Re: [PATCH net] bcm63xx_enet: fix sporadic kernel panic

[Jakub Kicinski]

On Sun, 21 Feb 2021 21:05:50 -0800 Florian Fainelli wrote:
> On 2/21/2021 17:35, Sieng Piaw Liew wrote:
> > In ndo_stop functions, netdev_completed_queue() is called during forced
> > tx reclaim, after netdev_reset_queue(). This may trigger kernel panic if
> > there is any tx skb left.
> > 
> > This patch moves netdev_reset_queue() to after tx reclaim, so BQL can
> > complete successfully then reset.
> > 
> > Signed-off-by: Sieng Piaw Liew   
> 
> Acked-by: Florian Fainelli 
> Fixes: 4c59b0f5543d ("bcm63xx_enet: add BQL support")

Applied, thanks!

Re: [PATCH net] bcm63xx_enet: fix sporadic kernel panic

[Florian Fainelli]

On 2/21/2021 17:35, Sieng Piaw Liew wrote:

In ndo_stop functions, netdev_completed_queue() is called during forced
tx reclaim, after netdev_reset_queue(). This may trigger kernel panic if
there is any tx skb left.

This patch moves netdev_reset_queue() to after tx reclaim, so BQL can
complete successfully then reset.

Signed-off-by: Sieng Piaw Liew 


Acked-by: Florian Fainelli 
Fixes: 4c59b0f5543d ("bcm63xx_enet: add BQL support")
--
Florian

[PATCH net] bcm63xx_enet: fix sporadic kernel panic

[Sieng Piaw Liew]

In ndo_stop functions, netdev_completed_queue() is called during forced
tx reclaim, after netdev_reset_queue(). This may trigger kernel panic if
there is any tx skb left.

This patch moves netdev_reset_queue() to after tx reclaim, so BQL can
complete successfully then reset.

Signed-off-by: Sieng Piaw Liew 
---
 drivers/net/ethernet/broadcom/bcm63xx_enet.c | 8 ++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bcm63xx_enet.c 
b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
index fd8767213165..977f097fc7bf 100644
--- a/drivers/net/ethernet/broadcom/bcm63xx_enet.c
+++ b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
@@ -1192,7 +1192,6 @@ static int bcm_enet_stop(struct net_device *dev)
kdev = &priv->pdev->dev;
 
netif_stop_queue(dev);
-   netdev_reset_queue(dev);
napi_disable(&priv->napi);
if (priv->has_phy)
phy_stop(dev->phydev);
@@ -1231,6 +1230,9 @@ static int bcm_enet_stop(struct net_device *dev)
if (priv->has_phy)
phy_disconnect(dev->phydev);
 
+   /* reset BQL after forced tx reclaim to prevent kernel panic */
+   netdev_reset_queue(dev);
+
return 0;
 }
 
@@ -2343,7 +2345,6 @@ static int bcm_enetsw_stop(struct net_device *dev)
 
del_timer_sync(&priv->swphy_poll);
netif_stop_queue(dev);
-   netdev_reset_queue(dev);
napi_disable(&priv->napi);
del_timer_sync(&priv->rx_timeout);
 
@@ -2371,6 +2372,9 @@ static int bcm_enetsw_stop(struct net_device *dev)
free_irq(priv->irq_tx, dev);
free_irq(priv->irq_rx, dev);
 
+   /* reset BQL after forced tx reclaim to prevent kernel panic */
+   netdev_reset_queue(dev);
+
return 0;
 }
 
-- 
2.17.1