Re: [PATCH] dmaengine: at_hdmac: fix module unloading

[Ludovic Desroches]

On Tue, Nov 27, 2018 at 05:06:35PM +0100, Richard Genoud wrote:
> of_dma_controller_free() was not called on module onloading.

s/onloading/unloading

> This lead to a soft lockup:
> watchdog: BUG: soft lockup - CPU#0 stuck for 23s!
> Modules linked in: at_hdmac [last unloaded: at_hdmac]
> when of_dma_request_slave_channel() tried to call ofdma->of_dma_xlate().
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding")
> Signed-off-by: Richard Genoud <richard.genoud@xxxxxxxxx>

Acked-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>

Thanks

Ludovic

> ---
>  drivers/dma/at_hdmac.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
> index 1b7f0ca0d5cd..01d936c9fe89 100644
> --- a/drivers/dma/at_hdmac.c
> +++ b/drivers/dma/at_hdmac.c
> @@ -2006,6 +2006,8 @@ static int at_dma_remove(struct platform_device *pdev)
>  	struct resource		*io;
>  
>  	at_dma_off(atdma);
> +	if (pdev->dev.of_node)
> +		of_dma_controller_free(pdev->dev.of_node);
>  	dma_async_device_unregister(&atdma->dma_common);
>  
>  	dma_pool_destroy(atdma->memset_pool);