From patchwork Tue Jun 12 03:46:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhouyang Jia X-Patchwork-Id: 10459213 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DCA1D60348 for ; Tue, 12 Jun 2018 03:46:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D0ACC28628 for ; Tue, 12 Jun 2018 03:46:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C338B2863E; Tue, 12 Jun 2018 03:46:44 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 44EE128628 for ; Tue, 12 Jun 2018 03:46:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933152AbeFLDqc (ORCPT ); Mon, 11 Jun 2018 23:46:32 -0400 Received: from mail-pl0-f68.google.com ([209.85.160.68]:34438 "EHLO mail-pl0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932460AbeFLDqb (ORCPT ); Mon, 11 Jun 2018 23:46:31 -0400 Received: by mail-pl0-f68.google.com with SMTP id g20-v6so13559066plq.1; Mon, 11 Jun 2018 20:46:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=x7I56ELwwevdipu2gQ2jZ0MqSh/U5Nq/u+3Tv6XMrIk=; b=ZGBI6MhUSCmN4U9KPF8qhYDTKjTpYoa7XYk6mp7oztHY8iuU3Ol1qW44ttGeI6XQX3 hDW1H3Jef5vL0A84cVZmLbyO5rU4DIdWxXA8gUZRS+nDQtcH7e4aeGJw5XRGfhER7T47 fnWvDdUeEtQI8DI1g74Fh0ZOytNtXJzRLPrzcjVK4S/jhD7MX579uMmLGUaGbIyEr1mF ZkX9C0HcDclUkKuv0UZxJM0ux96tbV1udAEXh+inXygsaaoAnslimWNeFOrn2E+9NBG3 J09U2J6YezxM3AlD0+Qr+pjTjjMxbIK3W1a/uSg9z7OGQ7mWtc9kTf3CIm4PJHCkQF+l MaiA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=x7I56ELwwevdipu2gQ2jZ0MqSh/U5Nq/u+3Tv6XMrIk=; b=Y8ZsLaC8s/mYYH+tvZ+NgKeU9JygUm8rYvgGev/j+60C36ufGxb8e59EZwqcm37HQS fwUsJFiZDLuTkGrp/A6jV2gtSExaGIcmCAzsW4P1Rk0+8AnXVQbSXsHk8F88jI4hLhD0 DfC7IPcLN1hWOTO6fJ3kcO0i3m6DtWcefDxXgIUQT1/a2VysyELceqnZMbM4Y3GXt8hN GfNR5hH6NkSFIMbkXWYqV2D2StNhI0kaX9f+0h2zNW/hFd9/v4xhN/XG1jFm5nXyMPcg E8meCBJJi1L2csU9Td7W2eeJV3cKynbI/iwZUaPpc6RaRTsb5upWRcCTcHy7BfAWQ0bj u7Qg== X-Gm-Message-State: APt69E2vQNW+91kqtf5ZcgbNHXVVkvv8ll/6WNmzGfP64eAc56Kh4jl7 M202Y1cu0VtkJONluQIV1zg= X-Google-Smtp-Source: ADUXVKJ0+LEa3Nlb+k6vom7aLjEeNImsenJoJopAwRPFjbrQaxX/qrv6IlckdoUiECxQqUYN879/UQ== X-Received: by 2002:a17:902:b611:: with SMTP id b17-v6mr2069734pls.284.1528775191021; Mon, 11 Jun 2018 20:46:31 -0700 (PDT) Received: from localhost ([103.88.46.82]) by smtp.gmail.com with ESMTPSA id e189-v6sm33100393pfc.134.2018.06.11.20.46.29 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 11 Jun 2018 20:46:30 -0700 (PDT) From: Zhouyang Jia Cc: Zhouyang Jia , Juergen Gross , Boris Ostrovsky , xen-devel@lists.xenproject.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] xen/scsiback: add error handling for xenbus_printf Date: Tue, 12 Jun 2018 11:46:25 +0800 Message-Id: <1528775185-39467-1-git-send-email-jiazhouyang09@gmail.com> X-Mailer: git-send-email 2.7.4 To: unlisted-recipients:; (no To-header on input) Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When xenbus_printf fails, the lack of error-handling code may cause unexpected results. This patch adds error-handling code after calling xenbus_printf. Signed-off-by: Zhouyang Jia --- drivers/xen/xen-scsiback.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c index 7bc88fd..13ab54c 100644 --- a/drivers/xen/xen-scsiback.c +++ b/drivers/xen/xen-scsiback.c @@ -1027,8 +1027,9 @@ static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state, scsiback_del_translation_entry(info, vir); } } else if (!try) { - xenbus_printf(XBT_NIL, info->dev->nodename, state, - "%d", XenbusStateClosed); + if (xenbus_printf(XBT_NIL, info->dev->nodename, state, + "%d", XenbusStateClosed)) + pr_err("xenbus_printf error %s\n", state); } } @@ -1067,8 +1068,9 @@ static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op, snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent); val = xenbus_read(XBT_NIL, dev->nodename, str, NULL); if (IS_ERR(val)) { - xenbus_printf(XBT_NIL, dev->nodename, state, - "%d", XenbusStateClosed); + if (xenbus_printf(XBT_NIL, dev->nodename, state, + "%d", XenbusStateClosed)) + pr_err("xenbus_printf error %s\n", state); return; } strlcpy(phy, val, VSCSI_NAMELEN); @@ -1079,8 +1081,9 @@ static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op, err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u", &vir.hst, &vir.chn, &vir.tgt, &vir.lun); if (XENBUS_EXIST_ERR(err)) { - xenbus_printf(XBT_NIL, dev->nodename, state, - "%d", XenbusStateClosed); + if (xenbus_printf(XBT_NIL, dev->nodename, state, + "%d", XenbusStateClosed)) + pr_err("xenbus_printf error %s\n", state); return; }