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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 CA806C433E0 for ; Mon, 29 Mar 2021 07:19:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A158761945 for ; Mon, 29 Mar 2021 07:19:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231197AbhC2HTB (ORCPT ); Mon, 29 Mar 2021 03:19:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34740 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229873AbhC2HS6 (ORCPT ); Mon, 29 Mar 2021 03:18:58 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB655C061574 for ; Mon, 29 Mar 2021 00:18:57 -0700 (PDT) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lQmAl-0008RT-Ba; Mon, 29 Mar 2021 09:18:51 +0200 Received: from pengutronix.de (unknown [IPv6:2a03:f580:87bc:d400:44b9:f06e:1c40:69b1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 7C0B7602718; Mon, 29 Mar 2021 06:48:51 +0000 (UTC) Date: Mon, 29 Mar 2021 08:48:50 +0200 From: Marc Kleine-Budde To: kernel test robot Cc: kbuild-all@lists.01.org, clang-built-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: Re: drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c:2267:16: warning: taking address of packed member 'hw_tx_obj' of class or structure 'mcp251xfd_tx_obj_load_buf::(anonymous)' may result in an unaligned pointer value Message-ID: <20210329064850.vh7rlwh7oapjqucj@pengutronix.de> References: <202103271812.xDwl25lD-lkp@intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="llupkarg5grkzwxh" Content-Disposition: inline In-Reply-To: <202103271812.xDwl25lD-lkp@intel.com> X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --llupkarg5grkzwxh Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 27.03.2021 18:16:14, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.gi= t master > head: 0f4498cef9f5cd18d7c6639a2a902ec1edc5be4e > commit: eb79a267c9b3e608e7762a1b221428f37ace3aa3 can: mcp251xfd: rename a= ll remaining occurrence to mcp251xfd > date: 6 months ago > config: mips-randconfig-r035-20210327 (attached as .config) > compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project d50f= e9f0d6b9ee61df8830a67ea0a33c27a637e7) > reproduce (this is a W=3D1 build): > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbi= n/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # install mips cross compiling tool for clang build > # apt-get install binutils-mips-linux-gnu > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.= git/commit/?id=3Deb79a267c9b3e608e7762a1b221428f37ace3aa3 > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/= git/torvalds/linux.git > git fetch --no-tags linus master > git checkout eb79a267c9b3e608e7762a1b221428f37ace3aa3 > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=3D$HOME/0day COMPILER=3Dclang make.cross AR= CH=3Dmips=20 >=20 > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot >=20 > All warnings (new ones prefixed by >>): [...] > >> drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c:2267:16: warning: takin= g address of packed member 'hw_tx_obj' of class or structure 'mcp251xfd_tx_= obj_load_buf::(anonymous)' may result in an unaligned pointer value [-Waddr= ess-of-packed-member] > hw_tx_obj =3D &load_buf->crc.hw_tx_obj; > ^~~~~~~~~~~~~~~~~~~~~~~ > drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c:2269:16: warning: takin= g address of packed member 'hw_tx_obj' of class or structure 'mcp251xfd_tx_= obj_load_buf::(anonymous)' may result in an unaligned pointer value [-Waddr= ess-of-packed-member] > hw_tx_obj =3D &load_buf->nocrc.hw_tx_obj; > ^~~~~~~~~~~~~~~~~~~~~~~~~ > 4 warnings and 1 error generated. That warning is technically correct, hw_tx_obj is an unaligned pointer in the first warning, but... > vim +2267 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c >=20 > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2215 static void > eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine= -Budde 2020-09-30 2216 mcp251xfd_tx_obj_from_skb(const struct mcp251xfd_p= riv *priv, > eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine= -Budde 2020-09-30 2217 struct mcp251xfd_tx_obj *tx_obj, > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2218 const struct sk_buff *skb, > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2219 unsigned int seq) > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2220 { [...] > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2265 load_buf =3D &tx_obj->buf; > eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine= -Budde 2020-09-30 2266 if (priv->devtype_data.quirks & MCP251XFD_QUIRK_C= RC_TX) > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 @2267 hw_tx_obj =3D &load_buf->crc.hw_tx_obj; > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2268 else > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2269 hw_tx_obj =3D &load_buf->nocrc.hw_tx_obj; > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2270 =20 > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2271 put_unaligned_le32(id, &hw_tx_obj->id); > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2272 put_unaligned_le32(flags, &hw_tx_obj->flags); > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2273 =20 > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2274 /* Clear data at end of CAN frame */ > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2275 offset =3D round_down(cfd->len, sizeof(u32)); > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2276 len =3D round_up(can_dlc2len(dlc), sizeof(u32)) -= offset; > eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine= -Budde 2020-09-30 2277 if (MCP251XFD_SANITIZE_CAN && len) > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2278 memset(hw_tx_obj->data + offset, 0x0, len); > 55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine= -Budde 2020-09-18 2279 memcpy(hw_tx_obj->data, cfd->data, cfd->len); =2E..it's only accessed via put_unaligned_* and memset()/memcpy(). Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | --llupkarg5grkzwxh Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEK3kIWJt9yTYMP3ehqclaivrt76kFAmBheE8ACgkQqclaivrt 76mb/ggAialDT5Q0UmXvRXviok/u+ts9aKl88dZGDQGiTbj0pgWdC1XGgfaJfF7g sQEYSG7g9ogJP3hgFMx4NrtWEG24GPDFK7UzHp6adWsyKnAs6vopnO/Q0GZ4fNti ZpUL1sPkOgsoblQPQCcj6OQX43wTW+n+QM14/6lZovYO5WrClaXwRROH+zeWvsCH ENfZ4GhnGPkRHOqRh5hPBUIEhwrhfCAuyqn9OtshBfGw9hVkp5WliVkztej8e0OU O7TbswKA9vbEq7ftxKxiZNFXEPaNUiwxy+yB6Gz2TffkDRfW3sSqDjS51+OYPkha HEarrb0BuRtbHxDnLb5lnENlyLssLA== =k7CE -----END PGP SIGNATURE----- --llupkarg5grkzwxh--