From mboxrd@z Thu Jan 1 00:00:00 1970 From: 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> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven To: "David S. Miller" , Iyappan Subramanian , Keyur Chudgar Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c: In function =E2=80=98= xgene_enet_ecc_init=E2=80=99: drivers/net/ethernet/apm/xgene/xgene_enet_sgmac.c:126: warning: =E2=80=98= data=E2=80=99 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/driver= s/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 =3D p->ndev; u32 data; - int i; + int i =3D 0; =20 xgene_enet_wr_diag_csr(p, ENET_CFG_MEM_RAM_SHUTDOWN_ADDR, 0); - for (i =3D 0; i < 10 && data !=3D ~0U ; i++) { + do { usleep_range(100, 110); data =3D xgene_enet_rd_diag_csr(p, ENET_BLOCK_MEM_RDY_ADDR); - } + if (data =3D=3D ~0U) + return 0; + } while (++i < 10); =20 - if (data !=3D ~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; } =20 static void xgene_enet_config_ring_if_assoc(struct xgene_enet_pdata *p= ) --=20 1.9.1