[PATCH 3.10 117/139] net/mlx4: Remove BUG_ON from ICM allocation routine

[Willy Tarreau]

From: Leon Romanovsky <leonro@xxxxxxxxxxxx>

commit c1d5f8ff80ea84768f5fae1ca9d1abfbb5e6bbaa upstream.

This patch removes BUG_ON() macro from mlx4_alloc_icm_coherent()
by checking DMA address alignment in advance and performing proper
folding in case of error.

Fixes: 5b0bf5e25efe ("mlx4_core: Support ICM tables in coherent memory")
Reported-by: Ozgur Karatas <okaratas@xxxxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
 drivers/net/ethernet/mellanox/mlx4/icm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/icm.c b/drivers/net/ethernet/mellanox/mlx4/icm.c
index 31d0264..d22482b 100644
--- a/drivers/net/ethernet/mellanox/mlx4/icm.c
+++ b/drivers/net/ethernet/mellanox/mlx4/icm.c
@@ -113,8 +113,13 @@ static int mlx4_alloc_icm_coherent(struct device *dev, struct scatterlist *mem,
 	if (!buf)
 		return -ENOMEM;
 
+	if (offset_in_page(buf)) {
+		dma_free_coherent(dev, PAGE_SIZE << order,
+				  buf, sg_dma_address(mem));
+		return -ENOMEM;
+	}
+
 	sg_set_buf(mem, buf, PAGE_SIZE << order);
-	BUG_ON(mem->offset);
 	sg_dma_len(mem) = PAGE_SIZE << order;
 	return 0;
 }
-- 
2.8.0.rc2.1.gbe9624a