dmaengine: apple-admac: Fix 'current_tx' not getting freed

In terminate_all we should queue up all submitted descriptors to be
freed. We do that for the content of the 'issued' and 'submitted' lists,
but the 'current_tx' descriptor falls through the cracks as it's
removed from the 'issued' list once it gets assigned to be the current
descriptor. Explicitly queue up freeing of the 'current_tx' descriptor
to address a memory leak that is otherwise present.

Fixes: b127315d9a78 ("dmaengine: apple-admac: Add Apple ADMAC driver")
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20230224152222.26732-2-povik+lin@cutebit.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/apple-admac.c b/drivers/dma/apple-admac.c
index b9132b4..4cf8da7 100644 (file)
--- a/drivers/dma/apple-admac.c
+++ b/drivers/dma/apple-admac.c
@@ -512,7 +512,10 @@ static int admac_terminate_all(struct dma_chan *chan)
        admac_stop_chan(adchan);
        admac_reset_rings(adchan);
 
-       adchan->current_tx = NULL;
+       if (adchan->current_tx) {
+               list_add_tail(&adchan->current_tx->node, &adchan->to_free);
+               adchan->current_tx = NULL;
+       }
        /*
         * Descriptors can only be freed after the tasklet
         * has been killed (in admac_synchronize).