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=-16.1 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 2E45DC43463 for ; Fri, 18 Sep 2020 02:22:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E011323730 for ; Fri, 18 Sep 2020 02:22:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395736; bh=YdD/Nvo27G+e8nrcZ5gaxYJze7xGEk/EPg48EyObEbQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FOC1rxyWZAeaM64ruO7V8doUT8mkpylpda3WJCtKsouACstPO2kjt0BHF4YkClSPx 33wiiqyUUqGIHKfQxkB9/pUR6TAvYpW8atrtkQTr5QyU+bbbVsovzsw7fFGyoutlYJ YUOYaHvnL7txMoh+2m33hXe3aqjWvYsuTa3S/NEA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729761AbgIRCWO (ORCPT ); Thu, 17 Sep 2020 22:22:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:48014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728051AbgIRCRY (ORCPT ); Thu, 17 Sep 2020 22:17:24 -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 4D59423A02; Fri, 18 Sep 2020 02:17:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395439; bh=YdD/Nvo27G+e8nrcZ5gaxYJze7xGEk/EPg48EyObEbQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=boYhox2MjhW2L4KYPNyqw96EC858rsb5ekoc2XWgoRhNGzTqiUdJ6fEjAG8UeAeky +cjBaJjY6oXYga4/LLYm86YFcl9sHgzuERKKpKe61oo9unJmAg76+hN+/rIbEemNg1 Y/xgWrtvVBRlcd0rn8PmBu9kp96FXBXVtG1YQQKU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dmitry Osipenko , Jon Hunter , Vinod Koul , Sasha Levin , dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 28/64] dmaengine: tegra-apb: Prevent race conditions on channel's freeing Date: Thu, 17 Sep 2020 22:16:07 -0400 Message-Id: <20200918021643.2067895-28-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918021643.2067895-1-sashal@kernel.org> References: <20200918021643.2067895-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dmitry Osipenko [ Upstream commit 8e84172e372bdca20c305d92d51d33640d2da431 ] It's incorrect to check the channel's "busy" state without taking a lock. That shouldn't cause any real troubles, nevertheless it's always better not to have any race conditions in the code. Signed-off-by: Dmitry Osipenko Acked-by: Jon Hunter Link: https://lore.kernel.org/r/20200209163356.6439-5-digetx@gmail.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/tegra20-apb-dma.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index b5cf5d36de2b4..68c460a2b16ea 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1207,8 +1207,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); - if (tdc->busy) - tegra_dma_terminate_all(dc); + tegra_dma_terminate_all(dc); spin_lock_irqsave(&tdc->lock, flags); list_splice_init(&tdc->pending_sg_req, &sg_req_list); -- 2.25.1