[PATCH] net: allwinner: emac: Add missing free_irq

[PATCH] net: allwinner: emac: Add missing free_irq

[Maxime Ripard]

The sun4i-emac driver uses devm_request_irq at .ndo_open time, but relies on
the managed device mechanism to actually free it. This causes an issue whenever
someone wants to restart the interface, the interrupt still being held, and not
yet released.

Fall back to using the regular request_irq at .ndo_open time, and introduce a
free_irq during .ndo_stop.

Signed-off-by: Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
---
Hi David,

It would be great if this patch would be applied to 3.13.

Thanks,
Maxime


 drivers/net/ethernet/allwinner/sun4i-emac.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
index 50b853a..38aba50 100644
--- a/drivers/net/ethernet/allwinner/sun4i-emac.c
+++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
@@ -717,8 +717,8 @@ static int emac_open(struct net_device *dev)
 	if (netif_msg_ifup(db))
 		dev_dbg(db->dev, "enabling %s\n", dev->name);
 
-	if (devm_request_irq(db->dev, dev->irq, &emac_interrupt,
-			     0, dev->name, dev))
+	if (request_irq(dev->irq, &emac_interrupt,
+			0, dev->name, dev))
 		return -EAGAIN;
 
 	/* Initialize EMAC board */
@@ -774,6 +774,8 @@ static int emac_stop(struct net_device *ndev)
 
 	emac_shutdown(ndev);
 
+	free_irq(ndev->irq, ndev);
+
 	return 0;
 }
 
-- 
1.8.4.2

Re: [PATCH] net: allwinner: emac: Add missing free_irq

[Sergei Shtylyov]

Hello.

On 07-12-2013 15:31, Maxime Ripard wrote:

> The sun4i-emac driver uses devm_request_irq at .ndo_open time, but relies on
> the managed device mechanism to actually free it. This causes an issue whenever
> someone wants to restart the interface, the interrupt still being held, and not
> yet released.

> Fall back to using the regular request_irq at .ndo_open time, and introduce a
> free_irq during .ndo_stop.

> Signed-off-by: Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> ---
> Hi David,

> It would be great if this patch would be applied to 3.13.

> Thanks,
> Maxime


>   drivers/net/ethernet/allwinner/sun4i-emac.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)

> diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
> index 50b853a..38aba50 100644
> --- a/drivers/net/ethernet/allwinner/sun4i-emac.c
> +++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
> @@ -717,8 +717,8 @@ static int emac_open(struct net_device *dev)
>   	if (netif_msg_ifup(db))
>   		dev_dbg(db->dev, "enabling %s\n", dev->name);
>
> -	if (devm_request_irq(db->dev, dev->irq, &emac_interrupt,
> -			     0, dev->name, dev))
> +	if (request_irq(dev->irq, &emac_interrupt,
> +			0, dev->name, dev))

    Doesn't it fit into single line?

WBR, Sergei

Re: [PATCH] net: allwinner: emac: Add missing free_irq

[Maxime Ripard]

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Hi,

On Sat, Dec 07, 2013 at 08:57:05PM +0400, Sergei Shtylyov wrote:
> Hello.
> 
> On 07-12-2013 15:31, Maxime Ripard wrote:
> 
> >The sun4i-emac driver uses devm_request_irq at .ndo_open time, but relies on
> >the managed device mechanism to actually free it. This causes an issue whenever
> >someone wants to restart the interface, the interrupt still being held, and not
> >yet released.
> 
> >Fall back to using the regular request_irq at .ndo_open time, and introduce a
> >free_irq during .ndo_stop.
> 
> >Signed-off-by: Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> >---
> >Hi David,
> 
> >It would be great if this patch would be applied to 3.13.
> 
> >Thanks,
> >Maxime
> 
> 
> >  drivers/net/ethernet/allwinner/sun4i-emac.c | 6 ++++--
> >  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> >diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
> >index 50b853a..38aba50 100644
> >--- a/drivers/net/ethernet/allwinner/sun4i-emac.c
> >+++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
> >@@ -717,8 +717,8 @@ static int emac_open(struct net_device *dev)
> >  	if (netif_msg_ifup(db))
> >  		dev_dbg(db->dev, "enabling %s\n", dev->name);
> >
> >-	if (devm_request_irq(db->dev, dev->irq, &emac_interrupt,
> >-			     0, dev->name, dev))
> >+	if (request_irq(dev->irq, &emac_interrupt,
> >+			0, dev->name, dev))
> 
>    Doesn't it fit into single line?

Hmmm, yes, probably.

I'll send a v2.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

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[PATCH] net: allwinner: emac: Add missing free_irq

[Maxime Ripard]

If the mdio probe function fails in emac_open, the interrupt we just requested
isn't freed. If emac_open is called again, for example because we try to set up
the interface again, the kernel will oops because the interrupt wasn't properly
released.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: <stable@vger.kernel.org> # 3.11+
---
 drivers/net/ethernet/allwinner/sun4i-emac.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
index 28460676b8ca..d81e7167a8b5 100644
--- a/drivers/net/ethernet/allwinner/sun4i-emac.c
+++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
@@ -736,6 +736,7 @@ static int emac_open(struct net_device *dev)
 
 	ret = emac_mdio_probe(dev);
 	if (ret < 0) {
+		free_irq(dev->irq, dev);
 		netdev_err(dev, "cannot probe MDIO bus\n");
 		return ret;
 	}
-- 
2.0.0

Re: [PATCH] net: allwinner: emac: Add missing free_irq

[David Miller]

From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Mon, 23 Jun 2014 22:49:40 +0200

> If the mdio probe function fails in emac_open, the interrupt we just requested
> isn't freed. If emac_open is called again, for example because we try to set up
> the interface again, the kernel will oops because the interrupt wasn't properly
> released.
> 
> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> Cc: <stable@vger.kernel.org> # 3.11+

Applied, thank you.