Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755939AbdGCOLA (ORCPT ); Mon, 3 Jul 2017 10:11:00 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:37830 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933223AbdGCNq2 (ORCPT ); Mon, 3 Jul 2017 09:46:28 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , Doug Ledford Subject: [PATCH 4.9 164/172] infiniband: hns: avoid gcc-7.0.1 warning for uninitialized data Date: Mon, 3 Jul 2017 15:35:44 +0200 Message-Id: <20170703133422.030245258@linuxfoundation.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170703133414.260777365@linuxfoundation.org> References: <20170703133414.260777365@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1646 Lines: 43 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann commit 5b0ff9a00755d4d9c209033a77f1ed8f3186fe5c upstream. hns_roce_v1_cq_set_ci() calls roce_set_bit() on an uninitialized field, which will then change only a few of its bits, causing a warning with the latest gcc: infiniband/hw/hns/hns_roce_hw_v1.c: In function 'hns_roce_v1_cq_set_ci': infiniband/hw/hns/hns_roce_hw_v1.c:1854:23: error: 'doorbell[1]' is used uninitialized in this function [-Werror=uninitialized] roce_set_bit(doorbell[1], ROCEE_DB_OTHERS_H_ROCEE_DB_OTH_HW_SYNS_S, 1); The code is actually correct since we always set all bits of the port_vlan field, but gcc correctly points out that the first access does contain uninitialized data. This initializes the field to zero first before setting the individual bits. Fixes: 9a4435375cd1 ("IB/hns: Add driver files for hns RoCE driver") Signed-off-by: Arnd Bergmann Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/hns/hns_roce_hw_v1.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c @@ -1267,6 +1267,7 @@ void hns_roce_v1_cq_set_ci(struct hns_ro u32 doorbell[2]; doorbell[0] = cons_index & ((hr_cq->cq_depth << 1) - 1); + doorbell[1] = 0; roce_set_bit(doorbell[1], ROCEE_DB_OTHERS_H_ROCEE_DB_OTH_HW_SYNS_S, 1); roce_set_field(doorbell[1], ROCEE_DB_OTHERS_H_ROCEE_DB_OTH_CMD_M, ROCEE_DB_OTHERS_H_ROCEE_DB_OTH_CMD_S, 3);