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

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c
index dff38accc5c1..4017d9e7acd2 100644
--- 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;