Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933149AbbBCEfy (ORCPT ); Mon, 2 Feb 2015 23:35:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33866 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753862AbbBCEfx (ORCPT ); Mon, 2 Feb 2015 23:35:53 -0500 Date: Tue, 03 Feb 2015 04:43:28 +0008 From: Jason Wang Subject: RE: [PATCH v2 1/3] hv: hv_util: move vmbus_open() to a later place To: KY Srinivasan Cc: Dexuan Cui , "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "driverdev-devel@linuxdriverproject.org" , "olaf@aepfle.de" , "apw@canonical.com" , "vkuznets@redhat.com" , Haiyang Zhang Message-Id: <1422938128.6732.3@smtp.corp.redhat.com> In-Reply-To: References: <1422851718-2353-1-git-send-email-decui@microsoft.com> <1422869774.7028.5@smtp.corp.redhat.com> <1422932926.6732.0@smtp.corp.redhat.com> <1422934695.6732.2@smtp.corp.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3683 Lines: 109 On Tue, Feb 3, 2015 at 11:40 AM, KY Srinivasan wrote: > > >> -----Original Message----- >> From: Jason Wang [mailto:jasowang@redhat.com] >> Sent: Monday, February 2, 2015 7:38 PM >> To: KY Srinivasan >> Cc: Dexuan Cui; gregkh@linuxfoundation.org; >> linux-kernel@vger.kernel.org; >> driverdev-devel@linuxdriverproject.org; olaf@aepfle.de; >> apw@canonical.com; vkuznets@redhat.com; Haiyang Zhang >> Subject: RE: [PATCH v2 1/3] hv: hv_util: move vmbus_open() to a >> later place >> >> >> >> On Tue, Feb 3, 2015 at 11:30 AM, KY Srinivasan >> wrote: >> > >> > >> >> -----Original Message----- >> >> From: Jason Wang [mailto:jasowang@redhat.com] >> >> Sent: Monday, February 2, 2015 7:09 PM >> >> To: Dexuan Cui >> >> Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; >> >> driverdev- >> >> devel@linuxdriverproject.org; olaf@aepfle.de; >> apw@canonical.com; KY >> >> Srinivasan; vkuznets@redhat.com; Haiyang Zhang >> >> Subject: RE: [PATCH v2 1/3] hv: hv_util: move vmbus_open() to a >> >> later place >> >> >> >> >> >> >> >> On Mon, Feb 2, 2015 at 6:09 PM, Dexuan Cui >> >> wrote: >> >> >> -----Original Message----- >> >> >> From: Jason Wang [mailto:jasowang@redhat.com] >> Sent: >> Monday, >> >> February 2, 2015 17:36 PM >> To: Dexuan Cui >> Cc: >> >> gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; >> >> >> driverdev- >> devel@linuxdriverproject.org; olaf@aepfle.de; >> >> apw@canonical.com; KY >> Srinivasan; vkuznets@redhat.com; >> Haiyang >> >> Zhang >> Subject: Re: [PATCH v2 1/3] hv: hv_util: move >> vmbus_open() >> >> to a >> later place >> >> >> >> On Mon, Feb 2, 2015 at >> 12:35 >> >> PM, Dexuan Cui >> wrote: >> >> >> > Before the line vmbus_open() returns, srv->util_cb can be >> >> already >> > running > and the variables, like >> util_fw_version, are >> >> needed by >> the > srv->util_cb. >> >> >> >> >> >> A questions is why we do this for util only? Can callbacks >> of >> >> other >> devices be called before vmbus_open() returns? >> >> > The variables are used in vmbus_prep_negotiate_resp(), which >> is >> >> only > for the util devices. >> >> > >> >> > I think the other devices should already handle the similar >> issue >> >> > properly. >> >> > If this is not the case, we need to fix them too. >> >> >> >> Better to check all the others, e.g in balloon_probe(), it call >> >> hv_set_drvdata() after vmbus_open() and dose several datas >> setups in >> >> the middle. If balloon_onchannelcallback() could be called >> before >> >> hv_set_drvdata(), the code looks wrong. >> > >> > Jason, >> > >> > For all other device types, the guest initiates the communication >> with >> > the host and potentially negotiates appropriate (supported) >> version >> > with the host. For the services packaged in the util driver, the >> flow >> > is a little different - the host pushes the version information >> into >> > the guest. So, the fix Dexuan made is only needed in the util >> driver. >> > >> > Regards, >> > >> > K. Y >> >> Thanks, so you mean for other device, it won't get any interrupt >> before guest >> negotiate the version with host? > > Yes, the guest initiates the version negotiation. Are you seeing > something different? > > K. Y No, thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/