From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09884C54E8D for ; Tue, 12 May 2020 04:24:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2A4A20733 for ; Tue, 12 May 2020 04:24:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728288AbgELEYX (ORCPT ); Tue, 12 May 2020 00:24:23 -0400 Received: from mx2.suse.de ([195.135.220.15]:50014 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725816AbgELEYW (ORCPT ); Tue, 12 May 2020 00:24:22 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id A3E99AEDF; Tue, 12 May 2020 04:24:23 +0000 (UTC) Subject: Re: [PATCH] xen/pvcalls-back: test for errors when calling backend_connect() To: Stefano Stabellini Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, Boris Ostrovsky , stable@vger.kernel.org References: <20200511074231.19794-1-jgross@suse.com> From: =?UTF-8?B?SsO8cmdlbiBHcm/Dnw==?= Message-ID: <17512c98-b309-7b83-8c9c-cc8d43a495a2@suse.com> Date: Tue, 12 May 2020 06:24:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11.05.20 23:41, Stefano Stabellini wrote: > On Mon, 11 May 2020, Juergen Gross wrote: >> backend_connect() can fail, so switch the device to connected only if >> no error occurred. >> >> Fixes: 0a9c75c2c7258f2 ("xen/pvcalls: xenbus state handling") >> Cc: stable@vger.kernel.org >> Signed-off-by: Juergen Gross > > Reviewed-by: Stefano Stabellini > > >> --- >> drivers/xen/pvcalls-back.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c >> index cf4ce3e9358d..41a18ece029a 100644 >> --- a/drivers/xen/pvcalls-back.c >> +++ b/drivers/xen/pvcalls-back.c >> @@ -1088,7 +1088,8 @@ static void set_backend_state(struct xenbus_device *dev, >> case XenbusStateInitialised: >> switch (state) { >> case XenbusStateConnected: >> - backend_connect(dev); >> + if (backend_connect(dev)) >> + return; > > Do you think it would make sense to WARN? There already should be an error message (either due to a failed grant mapping or a failed memory allocation). Juergen