From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: dm-thinp BUG
	at	drivers/md/persistent-data/dm-btree-remove.c:188
Date: Thu, 14 Feb 2013 22:48:11 -0500
Message-ID: <20130215034811.GA10038@redhat.com>
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	<20130215023400.GM24130@agk-dp.fab.redhat.com>
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On Thu, Feb 14 2013 at  9:34pm -0500,
Alasdair G Kergon <agk@redhat.com> wrote:

> On Thu, Feb 14, 2013 at 06:07:56PM -0800, Eric Wheeler wrote:
> > Does this indicate a corrupt volume or metadata volume?
> 
> It could be a software bug.
> It is always worth trying the newest code, but I don't spot any
> obvious change that could be related to this.
...
> The trace shows it's applying a 'discard' to the metadata and releasing
> blocks when the problem occurs.

Right, given that the BUG trace shows active discards it could be that
v3.8 commit e808807 ("dm thin: fix race between simultaneous io and
discards to same block") may help.

(though I never saw that race manifest with the BUG in question)