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 715F0C43461 for ; Mon, 7 Sep 2020 17:12:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34B422080A for ; Mon, 7 Sep 2020 17:12:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599498723; bh=FHTcrPnwNgdAZABEN21HVNkT3V+T3gP6yMDMA/0pYuA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zHflwgv7OgjITO9V4V1goyODbgrxvCkyig9zCzQr5bjOmd841M0y03cbtd0oRQM/N fnzM4pKlrQgZg9RG763g9YWlJjciZf/DDAJ7uSrPjWxV2K5xKqVZbz8wElxpB5DmLG S+pS9J6HGqnJgCV5K/omkiBP9MrIA3Ca77tVAxaI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730981AbgIGRMA (ORCPT ); Mon, 7 Sep 2020 13:12:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:46526 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729847AbgIGQck (ORCPT ); Mon, 7 Sep 2020 12:32:40 -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 EE56821556; Mon, 7 Sep 2020 16:32:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599496357; bh=FHTcrPnwNgdAZABEN21HVNkT3V+T3gP6yMDMA/0pYuA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HHoci7QySEdpYa8Ne/qnSi9sXQGRcqWhh5Sl40UWOnwW3mafxZFfy9TwzCGk1zha5 /VsrhAnm0exAESggc98MVokTQoWZigsGdbXZ1rs5P530/EaXFwUZUYamw7o2vQfGip /tGRtAX7mDqGU7J2sYxNQ0uWdYaMLaySsDU4zDMw= 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 5.8 13/53] drivers/dma/dma-jz4780: Fix race condition between probe and irq handler Date: Mon, 7 Sep 2020 12:31:39 -0400 Message-Id: <20200907163220.1280412-13-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200907163220.1280412-1-sashal@kernel.org> References: <20200907163220.1280412-1-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 448f663da89c6..8beed91428bd6 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -879,24 +879,11 @@ 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); @@ -949,10 +936,23 @@ 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. */ @@ -960,17 +960,17 @@ 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