including maybe non-blockin > > > > timestamp updates. > > > > > > > > > > It's been 12 years (!), but maybe it's time to reconsider this: > > > > > > https://lore.kernel.org/all/cover.1377193658.git.luto@amacapital.net/ > > > > I don't see how that is relevant here. Also writes through shared > > mmaps are problematic for so many reasons that I'm not sure we want > > to encourage people to use that more. > > > > Because the same exact issue exists in the normal non-mmap write path, > and I can even quote you upthread :) The thread that started this is about io_uring nonblock writes, aka O_DIRECT. So there isn't any writeback to defer to.