Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 7 Sep 2018 09:23:19 +0200
From:   Valentin Vidic <Valentin.Vidic@CARNet.hr>
To:     Roger Pau =?iso-8859-1?Q?Monn=E9?= <roger.pau@citrix.com>
Cc:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Jens Axboe <axboe@kernel.dk>, xen-devel@lists.xenproject.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org, drbd-user@lists.linbit.com
Message-ID: <20180907072319.GA26705@gavran.carpriv.carnet.hr>
References: <20180829065214.23546-1-Valentin.Vidic@CARNet.hr>
 <20180905103649.edugijsjx4v2fbxd@mac.bytemobile.com>
 <20180905113515.GU26705@gavran.carpriv.carnet.hr>
 <20180905162801.GB26705@gavran.carpriv.carnet.hr>
 <20180906162932.7qge5dmrgyqbmbbj@mac.bytemobile.com>
 <20180906221929.GZ26705@gavran.carpriv.carnet.hr>
 <20180907071530.te5dxdvg4zqgqscj@mac.bytemobile.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20180907071530.te5dxdvg4zqgqscj@mac.bytemobile.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Subject: Re: [PATCH] xen-blkback: Switch to closed state after releasing the
 backing device
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Fri, Sep 07, 2018 at 09:15:30AM +0200, Roger Pau Monn? wrote:
> I'm not sure that's a good idea, there are a lot of backends (apart
> from blkback), and the tools won't know whether a specific backend
> supports such state or not. Also the current protocol and states are
> shared between all the Xen PV devices, so new additions should be
> considered very carefully.

Sure, I understand.

> IMO the best options are either calling vbd_free/vbd_create at proper
> stages in blkback or changing the hotplug script so it waits for the
> device to have no open clients.

Changing the block-drbd script would be ideal for me too, but I don't
think that piece of DRBD state is exposed at the moment.

-- 
Valentin