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 ED654C433E6 for ; Mon, 28 Dec 2020 10:47:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C5C2222573 for ; Mon, 28 Dec 2020 10:47:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727181AbgL1Kro (ORCPT ); Mon, 28 Dec 2020 05:47:44 -0500 Received: from wforward3-smtp.messagingengine.com ([64.147.123.22]:40989 "EHLO wforward3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727163AbgL1Kro (ORCPT ); Mon, 28 Dec 2020 05:47:44 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailforward.west.internal (Postfix) with ESMTP id 81A67666; Mon, 28 Dec 2020 05:46:58 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute4.internal (MEProxy); Mon, 28 Dec 2020 05:46:58 -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=WxSVLB E6GBwjH466CfKHt33I+BivRvbqFVzevJQP2GI=; b=K97S/oNrc8lDTMn3O4sMtQ +7YhAjSnhTUjPvtwC9teAfq5Ih//au78J5dH0lKAiBTLQMhQsyOu1TBK4Vua4BRv sqcpzOUVOvcF2J1e7eTpiFKXXCZLkl5TWdRW/TJ41zyqa/3r5ZibA6dOmw8rsiHh 49nJzjrQG2364CnzWYdvdQMja65K/BEavbYQTE+3Gh5Q9CTE1eIo3w/TnRuF2Jsi 4PUt8c1m/grqg2Kteh/r4cYQe8FOCF1ShTdi2cgRBndxAAZWU5tRsrKM8WN7Roe8 SJyceWUyCShhLmRUmBp/C8vHOJxwZZrmL2pnGfNDyqcsRBJEvULFDDR32jsSbUJg == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedujedrvdduledgvdduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucenucfjughrpefuvffhfffkgggtgfesthekredttd dtlfenucfhrhhomhepoehgrhgvghhkhheslhhinhhugihfohhunhgurghtihhonhdrohhr gheqnecuggftrfgrthhtvghrnhepleelledvgeefleeltdetgedugeffgffhudffudduke egfeelgeeigeekjefhleevnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucfkphep keefrdekiedrjeegrdeigeenucevlhhushhtvghrufhiiigvpedunecurfgrrhgrmhepmh 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 C01431080057; Mon, 28 Dec 2020 05:46:57 -0500 (EST) Subject: FAILED: patch "[PATCH] iio: ad_sigma_delta: Don't put SPI transfer buffer on the" failed to apply to 4.9-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: <1609152499176222@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 4.9-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,