ioat: fix 'ack' handling, driver must ensure that 'ack' is zero

Initialize 'ack' to zero in case the descriptor has been recycled.

Prevents "kernel BUG at crypto/async_tx/async_xor.c:185!"

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Cc: stable@kernel.org

diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c
index dff38accc5c1df47193a73b4fb81e467012d80b6..4017d9e7acd2a2b68020e2584c71dc654dd20cae 100644 (file)
--- a/drivers/dma/ioat_dma.c
+++ b/drivers/dma/ioat_dma.c
@@ -714,6 +714,7 @@ static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
                new->len = len;
                new->dst = dma_dest;
                new->src = dma_src;
+               new->async_tx.ack = 0;
                return &new->async_tx;
        } else
                return NULL;
@@ -741,6 +742,7 @@ static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
                new->len = len;
                new->dst = dma_dest;
                new->src = dma_src;
+               new->async_tx.ack = 0;
                return &new->async_tx;
        } else
                return NULL;