[PATCH v6 04/16] dmaengine: tegra-apb: Prevent race conditions on channel's freeing

Dmitry Osipenko
2020-01-30T04:42:12Z

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.

Acked-by: Jon Hunter <jonathanh@nvidia.com>
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 f56881500a23..766c2c9eac8e 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