[PATCH] can : TI_HECC : Unintialized variables

[PATCH] can : TI_HECC : Unintialized variables

[Abhilash K V]

1. In ti_hecc_xmit(), "data" is not initialized, causing
   undesirable effects like setting the RTR field for every
   transmit.
2. In ti_hecc_probe(), the spinlock  priv->mbx_lock is not
   inited, causing a spinlock lockup BUG.

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Acked-by: Anant Gole <anantgole@ti.com>
Signed-off-by: Abhilash K V <abhilash.kv@ti.com>
---
 drivers/net/can/ti_hecc.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
index 4d07f1e..73c6025 100644
--- a/drivers/net/can/ti_hecc.c
+++ b/drivers/net/can/ti_hecc.c
@@ -503,6 +503,7 @@ static netdev_tx_t ti_hecc_xmit(struct sk_buff *skb, struct net_device *ndev)
 	spin_unlock_irqrestore(&priv->mbx_lock, flags);
 
 	/* Prepare mailbox for transmission */
+	data = cf->can_dlc;
 	if (cf->can_id & CAN_RTR_FLAG) /* Remote transmission request */
 		data |= HECC_CANMCF_RTR;
 	data |= get_tx_head_prio(priv) << 8;
@@ -923,6 +924,7 @@ static int ti_hecc_probe(struct platform_device *pdev)
 	priv->can.do_get_state = ti_hecc_get_state;
 	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
 
+	spin_lock_init(&priv->mbx_lock);
 	ndev->irq = irq->start;
 	ndev->flags |= IFF_ECHO;
 	platform_set_drvdata(pdev, ndev);
-- 
1.6.2.4

Re: [PATCH] can : TI_HECC : Unintialized variables

[Wolfgang Grandegger]

On 03/10/2011 05:21 PM, Abhilash K V wrote:
> 1. In ti_hecc_xmit(), "data" is not initialized, causing
>    undesirable effects like setting the RTR field for every
>    transmit.

Does it need to be initialized to "data = cf->can_dlc"? If yes, please
correct the message, if not ...

> 2. In ti_hecc_probe(), the spinlock  priv->mbx_lock is not
>    inited, causing a spinlock lockup BUG.
> 
> Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
> Acked-by: Anant Gole <anantgole@ti.com>
> Signed-off-by: Abhilash K V <abhilash.kv@ti.com>
> ---
>  drivers/net/can/ti_hecc.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
> index 4d07f1e..73c6025 100644
> --- a/drivers/net/can/ti_hecc.c
> +++ b/drivers/net/can/ti_hecc.c
> @@ -503,6 +503,7 @@ static netdev_tx_t ti_hecc_xmit(struct sk_buff *skb, struct net_device *ndev)
>  	spin_unlock_irqrestore(&priv->mbx_lock, flags);
>  
>  	/* Prepare mailbox for transmission */
> +	data = cf->can_dlc;
>  	if (cf->can_id & CAN_RTR_FLAG) /* Remote transmission request */
>  		data |= HECC_CANMCF_RTR;
>  	data |= get_tx_head_prio(priv) << 8;

... using the following expressions looks more reasonable:

  	data = get_tx_head_prio(priv) << 8;
 	if (cf->can_id & CAN_RTR_FLAG) /* Remote transmission request */
 		data |= HECC_CANMCF_RTR;
	
Wolfgang.