From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <stable-owner@vger.kernel.org>
Received: from mail.linuxfoundation.org ([140.211.169.12]:34564 "EHLO
        mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1751268AbdHDT5Y (ORCPT
        <rfc822;stable@vger.kernel.org>); Fri, 4 Aug 2017 15:57:24 -0400
Date: Fri, 4 Aug 2017 12:57:22 -0700
From: Greg KH <gregkh@linuxfoundation.org>
To: Juergen Gross <jgross@suse.com>
Cc: stable@vger.kernel.org,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [Patch-for-4.4] xen/blkback: don't use xen_blkif_get() in
 xen-blkback kthread
Message-ID: <20170804195722.GF3477@kroah.com>
References: <20170802092745.18907-1-jgross@suse.com>
 <20170802092745.18907-2-jgross@suse.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20170802092745.18907-2-jgross@suse.com>
Sender: stable-owner@vger.kernel.org
List-ID: <stable.vger.kernel.org>

On Wed, Aug 02, 2017 at 11:27:45AM +0200, Juergen Gross wrote:
> There is no need to use xen_blkif_get()/xen_blkif_put() in the kthread
> of xen-blkback. Thread stopping is synchronous and using the blkif
> reference counting in the kthread will avoid to ever let the reference
> count drop to zero at the end of an I/O running concurrent to
> disconnecting.
> 
> Setting ring->xenblkd to NULL after stopping the kthread isn't needed
> as the kthread does this already.
> 
> Signed-off-by: Juergen Gross <jgross@suse.com>
> Tested-by: Steven Haigh <netwiz@crc.id.au>
> Acked-by: Roger Pau Monn� <roger.pau@citrix.com>
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
> This is a backport of commit a24fa22ce22ae302b3bf8f7008896d52d5d57b8d
> for linux-4.4.y branch.

Both patches now applied, thanks.

greg k-h