[PATCH 4.4 049/114] uio: uio_dmem_genirq: Catch the Exception

[Greg Kroah-Hartman]

From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

[ Upstream commit eec91694f927d1026974444eb6a3adccd4f1cbc2 ]

The return value of dma_set_coherent_mask() is not always 0.
To catch the exception in case that dma is not support the mask.

Fixes: 0a0c3b5a24bd ("Add new uio device for dynamic memory allocation")
Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20211204000326.1592687-1-jiasheng@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/uio/uio_dmem_genirq.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/uio/uio_dmem_genirq.c b/drivers/uio/uio_dmem_genirq.c
index a00b4aee6c799..a31b9d5260ca0 100644
--- a/drivers/uio/uio_dmem_genirq.c
+++ b/drivers/uio/uio_dmem_genirq.c
@@ -194,7 +194,11 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
 		goto bad0;
 	}
 
-	dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+	if (ret) {
+		dev_err(&pdev->dev, "DMA enable failed\n");
+		return ret;
+	}
 
 	priv->uioinfo = uioinfo;
 	spin_lock_init(&priv->lock);
-- 
2.34.1