From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: dm-raid: check for zero feature flags in metadata
Date: Fri, 29 Apr 2016 15:23:46 -0400
Message-ID: <20160429192346.GB22007@redhat.com>
References: <1461949196-17999-1-git-send-email-heinzm@redhat.com>
	<20160429191835.GA22007@redhat.com>
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On Fri, Apr 29 2016 at  3:18pm -0400,
Mike Snitzer <snitzer@redhat.com> wrote:

> On Fri, Apr 29 2016 at 12:59pm -0400,
> heinzm@redhat.com <heinzm@redhat.com> wrote:
> 
> > From: Heinz Mauelshagen <heinzm@redhat.com>
> > 
> > Because we don't support any feature flags in the dm-raid ondisk
> > metadata yet (see struct dm_raid_superblock, 'features' member), 
> > this patch adds a check to ensure no flags are actually set or
> > reject the activation of the RAID mapping.
> > 
> > This is to prevent possible data corruption in case of a
> > kernel downgrade when there'll potentially be feature flags
> > set by a future dm-raid target.
> > 
> > 
> > Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
> 
> merged for 4.7, see:
> https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-4.7&id=480375cd7ea3eed60381539dbfa96851b6174820

Actually, I revised the header and patch content, see:

https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-4.7&id=ecdb57d205b98b656ab3ea0412f7a15ec003357f