From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753851AbaJWIZy (ORCPT ); Thu, 23 Oct 2014 04:25:54 -0400 Received: from xavier.telenet-ops.be ([195.130.132.52]:43751 "EHLO xavier.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753145AbaJWIZw (ORCPT ); Thu, 23 Oct 2014 04:25:52 -0400 From: Geert Uytterhoeven To: "David S. Miller" , Iyappan Subramanian , Keyur Chudgar Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v3] drivers: net: xgene: Rewrite buggy loop in xgene_enet_ecc_init() Date: Thu, 23 Oct 2014 10:25:53 +0200 Message-Id: <1414052753-10183-1-git-send-email-geert@linux-m68k.org> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c: In function ‘xgene_enet_ecc_init’: drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c:126: warning: ‘data’ may be used uninitialized in this function Depending on the arbitrary value on the stack, the loop may terminate too early, and cause a bogus -ENODEV failure. Signed-off-by: Geert Uytterhoeven --- v3: - Use "do { ... } while (...);" instead of "for (...) { ... }", v2: - Rewrite the loop instead of pre-initializing data. drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c b/drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c index e6d24c2101982444..c22f32622fa9a50a 100644 --- a/drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c +++ b/drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c @@ -124,20 +124,18 @@ static int xgene_enet_ecc_init(struct xgene_enet_pdata *p) { struct net_device *ndev = p->ndev; u32 data; - int i; + int i = 0; xgene_enet_wr_diag_csr(p, ENET_CFG_MEM_RAM_SHUTDOWN_ADDR, 0); - for (i = 0; i < 10 && data != ~0U ; i++) { + do { usleep_range(100, 110); data = xgene_enet_rd_diag_csr(p, ENET_BLOCK_MEM_RDY_ADDR); - } + if (data == ~0U) + return 0; + } while (++i < 10); - if (data != ~0U) { - netdev_err(ndev, "Failed to release memory from shutdown\n"); - return -ENODEV; - } - - return 0; + netdev_err(ndev, "Failed to release memory from shutdown\n"); + return -ENODEV; } static void xgene_enet_config_ring_if_assoc(struct xgene_enet_pdata *p) -- 1.9.1