imx.lists.linux.dev archive mirror
 help / color / mirror / Atom feed
* [PATCH] net: usb: asix: avoid to call phylink_stop() a second time
@ 2025-08-06  8:30 Xu Yang
  2025-08-06 15:58 ` Andrew Lunn
  0 siblings, 1 reply; 6+ messages in thread
From: Xu Yang @ 2025-08-06  8:30 UTC (permalink / raw)
  To: andrew+netdev, davem, edumazet, kuba, pabeni, max.schulze,
	khalasa, o.rempel
  Cc: linux-usb, netdev, linux-kernel, imx, jun.li

The kernel will have below dump when system resume if the USB net device
was already disconnected during system suspend.

[   46.392207] ------------[ cut here ]------------
[   46.392216] called from state HALTED
[   46.392255] WARNING: CPU: 0 PID: 56 at drivers/net/phy/phy.c:1630 phy_stop+0x12c/0x194
[   46.392272] Modules linked in:
[   46.392281] CPU: 0 UID: 0 PID: 56 Comm: kworker/0:3 Not tainted 6.15.0-rc7-next-20250523-06664-ga6888feb9f45-dirty #311 PREEMPT
[   46.392287] Hardware name: NXP i.MX93 11X11 EVK board (DT)
[   46.392291] Workqueue: usb_hub_wq hub_event
[   46.392301] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   46.392306] pc : phy_stop+0x12c/0x194
[   46.392311] lr : phy_stop+0x12c/0x194
[   46.392315] sp : ffff8000828fb720
[   46.392317] x29: ffff8000828fb720 x28: ffff000005558b50 x27: ffff00000555b400
[   46.392324] x26: ffff000004e4f000 x25: ffff00000557f800 x24: 0000000000000000
[   46.392331] x23: 0000000000000000 x22: ffff8000817eea10 x21: ffff000004fc5000
[   46.392338] x20: ffff000004fc5a00 x19: ffff0000056eb000 x18: fffffffffffeb3c0
[   46.392345] x17: ffff7ffffdc3c000 x16: ffff800080000000 x15: 0000000000000000
[   46.392352] x14: 0000000000000000 x13: 206574617473206d x12: ffff800082057068
[   46.392359] x11: 0000000000000058 x10: 0000000000000018 x9 : ffff800082057068
[   46.392366] x8 : 0000000000000264 x7 : ffff8000820af068 x6 : ffff8000820af068
[   46.392373] x5 : ffff00007fb80308 x4 : 0000000000000000 x3 : ffff7ffffdc3c000
[   46.392379] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000004ed4600
[   46.392386] Call trace:
[   46.392390]  phy_stop+0x12c/0x194 (P)
[   46.392396]  phylink_stop+0x28/0x114
[   46.392404]  ax88772_stop+0x18/0x28
[   46.392411]  usbnet_stop+0x80/0x230
[   46.392418]  __dev_close_many+0xb4/0x1e0
[   46.392427]  dev_close_many+0x88/0x140
[   46.392434]  unregister_netdevice_many_notify+0x1b8/0xa10
[   46.392440]  unregister_netdevice_queue+0xe0/0xe8
[   46.392445]  unregister_netdev+0x24/0x50
[   46.392450]  usbnet_disconnect+0x50/0x124
[   46.392457]  usb_unbind_interface+0x78/0x2b4
[   46.392463]  device_remove+0x70/0x80
[   46.392470]  device_release_driver_internal+0x1cc/0x224
[   46.392475]  device_release_driver+0x18/0x30
[   46.392480]  bus_remove_device+0xc8/0x108
[   46.392488]  device_del+0x14c/0x420
[   46.392495]  usb_disable_device+0xe4/0x1c0
[   46.392502]  usb_disconnect+0xd8/0x2ac
[   46.392508]  hub_event+0x91c/0x1580
[   46.392514]  process_one_work+0x148/0x290
[   46.392523]  worker_thread+0x2c8/0x3e4
[   46.392530]  kthread+0x12c/0x204
[   46.392536]  ret_from_fork+0x10/0x20
[   46.392545] ---[ end trace 0000000000000000 ]---

It's because usb_resume_interface() will be skipped if the USB core found
the USB device was already disconnected. In this case, asix_resume() will
not be called anymore. So asix_suspend/resume() can't be balanced. When
ax88772_stop() is called, the phy device was already stopped. To avoid
calling phylink_stop() a second time, check whether usb net device is
already in suspend state.

Fixes: e0bffe3e6894 ("net: asix: ax88772: migrate to phylink")
Cc: stable@vger.kernel.org
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
---
 drivers/net/usb/asix_devices.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index 9b0318fb50b5..ac28f5fe7ac2 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -932,7 +932,8 @@ static int ax88772_stop(struct usbnet *dev)
 {
 	struct asix_common_private *priv = dev->driver_priv;
 
-	phylink_stop(priv->phylink);
+	if (!dev->suspend_count)
+		phylink_stop(priv->phylink);
 
 	return 0;
 }
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] net: usb: asix: avoid to call phylink_stop() a second time
  2025-08-06  8:30 [PATCH] net: usb: asix: avoid to call phylink_stop() a second time Xu Yang
@ 2025-08-06 15:58 ` Andrew Lunn
  2025-08-07  4:03   ` Xu Yang
  0 siblings, 1 reply; 6+ messages in thread
From: Andrew Lunn @ 2025-08-06 15:58 UTC (permalink / raw)
  To: Xu Yang
  Cc: andrew+netdev, davem, edumazet, kuba, pabeni, max.schulze,
	khalasa, o.rempel, linux-usb, netdev, linux-kernel, imx, jun.li

On Wed, Aug 06, 2025 at 04:30:17PM +0800, Xu Yang wrote:
> The kernel will have below dump when system resume if the USB net device
> was already disconnected during system suspend.

By disconnected, you mean pulled out?

> It's because usb_resume_interface() will be skipped if the USB core found
> the USB device was already disconnected. In this case, asix_resume() will
> not be called anymore. So asix_suspend/resume() can't be balanced. When
> ax88772_stop() is called, the phy device was already stopped. To avoid
> calling phylink_stop() a second time, check whether usb net device is
> already in suspend state.
> 
> Fixes: e0bffe3e6894 ("net: asix: ax88772: migrate to phylink")
> Cc: stable@vger.kernel.org
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> ---
>  drivers/net/usb/asix_devices.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> index 9b0318fb50b5..ac28f5fe7ac2 100644
> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -932,7 +932,8 @@ static int ax88772_stop(struct usbnet *dev)
>  {
>  	struct asix_common_private *priv = dev->driver_priv;
>  
> -	phylink_stop(priv->phylink);
> +	if (!dev->suspend_count)
> +		phylink_stop(priv->phylink);

Looking at ax88172a.c, lan78xx.c and smsc95xx.c, they don't have
anything like this. Is asix special, or are all the others broken as
well?

	Andrew

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] net: usb: asix: avoid to call phylink_stop() a second time
  2025-08-06 15:58 ` Andrew Lunn
@ 2025-08-07  4:03   ` Xu Yang
  2025-08-15  8:15     ` Xu Yang
  0 siblings, 1 reply; 6+ messages in thread
From: Xu Yang @ 2025-08-07  4:03 UTC (permalink / raw)
  To: Andrew Lunn
  Cc: andrew+netdev, davem, edumazet, kuba, pabeni, max.schulze,
	khalasa, o.rempel, linux-usb, netdev, linux-kernel, imx, jun.li

Hi Andrew,

Thanks for your comments!

On Wed, Aug 06, 2025 at 05:58:18PM +0200, Andrew Lunn wrote:
> On Wed, Aug 06, 2025 at 04:30:17PM +0800, Xu Yang wrote:
> > The kernel will have below dump when system resume if the USB net device
> > was already disconnected during system suspend.
> 
> By disconnected, you mean pulled out?

Yes.

> 
> > It's because usb_resume_interface() will be skipped if the USB core found
> > the USB device was already disconnected. In this case, asix_resume() will
> > not be called anymore. So asix_suspend/resume() can't be balanced. When
> > ax88772_stop() is called, the phy device was already stopped. To avoid
> > calling phylink_stop() a second time, check whether usb net device is
> > already in suspend state.
> > 
> > Fixes: e0bffe3e6894 ("net: asix: ax88772: migrate to phylink")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> > ---
> >  drivers/net/usb/asix_devices.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> > index 9b0318fb50b5..ac28f5fe7ac2 100644
> > --- a/drivers/net/usb/asix_devices.c
> > +++ b/drivers/net/usb/asix_devices.c
> > @@ -932,7 +932,8 @@ static int ax88772_stop(struct usbnet *dev)
> >  {
> >  	struct asix_common_private *priv = dev->driver_priv;
> >  
> > -	phylink_stop(priv->phylink);
> > +	if (!dev->suspend_count)
> > +		phylink_stop(priv->phylink);
> 
> Looking at ax88172a.c, lan78xx.c and smsc95xx.c, they don't have
> anything like this. Is asix special, or are all the others broken as
> well?

I have limited USB net devices. So I can't test others now.

But based on the error path, only below driver call phy_stop() or phylink_stop()
in their stop() callback:

drivers/net/usb/asix_devices.c
  ax88772_stop()
    phylink_stop()

drivers/net/usb/ax88172a.c
  ax88172a_stop()
    phy_stop()

drivers/net/usb/lan78xx.c
  lan78xx_stop()
    phylink_stop()

drivers/net/usb/smsc95xx.c
  smsc95xx_stop()
    phy_stop()

However, only asix_devices.c and lan78xx.c call phylink_suspend() in suspend()
callback. So I think lan78xx.c has this issue too.

Should I change usbnet common code like below?

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index c39dfa17813a..44a8d325dfb1 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -839,7 +839,7 @@ int usbnet_stop (struct net_device *net)
        pm = usb_autopm_get_interface(dev->intf);
        /* allow minidriver to stop correctly (wireless devices to turn off
         * radio etc) */
-       if (info->stop) {
+       if (info->stop && !dev->suspend_count) {
                retval = info->stop(dev);
                if (retval < 0)
                        netif_info(dev, ifdown, dev->net,

Thanks,
Xu Yang

> 
> 	Andrew

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] net: usb: asix: avoid to call phylink_stop() a second time
  2025-08-07  4:03   ` Xu Yang
@ 2025-08-15  8:15     ` Xu Yang
  2025-08-15 12:59       ` Andrew Lunn
  0 siblings, 1 reply; 6+ messages in thread
From: Xu Yang @ 2025-08-15  8:15 UTC (permalink / raw)
  To: Andrew Lunn
  Cc: andrew+netdev, davem, edumazet, kuba, pabeni, max.schulze,
	khalasa, o.rempel, linux-usb, netdev, linux-kernel, imx, jun.li

On Thu, Aug 07, 2025 at 12:03:39PM +0800, Xu Yang wrote:
> Hi Andrew,
> 
> Thanks for your comments!
> 
> On Wed, Aug 06, 2025 at 05:58:18PM +0200, Andrew Lunn wrote:
> > On Wed, Aug 06, 2025 at 04:30:17PM +0800, Xu Yang wrote:
> > > The kernel will have below dump when system resume if the USB net device
> > > was already disconnected during system suspend.
> > 
> > By disconnected, you mean pulled out?
> 
> Yes.
> 
> > 
> > > It's because usb_resume_interface() will be skipped if the USB core found
> > > the USB device was already disconnected. In this case, asix_resume() will
> > > not be called anymore. So asix_suspend/resume() can't be balanced. When
> > > ax88772_stop() is called, the phy device was already stopped. To avoid
> > > calling phylink_stop() a second time, check whether usb net device is
> > > already in suspend state.
> > > 
> > > Fixes: e0bffe3e6894 ("net: asix: ax88772: migrate to phylink")
> > > Cc: stable@vger.kernel.org
> > > Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> > > ---
> > >  drivers/net/usb/asix_devices.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> > > index 9b0318fb50b5..ac28f5fe7ac2 100644
> > > --- a/drivers/net/usb/asix_devices.c
> > > +++ b/drivers/net/usb/asix_devices.c
> > > @@ -932,7 +932,8 @@ static int ax88772_stop(struct usbnet *dev)
> > >  {
> > >  	struct asix_common_private *priv = dev->driver_priv;
> > >  
> > > -	phylink_stop(priv->phylink);
> > > +	if (!dev->suspend_count)
> > > +		phylink_stop(priv->phylink);
> > 
> > Looking at ax88172a.c, lan78xx.c and smsc95xx.c, they don't have
> > anything like this. Is asix special, or are all the others broken as
> > well?
> 
> I have limited USB net devices. So I can't test others now.
> 
> But based on the error path, only below driver call phy_stop() or phylink_stop()
> in their stop() callback:
> 
> drivers/net/usb/asix_devices.c
>   ax88772_stop()
>     phylink_stop()
> 
> drivers/net/usb/ax88172a.c
>   ax88172a_stop()
>     phy_stop()
> 
> drivers/net/usb/lan78xx.c
>   lan78xx_stop()
>     phylink_stop()
> 
> drivers/net/usb/smsc95xx.c
>   smsc95xx_stop()
>     phy_stop()
> 
> However, only asix_devices.c and lan78xx.c call phylink_suspend() in suspend()
> callback. So I think lan78xx.c has this issue too.
> 
> Should I change usbnet common code like below?
> 
> diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
> index c39dfa17813a..44a8d325dfb1 100644
> --- a/drivers/net/usb/usbnet.c
> +++ b/drivers/net/usb/usbnet.c
> @@ -839,7 +839,7 @@ int usbnet_stop (struct net_device *net)
>         pm = usb_autopm_get_interface(dev->intf);
>         /* allow minidriver to stop correctly (wireless devices to turn off
>          * radio etc) */
> -       if (info->stop) {
> +       if (info->stop && !dev->suspend_count) {
>                 retval = info->stop(dev);
>                 if (retval < 0)
>                         netif_info(dev, ifdown, dev->net,

Do you mind sharing some suggestions on this? Thanks in advance!

Thanks,
Xu Yang

> 
> Thanks,
> Xu Yang
> 
> > 
> > 	Andrew

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] net: usb: asix: avoid to call phylink_stop() a second time
  2025-08-15  8:15     ` Xu Yang
@ 2025-08-15 12:59       ` Andrew Lunn
  2025-08-18  6:44         ` Xu Yang
  0 siblings, 1 reply; 6+ messages in thread
From: Andrew Lunn @ 2025-08-15 12:59 UTC (permalink / raw)
  To: Xu Yang
  Cc: andrew+netdev, davem, edumazet, kuba, pabeni, max.schulze,
	khalasa, o.rempel, linux-usb, netdev, linux-kernel, imx, jun.li

> > > Looking at ax88172a.c, lan78xx.c and smsc95xx.c, they don't have
> > > anything like this. Is asix special, or are all the others broken as
> > > well?
> > 
> > I have limited USB net devices. So I can't test others now.
> > 
> > But based on the error path, only below driver call phy_stop() or phylink_stop()
> > in their stop() callback:
> > 
> > drivers/net/usb/asix_devices.c
> >   ax88772_stop()
> >     phylink_stop()
> > 
> > drivers/net/usb/ax88172a.c
> >   ax88172a_stop()
> >     phy_stop()
> > 
> > drivers/net/usb/lan78xx.c
> >   lan78xx_stop()
> >     phylink_stop()
> > 
> > drivers/net/usb/smsc95xx.c
> >   smsc95xx_stop()
> >     phy_stop()
> > 
> > However, only asix_devices.c and lan78xx.c call phylink_suspend() in suspend()
> > callback. So I think lan78xx.c has this issue too.
> > 
> > Should I change usbnet common code like below?
> > 
> > diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
> > index c39dfa17813a..44a8d325dfb1 100644
> > --- a/drivers/net/usb/usbnet.c
> > +++ b/drivers/net/usb/usbnet.c
> > @@ -839,7 +839,7 @@ int usbnet_stop (struct net_device *net)
> >         pm = usb_autopm_get_interface(dev->intf);
> >         /* allow minidriver to stop correctly (wireless devices to turn off
> >          * radio etc) */
> > -       if (info->stop) {
> > +       if (info->stop && !dev->suspend_count) {
> >                 retval = info->stop(dev);
> >                 if (retval < 0)
> >                         netif_info(dev, ifdown, dev->net,
> 
> Do you mind sharing some suggestions on this? Thanks in advance!

It does look to be a common problem, so solving it in usbnet would be
best.

	Andrew

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] net: usb: asix: avoid to call phylink_stop() a second time
  2025-08-15 12:59       ` Andrew Lunn
@ 2025-08-18  6:44         ` Xu Yang
  0 siblings, 0 replies; 6+ messages in thread
From: Xu Yang @ 2025-08-18  6:44 UTC (permalink / raw)
  To: Andrew Lunn
  Cc: andrew+netdev, davem, edumazet, kuba, pabeni, max.schulze,
	khalasa, o.rempel, linux-usb, netdev, linux-kernel, imx, jun.li

On Fri, Aug 15, 2025 at 02:59:12PM +0200, Andrew Lunn wrote:
> > > > Looking at ax88172a.c, lan78xx.c and smsc95xx.c, they don't have
> > > > anything like this. Is asix special, or are all the others broken as
> > > > well?
> > > 
> > > I have limited USB net devices. So I can't test others now.
> > > 

[...]

> > > 
> > > Should I change usbnet common code like below?
> > > 
> > > diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
> > > index c39dfa17813a..44a8d325dfb1 100644
> > > --- a/drivers/net/usb/usbnet.c
> > > +++ b/drivers/net/usb/usbnet.c
> > > @@ -839,7 +839,7 @@ int usbnet_stop (struct net_device *net)
> > >         pm = usb_autopm_get_interface(dev->intf);
> > >         /* allow minidriver to stop correctly (wireless devices to turn off
> > >          * radio etc) */
> > > -       if (info->stop) {
> > > +       if (info->stop && !dev->suspend_count) {
> > >                 retval = info->stop(dev);
> > >                 if (retval < 0)
> > >                         netif_info(dev, ifdown, dev->net,
> > 
> > Do you mind sharing some suggestions on this? Thanks in advance!
> 
> It does look to be a common problem, so solving it in usbnet would be
> best.

Okay. Thank you!

Thanks,
Xu Yang

> 
> 	Andrew

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2025-08-18  6:49 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-08-06  8:30 [PATCH] net: usb: asix: avoid to call phylink_stop() a second time Xu Yang
2025-08-06 15:58 ` Andrew Lunn
2025-08-07  4:03   ` Xu Yang
2025-08-15  8:15     ` Xu Yang
2025-08-15 12:59       ` Andrew Lunn
2025-08-18  6:44         ` Xu Yang

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).