diff mbox series

[net] bcm63xx_enet: fix sporadic kernel panic

Message ID 20210222013530.1356-1-liew.s.piaw@gmail.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series [net] bcm63xx_enet: fix sporadic kernel panic | expand

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Context Check Description
netdev/cover_letter success Link
netdev/fixes_present fail Series targets non-next tree, but doesn't contain any Fixes tags
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net
netdev/subject_prefix success Link
netdev/cc_maintainers warning 2 maintainers not CCed: leon@kernel.org tangbin@cmss.chinamobile.com
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 32 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Sieng-Piaw Liew Feb. 22, 2021, 1:35 a.m. UTC
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 <liew.s.piaw@gmail.com>
---
 drivers/net/ethernet/broadcom/bcm63xx_enet.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

Comments

Florian Fainelli Feb. 22, 2021, 5:05 a.m. UTC | #1
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 <liew.s.piaw@gmail.com>

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Fixes: 4c59b0f5543d ("bcm63xx_enet: add BQL support")
Jakub Kicinski Feb. 23, 2021, 8:16 p.m. UTC | #2
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 <liew.s.piaw@gmail.com>  
> 
> Acked-by: Florian Fainelli <f.fainelli@gmail.com>
> Fixes: 4c59b0f5543d ("bcm63xx_enet: add BQL support")

Applied, thanks!
diff mbox series

Patch

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;
 }