Re: [PATCH] dmaengine: mv_xor: kill tasklet on channel add error path

From: Frank Li

Date: Wed Sep 09 2026 - 21:36:17 EST


On Wed, Sep 09, 2026 at 04:46:01PM -0700, Rosen Penev wrote:
> If request_irq() succeeds but a later step (self-test or device
> registration) fails, the error path at err_free_irq frees the IRQ
> but does not kill the tasklet. A previously scheduled tasklet can
> still run after the channel is freed, accessing freed memory.
>
> Add tasklet_kill() after free_irq() on the error path.
>
> Fixes: ff7b04796d98 ("dmaengine: DMA engine driver for Marvell XOR engine")
> Assisted-by: opencode:big-pickle
> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
> ---

Reviewed-by: Frank Li <Frank.Li@xxxxxxx>

> drivers/dma/mv_xor.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
> index 25ed61f1b089..24f22db5dfa1 100644
> --- a/drivers/dma/mv_xor.c
> +++ b/drivers/dma/mv_xor.c
> @@ -1162,6 +1162,7 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
>
> err_free_irq:
> free_irq(mv_chan->irq, mv_chan);
> + tasklet_kill(&mv_chan->irq_tasklet);
> err_free_dma:
> dma_free_wc(&pdev->dev, MV_XOR_POOL_SIZE,
> mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool);
> --
> 2.55.0
>