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=unavailable 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 347F2C3A589 for ; Tue, 20 Aug 2019 13:42:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A4FE230F2 for ; Tue, 20 Aug 2019 13:42:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566308568; bh=M/vwVB6QzwvIHH0Vg/5xg7oIMCtftMVor+9Icqm10u8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Jpk3O0VWlxIEFlv32OT6WXXCpDSlq34EXxqt3qt0uwXe8m+1Nu0wF5jWQN8pTEGd5 XH0O0BExtmDN9ciyq2pnT9MNI5j6eir8Boa0xejkEOm50HC8hNqTaPhb1UpzIeG72G S31KR3sGjCblhLYDsEsaDJQO01/CITWpbMohaIcE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730715AbfHTNmn (ORCPT ); Tue, 20 Aug 2019 09:42:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:38142 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730682AbfHTNmm (ORCPT ); Tue, 20 Aug 2019 09:42:42 -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 E3F9622DBF; Tue, 20 Aug 2019 13:42:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566308561; bh=M/vwVB6QzwvIHH0Vg/5xg7oIMCtftMVor+9Icqm10u8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tKQmLuRBxq4z+p9G2FfqYbHchS1b4JACcAnFMSRVcu7b+VFk2GX3CYt7OJk3Dzk1m nmL/VJoXzu+3U6EhjiuE4W4Ds4ItygtK0S+HGBnWMel9ERkVFYXVgDkskWrGt6268i uPeSerHZv1beYCdPDHIIM1MlFVbZ/Nu6Q1o3j+6o= 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 4.19 22/27] i2c: rcar: avoid race when unregistering slave client Date: Tue, 20 Aug 2019 09:42:08 -0400 Message-Id: <20190820134213.11279-22-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190820134213.11279-1-sashal@kernel.org> References: <20190820134213.11279-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 254e6219e5389..2c29f901d3090 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) @@ -859,9 +860,11 @@ 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)); @@ -916,7 +919,7 @@ 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; priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL); if (!priv) @@ -979,10 +982,10 @@ 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