linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andy Lutomirski <luto@amacapital.net>
Cc: David Howells <dhowells@redhat.com>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	John Johansen <john.johansen@canonical.com>,
	Tejun Heo <tj@kernel.org>,
	selinux@tycho.nsa.gov, Paul Moore <paul@paul-moore.com>,
	Li Zefan <lizefan@huawei.com>,
	linux-api@vger.kernel.org, apparmor@lists.ubuntu.com,
	Casey Schaufler <casey@schaufler-ca.com>,
	fenghua.yu@intel.com,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Eric Biggers <ebiggers@google.com>,
	linux-security-module@vger.kernel.org,
	Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Stephen Smalley <sds@tycho.nsa.gov>,
	tomoyo-dev-en@lists.sourceforge.jp, cgroups@vger.kernel.org,
	torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org, "Theodore Y. Ts'o" <tytso@mit.edu>,
	Miklos Szeredi <miklos@szeredi.hu>
Subject: Re: BUG: Mount ignores mount options
Date: Sat, 11 Aug 2018 17:51:24 +0100	[thread overview]
Message-ID: <20180811165123.GH6515@ZenIV.linux.org.uk> (raw)
In-Reply-To: <9B6E2781-484B-4C42-95F5-F900EA36CEA5@amacapital.net>

On Sat, Aug 11, 2018 at 09:31:29AM -0700, Andy Lutomirski wrote:

> I don’t see why we need all this fancy “do the options match” stuff.  For the handful of filesystems (like NFS) that do something intelligent when multiple non-bind mount requests against the same underlying storage happen,  we can keep that behavior in the new API. For other filesystems that don’t have this feature, we should simply fail the request.

> IOW I see so compelling reason to call sget() at all from the new API.  The only sort-of-legit use case I can think of is mounting more than one btrfs subvolume. But even that should probably not be done by asking the kernel to separately instantiate the filesystem.


May I politely suggest the esteemed participants of that conversation
to RTFS?  Yes, I know that it's less fun that talking about your
rather vague ideas of how the things (surely) work, but it just might
avoid the feats of idiocy like the above.

Andy, I don't know how to put it more plainly: read the fucking source.
Even grep would do.  The same NFS you've granted (among the "handful"
of filesystems) an exception, *DOES* *CALL* *THE* *FUCKING* sget().

Yes, really.  And in some obscure[1] cases (including the one mentioned
upthread) it does reuse a pre-existing superblock.  For a very good
reason.

[1] such as, oh, mounting two filesystems from the same server with
default options - who would've ever thought of doing something so
perverted?

  reply	other threads:[~2018-08-11 22:53 UTC|newest]

Thread overview: 116+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-01 15:23 [PATCH 00/33] VFS: Introduce filesystem context [ver #11] David Howells
2018-08-01 15:24 ` [PATCH 01/33] vfs: syscall: Add open_tree(2) to reference or clone a mount " David Howells
2018-08-02 17:31   ` Alan Jenkins
2018-08-02 21:29     ` Al Viro
2018-08-02 21:51   ` David Howells
2018-08-02 23:46     ` Alan Jenkins
2018-08-01 15:24 ` [PATCH 02/33] vfs: syscall: Add move_mount(2) to move mounts around " David Howells
2018-08-01 15:24 ` [PATCH 03/33] teach move_mount(2) to work with OPEN_TREE_CLONE " David Howells
2018-10-12 14:25   ` Alan Jenkins
2018-08-01 15:24 ` [PATCH 04/33] vfs: Suppress MS_* flag defs within the kernel unless explicitly enabled " David Howells
2018-08-01 15:24 ` [PATCH 05/33] vfs: Introduce the basic header for the new mount API's filesystem context " David Howells
2018-08-01 15:24 ` [PATCH 06/33] vfs: Introduce logging functions " David Howells
2018-08-01 15:24 ` [PATCH 07/33] vfs: Add configuration parser helpers " David Howells
2018-08-01 15:24 ` [PATCH 08/33] vfs: Add LSM hooks for the new mount API " David Howells
2018-08-01 20:50   ` James Morris
2018-08-01 22:53   ` David Howells
2018-08-01 15:25 ` [PATCH 09/33] selinux: Implement the new mount API LSM hooks " David Howells
2018-08-01 15:25 ` [PATCH 10/33] smack: Implement filesystem context security " David Howells
2018-08-01 15:25 ` [PATCH 11/33] apparmor: Implement security hooks for the new mount API " David Howells
2018-08-01 15:25 ` [PATCH 12/33] tomoyo: " David Howells
2018-08-01 15:25 ` [PATCH 13/33] vfs: Separate changing mount flags full remount " David Howells
2018-08-01 15:25 ` [PATCH 14/33] vfs: Implement a filesystem superblock creation/configuration context " David Howells
2018-09-11 17:46   ` Guenter Roeck
2018-09-11 21:52   ` David Howells
2018-09-11 22:07     ` Guenter Roeck
2018-09-11 23:17     ` David Howells
2018-09-11 23:54       ` Guenter Roeck
2018-09-18  9:07         ` Sergey Senozhatsky
2018-09-18  9:40           ` Sergey Senozhatsky
2018-09-18 14:06           ` Guenter Roeck
2018-09-19  1:12             ` Sergey Senozhatsky
2018-09-19  1:26               ` Sergey Senozhatsky
2018-09-18 15:34         ` David Howells
2018-09-18 16:39         ` David Howells
2018-09-19  1:15           ` Sergey Senozhatsky
2018-09-18 17:43         ` David Howells
2018-09-18  9:54   ` Sergey Senozhatsky
2018-09-18 15:28   ` David Howells
2018-08-01 15:25 ` [PATCH 15/33] vfs: Remove unused code after filesystem context changes " David Howells
2018-08-01 15:25 ` [PATCH 16/33] procfs: Move proc_fill_super() to fs/proc/root.c " David Howells
2018-08-01 15:26 ` [PATCH 17/33] proc: Add fs_context support to procfs " David Howells
2018-08-01 15:26 ` [PATCH 18/33] ipc: Convert mqueue fs to fs_context " David Howells
2018-08-01 15:26 ` [PATCH 19/33] cpuset: Use " David Howells
2018-08-01 15:26 ` [PATCH 20/33] kernfs, sysfs, cgroup, intel_rdt: Support " David Howells
2018-08-01 15:26 ` [PATCH 21/33] hugetlbfs: Convert to " David Howells
2018-08-01 15:26 ` [PATCH 22/33] vfs: Remove kern_mount_data() " David Howells
2018-08-01 15:26 ` [PATCH 23/33] vfs: Provide documentation for new mount API " David Howells
2018-08-01 15:26 ` [PATCH 24/33] Make anon_inodes unconditional " David Howells
2018-08-01 15:26 ` [PATCH 25/33] vfs: syscall: Add fsopen() to prepare for superblock creation " David Howells
2018-08-01 15:27 ` [PATCH 26/33] vfs: Implement logging through fs_context " David Howells
2018-08-01 15:27 ` [PATCH 27/33] vfs: Add some logging to the core users of the fs_context log " David Howells
2018-08-01 15:27 ` [PATCH 28/33] vfs: syscall: Add fsconfig() for configuring and managing a context " David Howells
2018-08-06 17:28   ` Eric W. Biederman
2018-08-09 14:14   ` David Howells
2018-08-09 14:24   ` David Howells
2018-08-09 14:35     ` Miklos Szeredi
2018-08-09 15:32     ` Eric W. Biederman
2018-08-09 16:33     ` David Howells
2018-08-11 20:20     ` David Howells
2018-08-11 23:26       ` Andy Lutomirski
2018-08-01 15:27 ` [PATCH 29/33] vfs: syscall: Add fsmount() to create a mount for a superblock " David Howells
2018-08-01 15:27 ` [PATCH 30/33] vfs: syscall: Add fspick() to select a superblock for reconfiguration " David Howells
2018-08-24 14:51   ` Miklos Szeredi
2018-08-24 14:54     ` Andy Lutomirski
2018-08-01 15:27 ` [PATCH 31/33] afs: Add fs_context support " David Howells
2018-08-01 15:27 ` [PATCH 32/33] afs: Use fs_context to pass parameters over automount " David Howells
2018-08-01 15:27 ` [PATCH 33/33] vfs: Add a sample program for the new mount API " David Howells
2018-08-10 14:05 ` BUG: Mount ignores mount options Eric W. Biederman
2018-08-10 14:36   ` Andy Lutomirski
2018-08-10 15:17     ` Eric W. Biederman
2018-08-10 15:24     ` Al Viro
2018-08-10 15:11   ` Tetsuo Handa
2018-08-10 15:13   ` David Howells
2018-08-10 15:16   ` Al Viro
2018-08-11  1:05     ` Eric W. Biederman
2018-08-11  1:46       ` Theodore Y. Ts'o
2018-08-11  4:48         ` Eric W. Biederman
2018-08-11 17:47           ` Casey Schaufler
2018-08-15  4:03             ` Eric W. Biederman
2018-08-11  1:58       ` Al Viro
2018-08-11  2:17         ` Al Viro
2018-08-11  4:43           ` Eric W. Biederman
2018-08-13 12:54         ` Miklos Szeredi
2018-08-10 15:11 ` David Howells
2018-08-10 15:39   ` Theodore Y. Ts'o
2018-08-10 15:55     ` Casey Schaufler
2018-08-10 16:11     ` David Howells
2018-08-10 18:00     ` Eric W. Biederman
2018-08-10 15:53   ` David Howells
2018-08-10 16:14     ` Theodore Y. Ts'o
2018-08-10 20:06       ` Andy Lutomirski
2018-08-10 20:46         ` Theodore Y. Ts'o
2018-08-10 22:12           ` Darrick J. Wong
2018-08-10 23:54             ` Theodore Y. Ts'o
2018-08-11  0:38               ` Darrick J. Wong
2018-08-11  1:32                 ` Eric W. Biederman
2018-08-13 16:35         ` Alan Cox
2018-08-13 16:48           ` Andy Lutomirski
2018-08-13 17:29             ` Al Viro
2018-08-13 19:00               ` James Morris
2018-08-13 19:20                 ` Casey Schaufler
2018-08-15 23:29                 ` Serge E. Hallyn
2018-08-11  0:28       ` Eric W. Biederman
2018-08-11  1:19   ` Eric W. Biederman
2018-08-11  7:29   ` David Howells
2018-08-11 16:31     ` Andy Lutomirski
2018-08-11 16:51       ` Al Viro [this message]
2018-08-15 16:31 ` Should we split the network filesystem setup into two phases? David Howells
2018-08-15 16:51   ` Andy Lutomirski
2018-08-16  3:51   ` Steve French
2018-08-16  5:06   ` Eric W. Biederman
2018-08-16 16:24     ` Steve French
2018-08-16 17:21       ` Eric W. Biederman
2018-08-16 17:23       ` Aurélien Aptel
2018-08-16 18:36         ` Steve French
2018-08-17 23:11     ` Al Viro

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180811165123.GH6515@ZenIV.linux.org.uk \
    --to=viro@zeniv.linux.org.uk \
    --cc=apparmor@lists.ubuntu.com \
    --cc=casey@schaufler-ca.com \
    --cc=cgroups@vger.kernel.org \
    --cc=dhowells@redhat.com \
    --cc=ebiederm@xmission.com \
    --cc=ebiggers@google.com \
    --cc=fenghua.yu@intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hannes@cmpxchg.org \
    --cc=john.johansen@canonical.com \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=lizefan@huawei.com \
    --cc=luto@amacapital.net \
    --cc=miklos@szeredi.hu \
    --cc=paul@paul-moore.com \
    --cc=penguin-kernel@I-love.SAKURA.ne.jp \
    --cc=sds@tycho.nsa.gov \
    --cc=selinux@tycho.nsa.gov \
    --cc=tj@kernel.org \
    --cc=tomoyo-dev-en@lists.sourceforge.jp \
    --cc=torvalds@linux-foundation.org \
    --cc=tytso@mit.edu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).