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=-11.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 2B94DC433DF for ; Sun, 9 Aug 2020 17:17:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 04861206C3 for ; Sun, 9 Aug 2020 17:17:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596993467; bh=HqCmB91dp9wJXUfZ4P5DScloKB8YtYKjt9MQu6txdqg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=S5l+rKP875FLSxQR8KWBzQNS5w6NQFoFFkDI/oozaylYzEOm5hJ80/vSPwsH1num9 NQW3RpGh4sVHBQxxDrv39jn5Be8ELBBOb5R+QhiV1dbtna0p2FCcu38RhQQVcyNH2B QZfTBNgROXWweErTZ5pRZd9VE3RHGOIbiDu9/IcQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726323AbgHIRRq (ORCPT ); Sun, 9 Aug 2020 13:17:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:53972 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726175AbgHIRRp (ORCPT ); Sun, 9 Aug 2020 13:17:45 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4437C206CD; Sun, 9 Aug 2020 17:17:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596993465; bh=HqCmB91dp9wJXUfZ4P5DScloKB8YtYKjt9MQu6txdqg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=fLdTc83DSJBXydjL8xsSdkGOFtvcZaODxnZ9PXYicXoeA3It8/S8Y9UbvAgssERZj Jcs3YHDKZ0kXI6450A/y9RKCxcnck58sH4pCP75mRxaLA1COIqfKurqZl45PFLhNDU nlXjDhcXzufco+Y7OwSZKha+V66BMIC8sKnr+YXs= Date: Sun, 9 Aug 2020 18:07:21 +0100 From: Jonathan Cameron To: linux-iio@vger.kernel.org Cc: Andy Shevchenko , Lars-Peter Clausen , Peter Meerwald , Jonathan Cameron Subject: Re: [PATCH v3 01/27] iio: accel: kxsd9: Fix alignment of local buffer. Message-ID: <20200809180721.643946ab@archlinux> In-Reply-To: <20200722155103.979802-2-jic23@kernel.org> References: <20200722155103.979802-1-jic23@kernel.org> <20200722155103.979802-2-jic23@kernel.org> X-Mailer: Claws Mail 3.17.6 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Wed, 22 Jul 2020 16:50:37 +0100 Jonathan Cameron wrote: > From: Jonathan Cameron > > iio_push_to_buffers_with_timestamp assumes 8 byte alignment which > is not guaranteed by an array of smaller elements. > > Note that whilst in this particular case the alignment forcing > of the ts element is not strictly necessary it acts as good > documentation. Doing this where not necessary should cut > down on the number of cut and paste introduced errors elsewhere. > > Reported-by: Lars-Peter Clausen > Signed-off-by: Jonathan Cameron Applied to the fixes-togreg branch of iio.git and marked for stable. Thanks, Jonathan > --- > drivers/iio/accel/kxsd9.c | 16 +++++++++++----- > 1 file changed, 11 insertions(+), 5 deletions(-) > > diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c > index 66b2e4cf24cf..0e18b92e2099 100644 > --- a/drivers/iio/accel/kxsd9.c > +++ b/drivers/iio/accel/kxsd9.c > @@ -209,14 +209,20 @@ static irqreturn_t kxsd9_trigger_handler(int irq, void *p) > const struct iio_poll_func *pf = p; > struct iio_dev *indio_dev = pf->indio_dev; > struct kxsd9_state *st = iio_priv(indio_dev); > + /* > + * Ensure correct positioning and alignment of timestamp. > + * No need to zero initialize as all elements written. > + */ > + struct { > + __be16 chan[4]; > + s64 ts __aligned(8); > + } hw_values; > int ret; > - /* 4 * 16bit values AND timestamp */ > - __be16 hw_values[8]; > > ret = regmap_bulk_read(st->map, > KXSD9_REG_X, > - &hw_values, > - 8); > + hw_values.chan, > + sizeof(hw_values.chan)); > if (ret) { > dev_err(st->dev, > "error reading data\n"); > @@ -224,7 +230,7 @@ static irqreturn_t kxsd9_trigger_handler(int irq, void *p) > } > > iio_push_to_buffers_with_timestamp(indio_dev, > - hw_values, > + &hw_values, > iio_get_time_ns(indio_dev)); > iio_trigger_notify_done(indio_dev->trig); >