From: Al Viro <viro@ZenIV.linux.org.uk>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: dave@linux.vnet.ibm.com, akpm@linux-foundation.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 7/9] vfs: protect remounting superblock read-only
Date: Fri, 22 Oct 2010 07:46:27 +0100 [thread overview]
Message-ID: <20101022064627.GA21607@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20101005103144.051231469@szeredi.hu>
On Tue, Oct 05, 2010 at 12:31:15PM +0200, Miklos Szeredi wrote:
> From: Miklos Szeredi <mszeredi@suse.cz>
>
> Currently remouting superblock read-only is racy in a major way.
>
> With the per mount read-only infrastructure it is now possible to
> prevent most races, which this patch attempts.
>
> Before starting the remount read-only, set MNT_WRITE_HOLD on all
> mounts so that writes are held off until the remount either succeeds
> or fails.
Umm... What'll happen if your remount will say mnt_want_write() on
e.g. internal vfsmount over that sb? Or, more subtle, tries to
update atime on some opened struct file on that sb.
next prev parent reply other threads:[~2010-10-22 6:46 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-05 10:31 [PATCH 0/9] read-only remount fixes Miklos Szeredi
2010-10-05 10:31 ` [PATCH 1/9] vfs: fix infinite loop caused by clone_mnt race Miklos Szeredi
2010-10-05 10:49 ` Miklos Szeredi
2010-10-05 10:31 ` [PATCH 2/9] vfs: ignore error on forced remount Miklos Szeredi
2010-10-05 10:31 ` [PATCH 3/9] vfs: fix per mount read-write Miklos Szeredi
2010-10-05 10:31 ` [PATCH 4/9] vfs: add sb_force_remount_readonly() helper Miklos Szeredi
2010-10-05 10:31 ` [PATCH 5/9] vfs: allow mnt_want_write() to sleep Miklos Szeredi
2010-10-05 10:31 ` [PATCH 6/9] vfs: keep list of mounts for each superblock Miklos Szeredi
2010-10-05 10:31 ` [PATCH 7/9] vfs: protect remounting superblock read-only Miklos Szeredi
2010-10-22 6:46 ` Al Viro [this message]
2010-10-22 12:25 ` Miklos Szeredi
2010-10-22 16:10 ` Miklos Szeredi
2010-10-22 16:14 ` [PATCH 7/9 updated] " Miklos Szeredi
2010-10-23 16:19 ` Al Viro
2010-10-23 19:35 ` Miklos Szeredi
2010-10-23 21:42 ` Al Viro
2010-10-25 12:36 ` Miklos Szeredi
2010-10-05 10:31 ` [PATCH 8/9] vfs: fs_may_remount_ro: turn unnecessary check into a WARN_ON Miklos Szeredi
2010-10-05 10:31 ` [PATCH 9/9] vfs: mark mounts read-only on forced remount Miklos Szeredi
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=20101022064627.GA21607@ZenIV.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=akpm@linux-foundation.org \
--cc=dave@linux.vnet.ibm.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=miklos@szeredi.hu \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.