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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 AAE9DC433DB for ; Mon, 28 Dec 2020 10:47:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7BD732242A for ; Mon, 28 Dec 2020 10:47:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727171AbgL1Krn (ORCPT ); Mon, 28 Dec 2020 05:47:43 -0500 Received: from wforward3-smtp.messagingengine.com ([64.147.123.22]:36217 "EHLO wforward3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727163AbgL1Krm (ORCPT ); Mon, 28 Dec 2020 05:47:42 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailforward.west.internal (Postfix) with ESMTP id 18239405; Mon, 28 Dec 2020 05:46:56 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute4.internal (MEProxy); Mon, 28 Dec 2020 05:46:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; bh=cc1cJr mX+6JPcQpOzZhJE2z/IptlnLPvA/0Jy/VrAnY=; b=WcYu6lwQ3kWGxJOotihvfg Qd+5IJ+K/WSzSZtrjVBHLvkgAghKTDuBLsGAbaCuKR6xSZW4K+ifwhN7aNa/q4EW 1pt+JGk+RpXBubFnUid4XdpYRD9xTIqACjf7CMYEvQ2d+DmEmnN3A6fnNbKodfly KOF1Se+gDYjVvXl0xekPGk6RfRudJDyfxjU6VW65Onjwd8YOabmIqaR27cXPERqf KLevBioEou/J5wZipW/rmyvXmrnSC8DJoMLRajn7F11Yej//ceEF3Vq0t0endski NGHRH6TAgStZd7Y3LmJyLRZ4cR8U6zHGslsMOEyMo2nte/djxVhSdEy0+zWxV/Mw == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedujedrvdduledgvdduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucenucfjughrpefuvffhfffkgggtgfesthekredttd dtlfenucfhrhhomhepoehgrhgvghhkhheslhhinhhugihfohhunhgurghtihhonhdrohhr gheqnecuggftrfgrthhtvghrnhepleelledvgeefleeltdetgedugeffgffhudffudduke egfeelgeeigeekjefhleevnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucfkphep keefrdekiedrjeegrdeigeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmh grihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) by mail.messagingengine.com (Postfix) with ESMTPA id BCB4424005B; Mon, 28 Dec 2020 05:46:55 -0500 (EST) Subject: FAILED: patch "[PATCH] iio: ad_sigma_delta: Don't put SPI transfer buffer on the" failed to apply to 4.4-stable tree To: lars@metafoo.de, Jonathan.Cameron@huawei.com, Stable@vger.kernel.org, alexandru.ardelean@analog.com Cc: From: Date: Mon, 28 Dec 2020 11:48:19 +0100 Message-ID: <16091524997238@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 0fb6ee8d0b5e90b72f870f76debc8bd31a742014 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Tue, 24 Nov 2020 14:38:07 +0200 Subject: [PATCH] iio: ad_sigma_delta: Don't put SPI transfer buffer on the stack Use a heap allocated memory for the SPI transfer buffer. Using stack memory can corrupt stack memory when using DMA on some systems. This change moves the buffer from the stack of the trigger handler call to the heap of the buffer of the state struct. The size increases takes into account the alignment for the timestamp, which is 8 bytes. The 'data' buffer is split into 'tx_buf' and 'rx_buf', to make a clearer separation of which part of the buffer should be used for TX & RX. Fixes: af3008485ea03 ("iio:adc: Add common code for ADI Sigma Delta devices") Signed-off-by: Lars-Peter Clausen Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20201124123807.19717-1-alexandru.ardelean@analog.com Cc: Signed-off-by: Jonathan Cameron diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c index 86039e9ecaca..3a6f239d4acc 100644 --- a/drivers/iio/adc/ad_sigma_delta.c +++ b/drivers/iio/adc/ad_sigma_delta.c @@ -57,7 +57,7 @@ EXPORT_SYMBOL_GPL(ad_sd_set_comm); int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg, unsigned int size, unsigned int val) { - uint8_t *data = sigma_delta->data; + uint8_t *data = sigma_delta->tx_buf; struct spi_transfer t = { .tx_buf = data, .len = size + 1, @@ -99,7 +99,7 @@ EXPORT_SYMBOL_GPL(ad_sd_write_reg); static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta, unsigned int reg, unsigned int size, uint8_t *val) { - uint8_t *data = sigma_delta->data; + uint8_t *data = sigma_delta->tx_buf; int ret; struct spi_transfer t[] = { { @@ -146,22 +146,22 @@ int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta, { int ret; - ret = ad_sd_read_reg_raw(sigma_delta, reg, size, sigma_delta->data); + ret = ad_sd_read_reg_raw(sigma_delta, reg, size, sigma_delta->rx_buf); if (ret < 0) goto out; switch (size) { case 4: - *val = get_unaligned_be32(sigma_delta->data); + *val = get_unaligned_be32(sigma_delta->rx_buf); break; case 3: - *val = get_unaligned_be24(&sigma_delta->data[0]); + *val = get_unaligned_be24(sigma_delta->rx_buf); break; case 2: - *val = get_unaligned_be16(sigma_delta->data); + *val = get_unaligned_be16(sigma_delta->rx_buf); break; case 1: - *val = sigma_delta->data[0]; + *val = sigma_delta->rx_buf[0]; break; default: ret = -EINVAL; @@ -395,11 +395,9 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p) struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); + uint8_t *data = sigma_delta->rx_buf; unsigned int reg_size; unsigned int data_reg; - uint8_t data[16]; - - memset(data, 0x00, 16); reg_size = indio_dev->channels[0].scan_type.realbits + indio_dev->channels[0].scan_type.shift; diff --git a/include/linux/iio/adc/ad_sigma_delta.h b/include/linux/iio/adc/ad_sigma_delta.h index a3a838dcf8e4..7199280d89ca 100644 --- a/include/linux/iio/adc/ad_sigma_delta.h +++ b/include/linux/iio/adc/ad_sigma_delta.h @@ -79,8 +79,12 @@ struct ad_sigma_delta { /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. + * 'tx_buf' is up to 32 bits. + * 'rx_buf' is up to 32 bits per sample + 64 bit timestamp, + * rounded to 16 bytes to take into account padding. */ - uint8_t data[4] ____cacheline_aligned; + uint8_t tx_buf[4] ____cacheline_aligned; + uint8_t rx_buf[16] __aligned(8); }; static inline int ad_sigma_delta_set_channel(struct ad_sigma_delta *sd,