[v2,1/3] dmaengine: at_xdmac: remove BUG_ON macro in tasklet

[v2,1/3] dmaengine: at_xdmac: remove BUG_ON macro in tasklet

[Nicolas Ferre]

Even if this case shouldn't happen when controller is properly programmed,
it's still better to avoid dumping a kernel Oops for this.
As the sequence may happen only for debugging purposes, log the error and
just finish the tasklet call.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
---
v2: added Ludovic's tag

 drivers/dma/at_xdmac.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index fe69dccfa0c0..37a269420435 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -1606,7 +1606,11 @@ static void at_xdmac_tasklet(unsigned long data)
 					struct at_xdmac_desc,
 					xfer_node);
 		dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
-		BUG_ON(!desc->active_xfer);
+		if (!desc->active_xfer) {
+			dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
+			spin_unlock_bh(&atchan->lock);
+			return;
+		}
 
 		txd = &desc->tx_dma_desc;
 

[v2,1/3] dmaengine: at_xdmac: remove BUG_ON macro in tasklet

[Nicolas Ferre]

Vinod,

Please disregard this series: I'm sending a v3 right now. Sorry for the 
noise.

Best regards,
   Nicolas

On 03/04/2019 at 12:09, Nicolas Ferre wrote:
> Even if this case shouldn't happen when controller is properly programmed,
> it's still better to avoid dumping a kernel Oops for this.
> As the sequence may happen only for debugging purposes, log the error and
> just finish the tasklet call.
> 
> Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
> ---
> v2: added Ludovic's tag
> 
>   drivers/dma/at_xdmac.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
> index fe69dccfa0c0..37a269420435 100644
> --- a/drivers/dma/at_xdmac.c
> +++ b/drivers/dma/at_xdmac.c
> @@ -1606,7 +1606,11 @@ static void at_xdmac_tasklet(unsigned long data)
>   					struct at_xdmac_desc,
>   					xfer_node);
>   		dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
> -		BUG_ON(!desc->active_xfer);
> +		if (!desc->active_xfer) {
> +			dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
> +			spin_unlock_bh(&atchan->lock);
> +			return;
> +		}
>   
>   		txd = &desc->tx_dma_desc;
>   
> 


-- 
Nicolas Ferre