From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755737AbcG0J3Q (ORCPT ); Wed, 27 Jul 2016 05:29:16 -0400 Received: from smtp.ctxuk.citrix.com ([185.25.65.24]:19958 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754356AbcG0J3K (ORCPT ); Wed, 27 Jul 2016 05:29:10 -0400 X-IronPort-AV: E=Sophos;i="5.28,429,1464652800"; d="scan'208";a="27256315" From: Paul Durrant To: Bob Liu , Roger Pau Monne CC: "xen-devel@lists.xenproject.org" , "linux-kernel@vger.kernel.org" Subject: RE: [Xen-devel] [PATCH v3] xen-blkfront: dynamic configuration of per-vbd resources Thread-Topic: [Xen-devel] [PATCH v3] xen-blkfront: dynamic configuration of per-vbd resources Thread-Index: AQHR5+dyLf8YenMou025wPO72U7vxaAsAnzA Date: Wed, 27 Jul 2016 09:29:08 +0000 Message-ID: <32978d4e198f4359bc7878d8474b3078@AMSPEX02CL03.citrite.net> References: <1469589685-31630-1-git-send-email-bob.liu@oracle.com> <20160727080729.7sgmqak42rw6vaok@mac> <57987AF6.1050105@oracle.com> In-Reply-To: <57987AF6.1050105@oracle.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 X-DLP: AMS1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id u6R9TKpe027369 > -----Original Message----- [snip] > > > > Also, I'm not sure this is correct, if blkfront sees the "Closing" state on > > blkback it will try to close the frontend and destroy the block device (see > > blkfront_closing), and this should be avoided. You should call > > blkfront_resume as soon as you see the backend move to the Closed or > Closing > > states, without calling blkfront_closing. > > > > I didn't get how this can happen, backend state won't be changed to 'Closing' > before blkfront_closing() is called. > So I think current logic is fine. > Backends can go to closing before frontends, when the PV device is being detached. Paul