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=-13.2 required=3.0 tests=BAYES_00,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 EBCECC433E2 for ; Mon, 7 Sep 2020 16:36:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B3D5421927 for ; Mon, 7 Sep 2020 16:36:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599496615; bh=b8RGyXcP6g9WqOwCH5gMQQmDdR7oyUfGaniALTLI0+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=n1dJT+QV4P9tBI9b8CtRxHMNLdY7BoWzx5fsMIXOvnZJkrb0G/7Q8Kep7NJzSkEXp 4boJkZOE+IhjL0QqZMNgv1CUUaCNaVY3OvHh32bUNj/BN43BGcjW1aqgvpJvpSanGm +1fEZUsD1FXRBMoXxhPT+o2Ez2jsT4tDV/43+Z7M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730501AbgIGQgr (ORCPT ); Mon, 7 Sep 2020 12:36:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:47458 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730473AbgIGQdn (ORCPT ); Mon, 7 Sep 2020 12:33:43 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 551BF21974; Mon, 7 Sep 2020 16:33:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599496423; bh=b8RGyXcP6g9WqOwCH5gMQQmDdR7oyUfGaniALTLI0+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MFVHHJRGHPbs94InQYz+yvj16Xih48GqhLRibkDFd4T1O2N/chDEwR426szcpbTZt hXFTtwwNJwW639qW1eC6/C3bfecRojKBHp/1grHbPHbM9TywLuEcPPCgh9pR3mcI7L rGV8TL1z5S/DOQnHuIYhZEtZExkqKdKf/YHMxG7I= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Madhuparna Bhowmik , Paul Cercueil , Vinod Koul , Sasha Levin , dmaengine@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 10/43] drivers/dma/dma-jz4780: Fix race condition between probe and irq handler Date: Mon, 7 Sep 2020 12:32:56 -0400 Message-Id: <20200907163329.1280888-10-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200907163329.1280888-1-sashal@kernel.org> References: <20200907163329.1280888-1-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: Madhuparna Bhowmik [ Upstream commit 6d6018fc30bee67290dbed2fa51123f7c6f3d691 ] In probe, IRQ is requested before zchan->id is initialized which can be read in the irq handler. Hence, shift request irq after other initializations complete. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Madhuparna Bhowmik Reviewed-by: Paul Cercueil Link: https://lore.kernel.org/r/20200821034423.12713-1-madhuparnabhowmik10@gmail.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/dma-jz4780.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c index bf95f1d551c51..0ecb724b394f5 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -885,24 +885,11 @@ static int jz4780_dma_probe(struct platform_device *pdev) return -EINVAL; } - ret = platform_get_irq(pdev, 0); - if (ret < 0) - return ret; - - jzdma->irq = ret; - - ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev), - jzdma); - if (ret) { - dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); - return ret; - } - jzdma->clk = devm_clk_get(dev, NULL); if (IS_ERR(jzdma->clk)) { dev_err(dev, "failed to get clock\n"); ret = PTR_ERR(jzdma->clk); - goto err_free_irq; + return ret; } clk_prepare_enable(jzdma->clk); @@ -955,10 +942,23 @@ static int jz4780_dma_probe(struct platform_device *pdev) jzchan->vchan.desc_free = jz4780_dma_desc_free; } + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto err_disable_clk; + + jzdma->irq = ret; + + ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev), + jzdma); + if (ret) { + dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); + goto err_disable_clk; + } + ret = dmaenginem_async_device_register(dd); if (ret) { dev_err(dev, "failed to register device\n"); - goto err_disable_clk; + goto err_free_irq; } /* Register with OF DMA helpers. */ @@ -966,17 +966,17 @@ static int jz4780_dma_probe(struct platform_device *pdev) jzdma); if (ret) { dev_err(dev, "failed to register OF DMA controller\n"); - goto err_disable_clk; + goto err_free_irq; } dev_info(dev, "JZ4780 DMA controller initialised\n"); return 0; -err_disable_clk: - clk_disable_unprepare(jzdma->clk); - err_free_irq: free_irq(jzdma->irq, jzdma); + +err_disable_clk: + clk_disable_unprepare(jzdma->clk); return ret; } -- 2.25.1