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From:   Dmitry Osipenko <digetx@gmail.com>
To:     Laxman Dewangan <ldewangan@nvidia.com>,
        Vinod Koul <vkoul@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= <mirq-linux@rere.qmqm.pl>
Cc:     dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH v3 03/13] dmaengine: tegra-apb: Prevent race conditions on channel's freeing
Date:   Mon,  6 Jan 2020 04:16:58 +0300
Message-Id: <20200106011708.7463-4-digetx@gmail.com>
In-Reply-To: <20200106011708.7463-1-digetx@gmail.com>
References: <20200106011708.7463-1-digetx@gmail.com>
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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 <digetx@gmail.com>
---
 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 664e9c5df3ba..24ad3a5a04e3 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -1294,8 +1294,7 @@ 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);
-- 
2.24.0