On 6/2/25 01:42, Qasim Ijaz wrote:
> hidma_ll_init() allocates a handoff FIFO, but the matching
> hidma_ll_uninit() function (which is invoked in remove())
> never releases it, leaking memory.
>
> To fix this call kfifo_free in hidma_ll_uninit().
>
> Fixes: d1615ca2e085 ("dmaengine: qcom_hidma: implement lower level hardware interface")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Qasim Ijaz <qasdev00@xxxxxxxxx>
>
> ---
> drivers/dma/qcom/hidma_ll.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/dma/qcom/hidma_ll.c b/drivers/dma/qcom/hidma_ll.c
> index fee448499777..0c2bae46746c 100644
> --- a/drivers/dma/qcom/hidma_ll.c
> +++ b/drivers/dma/qcom/hidma_ll.c
> @@ -816,6 +816,7 @@ int hidma_ll_uninit(struct hidma_lldev *lldev)
>
> required_bytes = sizeof(struct hidma_tre) * lldev->nr_tres;
> tasklet_kill(&lldev->task);
> + kfifo_free(&lldev->handoff_fifo);
> memset(lldev->trepool, 0, required_bytes);
> lldev->trepool = NULL;
> atomic_set(&lldev->pending_tre_count, 0);
Is it possible that the handoff_fifo is freed, then we could observe
reset complete interrupts before they are being cleared in
hidma_ll_uninit later on, which would lead to the following call chain
hidma_ll_inthandler - hidma_ll_int_handler_internal -
hidma_handle_tre_completion - hidma_post_completed -
tasklet_schedule(&lldev->task); - hidma_ll_tre_complete - kfifo_out
?
