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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED, USER_AGENT_GIT 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 A80BEC433DB for ; Mon, 28 Dec 2020 14:36:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5D12A2063A for ; Mon, 28 Dec 2020 14:36:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392229AbgL1Ogd (ORCPT ); Mon, 28 Dec 2020 09:36:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:41024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2504886AbgL1OdF (ORCPT ); Mon, 28 Dec 2020 09:33:05 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 00155224D2; Mon, 28 Dec 2020 14:32:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609165944; bh=M+utYt6pr6YBpAd8O1kfh4QtaFja7vdkmDgoY6zssAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RDxer4/rkV6Q3pNQ4OxDxQS3z5plGMjOFu5Ekk/oQ0jloSwlY8xAK0XjpLIMa84lS bymtAe+ReyknmErc4wwMzhJvOYctDydam4O4O0p05XEyKHkwngclzVS03b6DlvS2zT Ef3YHMGR0zdmMsRdDHsKdqrjspZ3/BKZlIWBEJ+c= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Jonathan Cameron , Andy Shevchenko , Alexandru Ardelean , Peter Meerwald , Stable@vger.kernel.org Subject: [PATCH 5.10 680/717] iio:pressure:mpl3115: Force alignment of buffer Date: Mon, 28 Dec 2020 13:51:18 +0100 Message-Id: <20201228125053.558187217@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228125020.963311703@linuxfoundation.org> References: <20201228125020.963311703@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jonathan Cameron commit 198cf32f0503d2ad60d320b95ef6fb8243db857f upstream. Whilst this is another case of the issue Lars reported with an array of elements of smaller than 8 bytes being passed to iio_push_to_buffers_with_timestamp(), the solution here is a bit different from the other cases and relies on __aligned working on the stack (true since 4.6?) This one is unusual. We have to do an explicit memset() each time as we are reading 3 bytes into a potential 4 byte channel which may sometimes be a 2 byte channel depending on what is enabled. As such, moving the buffer to the heap in the iio_priv structure doesn't save us much. We can't use a nice explicit structure on the stack either as the data channels have different storage sizes and are all separately controlled. Fixes: cc26ad455f57 ("iio: Add Freescale MPL3115A2 pressure / temperature sensor driver") Reported-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Reviewed-by: Alexandru Ardelean Cc: Peter Meerwald Cc: Link: https://lore.kernel.org/r/20200920112742.170751-7-jic23@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/iio/pressure/mpl3115.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/drivers/iio/pressure/mpl3115.c +++ b/drivers/iio/pressure/mpl3115.c @@ -144,7 +144,14 @@ static irqreturn_t mpl3115_trigger_handl struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct mpl3115_data *data = iio_priv(indio_dev); - u8 buffer[16]; /* 32-bit channel + 16-bit channel + padding + ts */ + /* + * 32-bit channel + 16-bit channel + padding + ts + * Note that it is possible for only one of the first 2 + * channels to be enabled. If that happens, the first element + * of the buffer may be either 16 or 32-bits. As such we cannot + * use a simple structure definition to express this data layout. + */ + u8 buffer[16] __aligned(8); int ret, pos = 0; mutex_lock(&data->lock);