From patchwork Mon Dec 28 12:50:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 352766 Delivered-To: patch@linaro.org Received: by 2002:a17:906:4755:0:0:0:0 with SMTP id j21csp10030037ejs; Mon, 28 Dec 2020 08:30:54 -0800 (PST) X-Google-Smtp-Source: ABdhPJzh2UYuRZEc34G6CqXWGPd/WFOhFxK4Es71lSGzaeBw8WriUNO1FYCG0qbwtpDJi4D65SyD X-Received: by 2002:aa7:cccf:: with SMTP id y15mr43000945edt.112.1609173054513; Mon, 28 Dec 2020 08:30:54 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1609173054; cv=none; d=google.com; s=arc-20160816; b=E3SnXwOUO2a2Gt4oDqzDSUgEJaXXA0f9STcrc7bStZUj3yfmm/hVGfopbabtsdAQJL mzHq0H7dTBOWqx+ge6skusFU6XLXjxRRFx2Ex1Sk21UTYoe1v/4JJIAHuSuUJxJXbsxQ Mz+dZXHfWTyZFFmvXd1bn8iI+QoqKkhLNy1XwpQuSVcYFFU5Wtv0lSTZ4lR5pWu3LYC7 GfI7b0TDkyB2ismQp1j+zugkNV5BYDrZchtO2+r7SiYyAgMmV9YpjpZBKGy6xy0fjuZv 5tcz/wldzwYWRVddr8AAPbouBuRBPT4RLlijWIYCQT4bFCMCOdXDzwTu+3AMw5q0Ejok +QOg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=j6EvLzoFniyoxR670iclUWvaOeC85/ZapuKVa/cXP5w=; b=L+TYE9lgo/+shP8rmjmhM4dxi9uONjzudVLGenVJvcJ1ItdHf4++gB4QaNz1lNX7Ag Ia3gnQUcdW3svZJecufYnXAJGat5GD6p+CGEAjb/fEj1BT2C3Cn6D54WFNr08FccRHQF 92E4KJ9TTt6tSqewPEEh+Cov308PUeMZ5Bzf7pSIMusVlNITR71fCIgQ9/kzu9FzvNnZ Hq0SFc2iA94W9LjEAPWO3yXjWHMbDqH1ujzkcu11BygUQCbXOYS+P6Xu+nNAq/Z7wtud fD+XudgFBqEHNmkd9YDYpRAZhe5vqba8SISqD062V6JZTzgqn8hNS6JW5sKJi2vT4F20 EVEw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=yCi+N6lT; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id s18si16958366eji.157.2020.12.28.08.30.54; Mon, 28 Dec 2020 08:30:54 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=yCi+N6lT; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2633596AbgL1Q30 (ORCPT + 14 others); Mon, 28 Dec 2020 11:29:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:34940 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730697AbgL1NHM (ORCPT ); Mon, 28 Dec 2020 08:07:12 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6601B206ED; Mon, 28 Dec 2020 13:06:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609160792; bh=U/rmShT16J06mM0R42BKT9PDN+UC8RCxGEEbHBvPTYo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yCi+N6lTd85IRVYYfm1VnMS/kiPEH/tB8D+f1RoE5Qw0o2vu2nbk3Gu4Xw+kIx7e4 hDSP5iVQLa4IYeY+AQIBYMB82KFXalUGKbJmCz2iNNGBWGfyTUUm3Is3+5PGQryi5J v8ETHDwdk9Wrn2Kunk+d2iRQfbuOFnQa3kzjZmtM= 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 4.9 172/175] iio:pressure:mpl3115: Force alignment of buffer Date: Mon, 28 Dec 2020 13:50:25 +0100 Message-Id: <20201228124901.562817115@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124853.216621466@linuxfoundation.org> References: <20201228124853.216621466@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -139,7 +139,14 @@ 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);