From patchwork Tue Sep 15 14:12:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 309743 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=-15.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 C701EC43461 for ; Tue, 15 Sep 2020 14:29:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FD9B23D20 for ; Tue, 15 Sep 2020 14:29:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600180190; bh=b8RGyXcP6g9WqOwCH5gMQQmDdR7oyUfGaniALTLI0+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0phRmpUZdXjjHv3/NknUP9SXoo4UkJINTdEy5ftp5hKtLmuN2UhnbcalGpF085hhe 5R5fW0RTb41Hi5ilXorK4zjQqYrL+0+3/DcHaTmaHQkQWYUp0fT34VOTXL90Nco7/n lO0wIXDIm/lbwvTPeeKDHKepCpcPZydkyz19cAa8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726269AbgIOO3B (ORCPT ); Tue, 15 Sep 2020 10:29:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:41427 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726818AbgIOO2f (ORCPT ); Tue, 15 Sep 2020 10:28:35 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B4ADA224B0; Tue, 15 Sep 2020 14:19:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600179598; bh=b8RGyXcP6g9WqOwCH5gMQQmDdR7oyUfGaniALTLI0+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pk8WSvpYNqNoyAA/VBXYmEoygOuf3Uwl09jvkyCUCDYS7o+JNRlSYgKs4Q1KkUTiV lX5E+UPeE1DTU2UnfubPDR4FOLNxo38ZBULXtXtPjgUcCGPSvbG0ppsHdWs10fCe7X +G7zwIXTStNz9B/4LwLheOQcZJfm+jE0eMwylhyw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Madhuparna Bhowmik , Paul Cercueil , Vinod Koul , Sasha Levin Subject: [PATCH 5.4 044/132] drivers/dma/dma-jz4780: Fix race condition between probe and irq handler Date: Tue, 15 Sep 2020 16:12:26 +0200 Message-Id: <20200915140646.328368688@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200915140644.037604909@linuxfoundation.org> References: <20200915140644.037604909@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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; }