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=-10.5 required=3.0 tests=BAYES_00,INCLUDES_PATCH, MAILING_LIST_MULTI,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 8E0C9C47088 for ; Wed, 26 May 2021 17:07:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 656E1613E1 for ; Wed, 26 May 2021 17:07:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234070AbhEZRJY (ORCPT ); Wed, 26 May 2021 13:09:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:47212 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233955AbhEZRJY (ORCPT ); Wed, 26 May 2021 13:09:24 -0400 Received: from jic23-huawei (cpc108967-cmbg20-2-0-cust86.5-4.cable.virginm.net [81.101.6.87]) (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 C49FE61184; Wed, 26 May 2021 17:07:48 +0000 (UTC) Date: Wed, 26 May 2021 18:09:16 +0100 From: Jonathan Cameron To: linux-iio@vger.kernel.org Cc: Jonathan Cameron , Eugen Hristev , Andreas Klinger , Matt Ranostay , Gwendal Grignou , Song Qiang , Mathieu Othacehe , Parthiban Nallathambi , Andy Shevchenko Subject: Re: [PATCH 00/11] IIO: Alignment fixes part 3 - __aligned(8) used to ensure alignment Message-ID: <20210526180916.5e253ef3@jic23-huawei> In-Reply-To: <20210513185832.515046f9@jic23-huawei> References: <20210501171352.512953-1-jic23@kernel.org> <20210513185832.515046f9@jic23-huawei> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Thu, 13 May 2021 18:58:32 +0100 Jonathan Cameron wrote: > On Sat, 1 May 2021 18:13:41 +0100 > Jonathan Cameron wrote: > > > From: Jonathan Cameron > > Thanks to those who have already provided reviews on this set. > If anyone has time to do a quick sanity check of the remaining patches > it would be much appreciated. I'll pick up the ones which have been reviewed > in a few mins. > > +Cc Andy who was kind enough to look at the other 'parts' of this mega series. Anyone bored? Still looking for a sanity check of the rest of this series before I apply it. I aim to revisit part 4 in the next few days. Jonathan > > Thanks > > Jonathan > > > > > I finally got around to do a manual audit of all the calls to > > iio_push_to_buffers_with_timestamp() which has the somewhat odd requirements > > of: > > 1. 8 byte alignment of the provided buffer. > > 2. space for an 8 byte naturally aligned timestamp to be inserted at the > > end. > > > > Unfortunately there were rather a lot of these left, but time to bite the bullet > > and clean them up. > > > > As discussed previous in > > https://lore.kernel.org/linux-iio/20200920112742.170751-1-jic23@kernel.org/ > > it is not easy to fix the alignment issue without requiring a bounce buffer > > (see part 4 of the alignment fixes for a proposal for that where it is > > absolutely necessary). > > > > Part 3 contains the cases where the struct approach in part 2 did not seem > > appropriate. Normally there are two possible reasons for this. > > 1. Would have required an additional memset operation to avoid any > > possibility of leaking kernel data. > > 2. The location of the timestamp may depend on the channels enabled. > > This normally happens when the max sizeof channels is greater than > > 8 bytes. > > > > Once all cases are fixes, I'll take a look at hardening against any > > accidental reintroductions. Note that on many platforms and usecases the > > bug in question will never occur. > > > > Cc: Eugen Hristev > > Cc: Andreas Klinger > > Cc: Matt Ranostay > > Cc: Gwendal Grignou > > Cc: Song Qiang > > Cc: Mathieu Othacehe > > Cc: Parthiban Nallathambi > > > > Jonathan Cameron (11): > > iio: adc: at91-sama5d2: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > iio: adc: hx711: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > iio: adc: mxs-lradc: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > iio: adc: ti-ads8688: Fix alignment of buffer in > > iio_push_to_buffers_with_timestamp() > > iio: chemical: atlas: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > iio: cros_ec_sensors: Fix alignment of buffer in > > iio_push_to_buffers_with_timestamp() > > iio: potentiostat: lmp91000: Fix alignment of buffer in > > iio_push_to_buffers_with_timestamp() > > iio: magn: rm3100: Fix alignment of buffer in > > iio_push_to_buffers_with_timestamp() > > iio: light: vcnl4000: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > iio: light: vcnl4035: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > iio: prox: isl29501: Fix buffer alignment in > > iio_push_to_buffers_with_timestamp() > > > > drivers/iio/adc/at91-sama5d2_adc.c | 3 ++- > > drivers/iio/adc/hx711.c | 4 ++-- > > drivers/iio/adc/mxs-lradc-adc.c | 3 ++- > > drivers/iio/adc/ti-ads8688.c | 3 ++- > > drivers/iio/chemical/atlas-sensor.c | 4 ++-- > > drivers/iio/light/vcnl4000.c | 2 +- > > drivers/iio/light/vcnl4035.c | 3 ++- > > drivers/iio/magnetometer/rm3100-core.c | 3 ++- > > drivers/iio/potentiostat/lmp91000.c | 4 ++-- > > drivers/iio/proximity/isl29501.c | 2 +- > > include/linux/iio/common/cros_ec_sensors_core.h | 2 +- > > 11 files changed, 19 insertions(+), 14 deletions(-) > > >