From: Marco Stornelli <marco.stornelli@gmail.com>
To: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>,
Linux FS Maling List <linux-fsdevel@vger.kernel.org>,
Linux Kernel Maling List <linux-kernel@vger.kernel.org>,
Alexander Stein <alexander.stein@systec-electronic.com>
Subject: Re: [RFC] [PATCH] vfs: remount all file-systems R/O on emergency remount.
Date: Fri, 24 Aug 2012 15:20:39 +0200 [thread overview]
Message-ID: <50377FA7.50708@gmail.com> (raw)
In-Reply-To: <1345793166-14230-1-git-send-email-dedekind1@gmail.com>
Il 24/08/2012 09:26, Artem Bityutskiy ha scritto:
> From: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
>
> Currently the emergency remount (triggered by Sysrq-u) re-mounting only
> those file-systems R/O, which have an associated block device (sb->s_bdev).
> This does not work for file-systems like UBIFS and JFFS2 which work on top
> of MTD devices (character devices) and always have sb->s_bdev = NULL.
>
> This also does not work for tmpfs.
>
> Most probably the intention was to avoid re-mounting R/O file-systems like
> procfs, sysfs, cgroup, and debugfs. However, I do not really see why not
> to remount them R/O as well in case of emergency.
>
> This patch removes the 'sb->s_bdev != NULL' check from
> 'do_emergency_remount()', so _all_ file-systems will be re-mounted R/O.
>
> Tested in Fedora - all file-systems (ext4, ubifs, procfs, sysfs, cgroup, and
> debugfs) become R/O on Sysrq-u with this patch.
>
> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Does it make sense to remount r/o for example debugfs in this case?
Maybe if there is something wrong I want enable something to catch debug
info. Similar things for other pseudo-fs. Sure, the s_bdev seems a
strong check. We could add a new flag to know if the emergency remount
should be happen. It would give us the fs granularity, and maybe it
could be turned on/off with the mount.
Marco
next prev parent reply other threads:[~2012-08-24 13:20 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-24 7:26 [RFC] [PATCH] vfs: remount all file-systems R/O on emergency remount Artem Bityutskiy
2012-08-24 13:20 ` Marco Stornelli [this message]
2012-08-24 13:38 ` Artem Bityutskiy
2012-08-24 13:51 ` Marco Stornelli
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