From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [HACK] fs/super.c: sync ro remount after blocking writers
Date: Mon, 3 Feb 2014 02:23:03 -0800
Message-ID: <20140203102303.GB11829@infradead.org>
References: <1391095614-21554-1-git-send-email-andrew.ruder@elecsyscorp.com>
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Cc: linux-fsdevel@vger.kernel.org, linux-mtd@lists.infradead.org,
	Artem Bityutskiy <dedekind1@gmail.com>,
	Christoph Hellwig <hch@infradead.org>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Richard Weinberger <richard@nod.at>
To: Andrew Ruder <andrew.ruder@elecsyscorp.com>
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On Thu, Jan 30, 2014 at 09:26:54AM -0600, Andrew Ruder wrote:
> 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.

>>From the link that Richard posted it seems like you have a testcase.
Can you please integrate it into xfstests so that we can properly
regression test for this issue from now on?