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=-10.1 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,URIBL_BLOCKED,USER_AGENT_GIT 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 75A0EC3A589 for ; Tue, 20 Aug 2019 13:46:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 415802332B for ; Tue, 20 Aug 2019 13:46:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566308800; bh=FZTiyXTGbrBnO4A4A5C/NOMrct+bw+wFQgXkhRD+Alk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ZsItcu/aArBDQznABVzBrqqVGapM2hg0pC1INKa6ttJPlL6uc/i+jfJE3hY5sAJ/t IU4nN+IcN8RQVhBUcFIxDldGAv+px52iZRHGPF/p/Qc3vKlocxflTn/T7qMe+tOx94 Q7k92Vn2roSMhdIUVF9Ty4tkVa7RRHCcUCcxpPCk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730733AbfHTNqj (ORCPT ); Tue, 20 Aug 2019 09:46:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:37024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730478AbfHTNlv (ORCPT ); Tue, 20 Aug 2019 09:41:51 -0400 Received: from sasha-vm.mshome.net (unknown [12.236.144.82]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C937A22DA7; Tue, 20 Aug 2019 13:41:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566308510; bh=FZTiyXTGbrBnO4A4A5C/NOMrct+bw+wFQgXkhRD+Alk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GWQod67Ki19yN6zLGqHTTL3Gtwu8aIgSwfBkAhV/a4+TIndAONXqII2i62p9fQby2 sETBq5SVxcGQvMzyJadQhSAwf8RdpCfB4EbDh0voiGlFgYjs8iW6VK9pGCltAYixpG pwg2omkarUh+4FLwMTbRIZesFsnX5BAl0GGaNMUw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Wolfram Sang , Krzysztof Adamski , Wolfram Sang , Sasha Levin , linux-i2c@vger.kernel.org Subject: [PATCH AUTOSEL 5.2 38/44] i2c: rcar: avoid race when unregistering slave client Date: Tue, 20 Aug 2019 09:40:22 -0400 Message-Id: <20190820134028.10829-38-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190820134028.10829-1-sashal@kernel.org> References: <20190820134028.10829-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wolfram Sang [ Upstream commit 7b814d852af6944657c2961039f404c4490771c0 ] After we disabled interrupts, there might still be an active one running. Sync before clearing the pointer to the slave device. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Reported-by: Krzysztof Adamski Signed-off-by: Wolfram Sang Reviewed-by: Krzysztof Adamski Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-rcar.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index d39a4606f72d3..531c01100b560 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -139,6 +139,7 @@ struct rcar_i2c_priv { enum dma_data_direction dma_direction; struct reset_control *rstc; + int irq; }; #define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent) @@ -861,9 +862,11 @@ static int rcar_unreg_slave(struct i2c_client *slave) WARN_ON(!priv->slave); + /* disable irqs and ensure none is running before clearing ptr */ rcar_i2c_write(priv, ICSIER, 0); rcar_i2c_write(priv, ICSCR, 0); + synchronize_irq(priv->irq); priv->slave = NULL; pm_runtime_put(rcar_i2c_priv_to_dev(priv)); @@ -918,7 +921,7 @@ static int rcar_i2c_probe(struct platform_device *pdev) struct i2c_adapter *adap; struct device *dev = &pdev->dev; struct i2c_timings i2c_t; - int irq, ret; + int ret; /* Otherwise logic will break because some bytes must always use PIO */ BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length"); @@ -984,10 +987,10 @@ static int rcar_i2c_probe(struct platform_device *pdev) pm_runtime_put(dev); - irq = platform_get_irq(pdev, 0); - ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0, dev_name(dev), priv); + priv->irq = platform_get_irq(pdev, 0); + ret = devm_request_irq(dev, priv->irq, rcar_i2c_irq, 0, dev_name(dev), priv); if (ret < 0) { - dev_err(dev, "cannot get irq %d\n", irq); + dev_err(dev, "cannot get irq %d\n", priv->irq); goto out_pm_disable; } -- 2.20.1