From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Weinberger <richard@nod.at>
Subject: Re: [HACK] fs/super.c: sync ro remount after blocking writers
Date: Fri, 31 Jan 2014 09:20:30 +0100
Message-ID: <52EB5CCE.5080609@nod.at>
References: <1391095614-21554-1-git-send-email-andrew.ruder@elecsyscorp.com>
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Cc: Artem Bityutskiy <dedekind1@gmail.com>,
	Christoph Hellwig <hch@infradead.org>,
	Alexander Viro <viro@zeniv.linux.org.uk>
To: Andrew Ruder <andrew.ruder@elecsyscorp.com>,
	linux-fsdevel@vger.kernel.org, linux-mtd@lists.infradead.org
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Am 30.01.2014 16:26, schrieb Andrew Ruder:
> Move sync_filesystem() after sb_prepare_remount_readonly().  If writers
> sneak in anywhere from sync_filesystem() to sb_prepare_remount_readonly()
> it can cause inodes to be dirtied and writeback to occur well after
> sys_mount() has completely successfully.
> 
> This was spotted by corrupted ubifs filesystems on reboot, but appears
> that it can cause issues with any filesystem using writeback.

Link to original report:
http://lists.infradead.org/pipermail/linux-mtd/2014-January/051651.html

What we see is that writeback still happens after mounting the fs ro.

Thanks,
//richard