2011-03-10 16:21:39

by Abhilash K V

[permalink] [raw]
Subject: [PATCH] can : TI_HECC : Unintialized variables

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 <[email protected]>
Acked-by: Anant Gole <[email protected]>
Signed-off-by: Abhilash K V <[email protected]>
---
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


2011-03-10 17:05:29

by Wolfgang Grandegger

[permalink] [raw]
Subject: Re: [PATCH] can : TI_HECC : Unintialized variables

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 <[email protected]>
> Acked-by: Anant Gole <[email protected]>
> Signed-off-by: Abhilash K V <[email protected]>
> ---
> 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.