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Date:   Mon, 24 Jan 2022 15:14:34 +0000
From:   Alasdair G Kergon <agk@redhat.com>
To:     Brian Geffon <bgeffon@google.com>
Cc:     Alasdair Kergon <agk@redhat.com>,
        Mike Snitzer <snitzer@redhat.com>, dm-devel@redhat.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] dm: introduce a no open flag for deferred remove
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        Alasdair Kergon <agk@redhat.com>, Mike Snitzer <snitzer@redhat.com>,
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On Mon, Jan 24, 2022 at 07:02:09AM -0800, Brian Geffon wrote:
> When a device is being removed with deferred remove it's
> still possible to open and use the device. This change
> introduces a flag called DM_DEFERRED_REMOVE_NO_OPEN_FLAG
> which when used with DM_DEFERRED_REMOVE will cause any
> new opens to fail with -ENXIO.
 
What is the need for this?
Does it break any semantics assumed by userspace?

Alasdair