From: Al Viro <viro@zeniv.linux.org.uk>
To: NeilBrown <neil@brown.name>
Cc: Miklos Szeredi <miklos@szeredi.hu>,
Amir Goldstein <amir73il@gmail.com>, Kees Cook <kees@kernel.org>,
Joel Granados <joel.granados@kernel.org>,
Richard Weinberger <richard@nod.at>,
Anton Ivanov <anton.ivanov@cambridgegreys.com>,
Johannes Berg <johannes@sipsolutions.net>,
Breno Leitao <leitao@debian.org>,
Andreas Hindborg <a.hindborg@kernel.org>,
Jan Harkes <jaharkes@cs.cmu.edu>, Hugh Dickins <hughd@google.com>,
Baolin Wang <baolin.wang@linux.alibaba.com>,
Namjae Jeon <linkinjeon@kernel.org>,
Hyunchul Lee <hyc.lee@gmail.com>,
Carlos Maiolino <cem@kernel.org>,
Christian Brauner <brauner@kernel.org>,
Jeff Layton <jlayton@kernel.org>, Jan Kara <jack@suse.cz>,
linux-fsdevel@vger.kernel.org, fuse-devel@lists.linux.dev,
linux-kernel@vger.kernel.org, linux-unionfs@vger.kernel.org,
linux-um@lists.infradead.org, codalist@coda.cs.cmu.edu,
coda@cs.cmu.edu, linux-mm@kvack.org, ntfs@lists.linux.dev,
linux-xfs@vger.kernel.org
Subject: Re: [PATCH 4/7] configfs: remove d_add() calls before configfs_attach_group()
Date: Tue, 29 Sep 2026 06:07:39 +0100 [thread overview]
Message-ID: <20260929050739.GB3909609@ZenIV> (raw)
In-Reply-To: <20260929034158.1455429-5-neilb@ownmail.net>
On Tue, Sep 29, 2026 at 01:36:04PM +1000, NeilBrown wrote:
> From: NeilBrown <neil@brown.name>
>
> These d_add() calls cannot be necessary. The inode given is NULL so all
> they do is attach the dentry to the hash table.
>
> If configfs_attach_group() fails, then d_drop() is called so the dentry
> will be detached.
> If configfs_attach_group() succeeds, then
> configfs_attach_group -> configfs_attach_item ->configfs_create_dir
> must have succeeded, so d_instantiate() will have been called and the
> dentry hashed there.
Neither in mainline, nor in -next...
d_add() _is_ wrong there, but this is not the right solution. What
we really ought to do is build the subtree first, then either dissolve
it (without any pathname resolution having ever seen it) or move it
in place once we are sure that everything worked.
next prev parent reply other threads:[~2026-09-29 5:07 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-29 3:36 [PATCH 0/7] multiple-filesystems: prepare for changes to VFS locking NeilBrown
2026-09-29 3:36 ` [PATCH 1/7] VFS/xfs/ntfs: drop parent lock across d_alloc_parallel() in d_add_ci() NeilBrown
2026-09-29 3:36 ` [PATCH 2/7] shmem: use d_duplicate() NeilBrown
2026-09-29 3:36 ` [PATCH 3/7] coda: don't d_drop() early NeilBrown
2026-09-29 3:36 ` [PATCH 4/7] configfs: remove d_add() calls before configfs_attach_group() NeilBrown
2026-09-29 5:07 ` Al Viro [this message]
2026-10-01 1:32 ` NeilBrown
2026-09-29 3:36 ` [PATCH 5/7] hostfs: don't d_drop() before d_splice_alias() in hostfs_mkdir() NeilBrown
2026-09-29 3:36 ` [PATCH 6/7] procfs: drop parent lock for d_alloc_parallel() in iterate_shared() NeilBrown
2026-09-29 3:36 ` [PATCH 7/7] ovl: stop using lookup_one() in ovl_iterate() NeilBrown
2026-09-30 13:35 ` Amir Goldstein
2026-09-30 21:43 ` NeilBrown
2026-09-30 10:22 ` [syzbot ci] Re: multiple-filesystems: prepare for changes to VFS locking syzbot ci
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=20260929050739.GB3909609@ZenIV \
--to=viro@zeniv.linux.org.uk \
--cc=a.hindborg@kernel.org \
--cc=amir73il@gmail.com \
--cc=anton.ivanov@cambridgegreys.com \
--cc=baolin.wang@linux.alibaba.com \
--cc=brauner@kernel.org \
--cc=cem@kernel.org \
--cc=coda@cs.cmu.edu \
--cc=codalist@coda.cs.cmu.edu \
--cc=fuse-devel@lists.linux.dev \
--cc=hughd@google.com \
--cc=hyc.lee@gmail.com \
--cc=jack@suse.cz \
--cc=jaharkes@cs.cmu.edu \
--cc=jlayton@kernel.org \
--cc=joel.granados@kernel.org \
--cc=johannes@sipsolutions.net \
--cc=kees@kernel.org \
--cc=leitao@debian.org \
--cc=linkinjeon@kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-um@lists.infradead.org \
--cc=linux-unionfs@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=miklos@szeredi.hu \
--cc=neil@brown.name \
--cc=ntfs@lists.linux.dev \
--cc=richard@nod.at \
/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
all inboxes | Powered by JetHome®