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=-8.6 required=3.0 tests=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 40A45C433E0 for ; Sun, 5 Jul 2020 11:55:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1385B2075D for ; Sun, 5 Jul 2020 11:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593950104; bh=PySaQ9280ijbHQQr9O4QujlwIn0LScfCX/BaELoUy5o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=LBwlnam3GQZvxEkViwneXl+ndmjxnUeGFW3a2GPSf46LSRSipraPqAQ8rCuLcOTnq tIre4aei7bTCRLY/IIYrfQGcQoZJOvxCenJYANp28mIbGLriaQRNwMf8dj9IdXNDCn i/7HpC5hubVeQpD3jK1WXH660z2jzvCtGB6vS9X0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726480AbgGELzD (ORCPT ); Sun, 5 Jul 2020 07:55:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:56784 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726454AbgGELzD (ORCPT ); Sun, 5 Jul 2020 07:55:03 -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 E04582073E; Sun, 5 Jul 2020 11:55:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593950102; bh=PySaQ9280ijbHQQr9O4QujlwIn0LScfCX/BaELoUy5o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=RqanaMKwwfzNgOIWn4Iepy9x2SyFj3yhUFFqac1wnsQwrkSSrs93uM3ro9SvymKVM KOYYo0liVxn8kMBMHRvI5n4R7Hjv2HU5r3INtnx0Q9Dmr43FVVgL9PEQm5xcdbqmP1 D7kFG62KuI5hbDpEKBjkjTbyFco8RlRMnET4hMz4= Date: Sun, 5 Jul 2020 12:54:59 +0100 From: Jonathan Cameron To: Tomasz Duszynski Cc: , Andy Shevchenko , Jonathan Cameron , Lars-Peter Clausen Subject: Re: [PATCH 21/32] iio:pressure:ms5611 Fix buffer element alignment Message-ID: <20200705125459.32fb5457@archlinux> In-Reply-To: <20200607180313.GA95841@arch> References: <20200607155408.958437-1-jic23@kernel.org> <20200607155408.958437-22-jic23@kernel.org> <20200607180313.GA95841@arch> X-Mailer: Claws Mail 3.17.5 (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 Sun, 7 Jun 2020 20:03:13 +0200 Tomasz Duszynski wrote: > On Sun, Jun 07, 2020 at 04:53:57PM +0100, Jonathan Cameron wrote: > > From: Jonathan Cameron > > > > One of a class of bugs pointed out by Lars in a recent review. > > iio_push_to_buffers_with_timestamp assumes the buffer used is aligned > > to the size of the timestamp (8 bytes). This is not guaranteed in > > this driver which uses an array of smaller elements on the stack. > > Here there is no data leak possibility so use an explicit structure > > on the stack to ensure alignment and nice readable fashion. > > > > The forced alignment of ts isn't strictly necessary in this driver > > as the padding will be correct anyway (there isn't any). However > > it is probably less fragile to have it there and it acts as > > documentation of the requirement. > > > > Looks good. > Acked-by: Tomasz Duszynski Applied to the fixes-togreg branch of iio.git and marked for stable. I'm picking up those patch in the series for which I have an ack to cut down on the number we need to consider in the next version. Thanks, Jonathan > > > Fixes: 713bbb4efb9dc ("iio: pressure: ms5611: Add triggered buffer support") > > Reported-by: Lars-Peter Clausen > > Signed-off-by: Jonathan Cameron > > --- > > drivers/iio/pressure/ms5611_core.c | 11 ++++++++--- > > 1 file changed, 8 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/iio/pressure/ms5611_core.c b/drivers/iio/pressure/ms5611_core.c > > index d451bb9dffc8..214b0d25f598 100644 > > --- a/drivers/iio/pressure/ms5611_core.c > > +++ b/drivers/iio/pressure/ms5611_core.c > > @@ -212,16 +212,21 @@ static irqreturn_t ms5611_trigger_handler(int irq, void *p) > > struct iio_poll_func *pf = p; > > struct iio_dev *indio_dev = pf->indio_dev; > > struct ms5611_state *st = iio_priv(indio_dev); > > - s32 buf[4]; /* s32 (pressure) + s32 (temp) + 2 * s32 (timestamp) */ > > + /* Ensure buffer elements are naturally aligned */ > > + struct { > > + s32 channels[2]; > > + s64 ts __aligned(8); > > + } scan; > > int ret; > > > > mutex_lock(&st->lock); > > - ret = ms5611_read_temp_and_pressure(indio_dev, &buf[1], &buf[0]); > > + ret = ms5611_read_temp_and_pressure(indio_dev, &scan.channels[1], > > + &scan.channels[0]); > > mutex_unlock(&st->lock); > > if (ret < 0) > > goto err; > > > > - iio_push_to_buffers_with_timestamp(indio_dev, buf, > > + iio_push_to_buffers_with_timestamp(indio_dev, &scan, > > iio_get_time_ns(indio_dev)); > > > > err: > > -- > > 2.26.2 > >