From nobody Mon Sep 2 01:39:24 2024 X-Original-To: freebsd-stable@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Wxryv1V7qz5TZs2 for ; Mon, 02 Sep 2024 01:39:35 +0000 (UTC) (envelope-from jamie@catflap.org) Received: from donotpassgo.dyslexicfish.net (donotpassgo.dyslexicfish.net [IPv6:2001:19f0:7400:8808:123::1]) by mx1.freebsd.org (Postfix) with ESMTP id 4Wxrys1xzYz4bS9 for ; Mon, 2 Sep 2024 01:39:32 +0000 (UTC) (envelope-from jamie@catflap.org) Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=pass (policy=none) header.from=catflap.org; spf=pass (mx1.freebsd.org: domain of jamie@catflap.org designates 2001:19f0:7400:8808:123::1 as permitted sender) smtp.mailfrom=jamie@catflap.org X-Catflap-Envelope-From: X-Catflap-Envelope-To: Received: from donotpassgo.dyslexicfish.net (donotpassgo.dyslexicfish.net [209.250.224.51]) by donotpassgo.dyslexicfish.net (8.14.5/8.14.5) with ESMTP id 4821dOws070961 for ; Mon, 2 Sep 2024 02:39:24 +0100 (BST) (envelope-from jamie@donotpassgo.dyslexicfish.net) Received: (from jamie@localhost) by donotpassgo.dyslexicfish.net (8.14.5/8.14.5/Submit) id 4821dOrY070960 for freebsd-stable@freebsd.org; Mon, 2 Sep 2024 02:39:24 +0100 (BST) (envelope-from jamie) From: Jamie Landeg-Jones Message-Id: <202409020139.4821dOrY070960@donotpassgo.dyslexicfish.net> Date: Mon, 02 Sep 2024 02:39:24 +0100 Organization: Dyslexic Fish To: freebsd-stable@freebsd.org Subject: mount -u removes "noatime" User-Agent: Heirloom mailx 12.4 7/29/08 List-Id: Production branch of FreeBSD source code List-Archive: https://lists.freebsd.org/archives/freebsd-stable List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: freebsd-stable@freebsd.org Sender: owner-freebsd-stable@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.2.7 (donotpassgo.dyslexicfish.net [209.250.224.51]); Mon, 02 Sep 2024 02:39:24 +0100 (BST) X-Spamd-Bar: --- X-Spamd-Result: default: False [-3.33 / 15.00]; NEURAL_HAM_MEDIUM(-0.98)[-0.980]; NEURAL_HAM_LONG(-0.93)[-0.928]; NEURAL_HAM_SHORT(-0.72)[-0.723]; DMARC_POLICY_ALLOW(-0.50)[catflap.org,none]; R_SPF_ALLOW(-0.20)[+mx:dyslexicfish.net]; MIME_GOOD(-0.10)[text/plain]; RCVD_NO_TLS_LAST(0.10)[]; FREEFALL_USER(0.00)[jamie]; RCPT_COUNT_ONE(0.00)[1]; HAS_ORG_HEADER(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:20473, ipnet:2001:19f0:7400::/38, country:US]; MLMMJ_DEST(0.00)[freebsd-stable@freebsd.org]; PREVIOUSLY_DELIVERED(0.00)[freebsd-stable@freebsd.org]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; R_DKIM_NA(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; TO_DN_NONE(0.00)[]; ARC_NA(0.00)[] X-Rspamd-Queue-Id: 4Wxrys1xzYz4bS9 I noticed some of my noatime mounts keep being reset to atime. Looking further, I found out the culprit was a snapshotting program running: mount -u -o snapshot It turns out, that just using -u causes noatime to be dropped: | root@catflap# mount -v | grep da0p3 | /dev/da0p3 on / (ufs, local, noatime, writes: sync 3343750 async 2795680, reads: sync 204356 async 10254, fsid 1fa69665dd23d4e8, vnodes: count 3803 ) | root@catflap# mount -u / | /dev/da0p3 on / (ufs, local, writes: sync 3343750 async 2795680, reads: sync 204356 async 10254, fsid 1fa69665dd23d4e8, vnodes: count 3803 ) I assume this shouldn't be the case? Incidentally, is there any difference between "mksnap_ffs" and "mount -u -o snapshot..."? (other that the noatime mangling) Finally, man mount(8) has: | Note that the schg flag is set on snapshots to ensure that not even the root | user can write to them. The unlink command makes an exception for snapshot | files in that it allows them to be removed even though they have the schg | flag set, so it is not necessary to clear the schg flag before removing a | snapshot file. The schg flag isn't set on snapshots, at least according to ls -lo Cheers, Jamie