[PATCH 4/4] crypto: talitos - fix invalid submit_count initial value

[Paul Louvel]

The submit_count atomic counter is initialized to -(chfifo_len - 1), but
since atomic_inc_not_zero() rejects increments when the value is zero,
one FIFO slot is always wasted. With chfifo_len = 24, only 23
descriptors can be submitted before getting -EAGAIN in talitos_submit().

Fix by initializing submit_count to -chfifo_len so that the counter
reaches zero only after all chfifo_len slots are occupied.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 4b99262881213 ("crypto: talitos - align locks on cache lines")
Signed-off-by: Paul Louvel <paul.louvel@xxxxxxxxxxx>
---
 drivers/crypto/talitos.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index 8d063ad5639c..429db3ee9123 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -3575,7 +3575,7 @@ static int talitos_probe(struct platform_device *ofdev)
 		}
 
 		atomic_set(&priv->chan[i].submit_count,
-			   -(priv->chfifo_len - 1));
+			   -priv->chfifo_len);
 	}
 
 	dma_set_mask(dev, DMA_BIT_MASK(36));

-- 
2.53.0