drivers/net/usb/asix_devices.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
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;
}
--
2.34.1On 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
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
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
> > > 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
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
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