From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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.lore.kernel.org (Postfix) with ESMTPS id 6EAF6C83F1A for ; Mon, 14 Jul 2025 17:39:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pob3xibbFtM0VnCu/LeXClpl3A6/0vjvNJWjLi6J/bY=; b=AQwogRG1ju2Xc93ENmMcLTCR/S luX560uh9f1ehI794soo0QJssSDjiVqQwV16tUbpA5+wHh12LOGKb58SHjB5qbspN7G2uSorWGntm kdfLMpF8vw6WDLNCFAUea6MY/OqkVMbfjLRxD1N+Qrb2MLcGQtjVeeJ4d+m0uPLtBNg+yAaPtFkwA 3Lb/ZvLtq1ach/Vf23RouEiOJfYAiBXBDxVn4/7zxKFCOVDvbgjD8GAVdw6pxAuLA2CngTcxL97MD v1t1efN3GUc/LXzdrXecS1NI/riX6aiALfqU9z76NsXB5gV/C8OJTLz2JL2yusJbwdzfml387JZht x1dLkbYA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ubN9Y-00000002zB3-3wdi; Mon, 14 Jul 2025 17:39:48 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ubLes-00000002mqy-2IkA for linux-nvme@lists.infradead.org; Mon, 14 Jul 2025 16:04:04 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id AC8E7A57290; Mon, 14 Jul 2025 16:04:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52AA6C4CEF0; Mon, 14 Jul 2025 16:04:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752509041; bh=AHdmcwDk69P0bsuDXUAUbKZgYi6IjvT1mhl/qsg2pFw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=G/0Zk/DlO4/RGceMRxhdRCcVamfcty52cZZds5h1ZtTGD1N/s0qVnZzVVIKATF5ZN fcnomUp7Nkq/zyNgKumD3M1G+Ba7iz7qM4ukSEeQB75MYfTZoKNX0vcb2QdXttFS2L yEtEAIY1YMM8L4JsLctZ7G8gMSB5Wy1ElbNlTRaLV1zsdR5pwSWVatXFVbLKiEffB7 2avLGgmbKkY6WRDjGX5P50O45SlosYxfPpw8BB3BI3NPNRmirTrqANymHNgHm7sm7F J44cYxkml4vMF/IHRcuS6CF2UwQF5rjPTCMuiXqUU9w7o5umLg8GnMKhjtrTJ9GzeW RknHjdOMVGf4Q== Date: Mon, 14 Jul 2025 09:04:00 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: Theodore Ts'o , John Garry , linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org Subject: Re: Do we need an opt-in for file systems use of hw atomic writes? Message-ID: <20250714160400.GK2672049@frogsfrogsfrogs> References: <20250714131713.GA8742@lst.de> <20250714132407.GC41071@mit.edu> <20250714133014.GA10090@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250714133014.GA10090@lst.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250714_090402_653532_0416F423 X-CRM114-Status: GOOD ( 16.96 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Mon, Jul 14, 2025 at 03:30:14PM +0200, Christoph Hellwig wrote: > On Mon, Jul 14, 2025 at 09:24:07AM -0400, Theodore Ts'o wrote: > > > Is is just me, or would it be a good idea to require an explicit > > > opt-in to user hardware atomics? > > > > How common do we think broken atomics implementations; is this > > something that we could solve using a blacklist of broken devices? > > I don't know. But cheap consumer SSDs can basically exhibit any > brokenness you can imagine. And claiming to support atomics basically > just means filling out a single field in identify with a non-zero > value. So my hopes of only seeing it in a few devices is low, > moreover we will only notice it was broken when people lost data. Do you want to handle it the same way as we do discard-zeroes-data and have a quirks list of devices we trust? Though I can hardly talk, knowing the severe limitations of allowlists vs. product managers trying to win benchmarks with custom firmware. :( --D