* [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming
@ 2018-11-30 9:25 Kunihiko Hayashi
2018-11-30 17:46 ` Florian Fainelli
0 siblings, 1 reply; 5+ messages in thread
From: Kunihiko Hayashi @ 2018-11-30 9:25 UTC (permalink / raw)
To: Andrew Lunn, Florian Fainelli, Heiner Kallweit, David S. Miller
Cc: netdev, linux-kernel, Kunihiko Hayashi
Even though the link is down before entering hibernation,
there is an issue that the network interface always links up after resuming
from hibernation.
The phydev->state is PHY_READY before enabling the network interface, so
the link is down. After resuming from hibernation, the phydev->state is
forcibly set to PHY_UP in mdio_bus_phy_restore(), and the link becomes up.
This patch adds a new convenient function to check whether the PHY is in
a started state, and expects to solve the issue by changing phydev->state
to PHY_UP and calling phy_start_machine() only when the PHY is started.
Suggested-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
---
drivers/net/phy/phy.c | 2 +-
drivers/net/phy/phy_device.c | 9 +++++----
include/linux/phy.h | 10 ++++++++++
3 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 1d73ac3..f484d03 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -670,7 +670,7 @@ void phy_stop_machine(struct phy_device *phydev)
cancel_delayed_work_sync(&phydev->state_queue);
mutex_lock(&phydev->lock);
- if (phydev->state > PHY_UP && phydev->state != PHY_HALTED)
+ if (phy_is_started(phydev))
phydev->state = PHY_UP;
mutex_unlock(&phydev->lock);
}
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index ab33d17..2c39717 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -309,10 +309,11 @@ static int mdio_bus_phy_restore(struct device *dev)
return ret;
/* The PHY needs to renegotiate. */
- phydev->link = 0;
- phydev->state = PHY_UP;
-
- phy_start_machine(phydev);
+ if (phy_is_started(phydev)) {
+ phydev->link = 0;
+ phydev->state = PHY_UP;
+ phy_start_machine(phydev);
+ }
return 0;
}
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 3ea87f7..c194b45 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -898,6 +898,16 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
}
/**
+ * phy_is_started - Convenience function for testing whether a PHY is in
+ * a started state
+ * @phydev: the phy_device struct
+ */
+static inline bool phy_is_started(struct phy_device *phydev)
+{
+ return phydev->state >= PHY_UP && phydev->state != PHY_HALTED;
+}
+
+/**
* phy_write_mmd - Convenience function for writing a register
* on an MMD on a given PHY.
* @phydev: The phy_device struct
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming
2018-11-30 9:25 [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming Kunihiko Hayashi
@ 2018-11-30 17:46 ` Florian Fainelli
2018-11-30 18:47 ` Heiner Kallweit
0 siblings, 1 reply; 5+ messages in thread
From: Florian Fainelli @ 2018-11-30 17:46 UTC (permalink / raw)
To: Kunihiko Hayashi, Andrew Lunn, Heiner Kallweit, David S. Miller
Cc: netdev, linux-kernel
On 11/30/2018 1:25 AM, Kunihiko Hayashi wrote:
> Even though the link is down before entering hibernation,
> there is an issue that the network interface always links up after resuming
> from hibernation.
>
> The phydev->state is PHY_READY before enabling the network interface, so
> the link is down. After resuming from hibernation, the phydev->state is
> forcibly set to PHY_UP in mdio_bus_phy_restore(), and the link becomes up.
>
> This patch adds a new convenient function to check whether the PHY is in
> a started state, and expects to solve the issue by changing phydev->state
> to PHY_UP and calling phy_start_machine() only when the PHY is started.
>
> Suggested-by: Heiner Kallweit <hkallweit1@gmail.com>
> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> ---
> drivers/net/phy/phy.c | 2 +-
> drivers/net/phy/phy_device.c | 9 +++++----
> include/linux/phy.h | 10 ++++++++++
> 3 files changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index 1d73ac3..f484d03 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -670,7 +670,7 @@ void phy_stop_machine(struct phy_device *phydev)
> cancel_delayed_work_sync(&phydev->state_queue);
>
> mutex_lock(&phydev->lock);
> - if (phydev->state > PHY_UP && phydev->state != PHY_HALTED)
> + if (phy_is_started(phydev))
> phydev->state = PHY_UP;
> mutex_unlock(&phydev->lock);
> }
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index ab33d17..2c39717 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -309,10 +309,11 @@ static int mdio_bus_phy_restore(struct device *dev)
> return ret;
>
> /* The PHY needs to renegotiate. */
> - phydev->link = 0;
> - phydev->state = PHY_UP;
> -
> - phy_start_machine(phydev);
> + if (phy_is_started(phydev)) {
> + phydev->link = 0;
> + phydev->state = PHY_UP;
> + phy_start_machine(phydev);
> + }
Don't you need some of these steps to be performed under phydev->lock
being held? See comment below.
>
> return 0;
> }
> diff --git a/include/linux/phy.h b/include/linux/phy.h
> index 3ea87f7..c194b45 100644
> --- a/include/linux/phy.h
> +++ b/include/linux/phy.h
> @@ -898,6 +898,16 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
> }
>
> /**
> + * phy_is_started - Convenience function for testing whether a PHY is in
> + * a started state
> + * @phydev: the phy_device struct
> + */
> +static inline bool phy_is_started(struct phy_device *phydev)
> +{
An assert with the phydev->lock mutex being held here would greatly
help, because otherwise this is possibly racy.
> + return phydev->state >= PHY_UP && phydev->state != PHY_HALTED;
> +}
> +
> +/**
> * phy_write_mmd - Convenience function for writing a register
> * on an MMD on a given PHY.
> * @phydev: The phy_device struct
>
--
Florian
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming
2018-11-30 17:46 ` Florian Fainelli
@ 2018-11-30 18:47 ` Heiner Kallweit
2018-12-03 4:35 ` Kunihiko Hayashi
0 siblings, 1 reply; 5+ messages in thread
From: Heiner Kallweit @ 2018-11-30 18:47 UTC (permalink / raw)
To: Florian Fainelli, Kunihiko Hayashi, Andrew Lunn, David S. Miller
Cc: netdev, linux-kernel
On 30.11.2018 18:46, Florian Fainelli wrote:
>
>
> On 11/30/2018 1:25 AM, Kunihiko Hayashi wrote:
>> Even though the link is down before entering hibernation,
>> there is an issue that the network interface always links up after resuming
>> from hibernation.
>>
>> The phydev->state is PHY_READY before enabling the network interface, so
>> the link is down. After resuming from hibernation, the phydev->state is
>> forcibly set to PHY_UP in mdio_bus_phy_restore(), and the link becomes up.
>>
>> This patch adds a new convenient function to check whether the PHY is in
>> a started state, and expects to solve the issue by changing phydev->state
>> to PHY_UP and calling phy_start_machine() only when the PHY is started.
>>
>> Suggested-by: Heiner Kallweit <hkallweit1@gmail.com>
>> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
>> ---
>> drivers/net/phy/phy.c | 2 +-
>> drivers/net/phy/phy_device.c | 9 +++++----
>> include/linux/phy.h | 10 ++++++++++
>> 3 files changed, 16 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
>> index 1d73ac3..f484d03 100644
>> --- a/drivers/net/phy/phy.c
>> +++ b/drivers/net/phy/phy.c
>> @@ -670,7 +670,7 @@ void phy_stop_machine(struct phy_device *phydev)
>> cancel_delayed_work_sync(&phydev->state_queue);
>>
>> mutex_lock(&phydev->lock);
>> - if (phydev->state > PHY_UP && phydev->state != PHY_HALTED)
>> + if (phy_is_started(phydev))
>> phydev->state = PHY_UP;
>> mutex_unlock(&phydev->lock);
>> }
>> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
>> index ab33d17..2c39717 100644
>> --- a/drivers/net/phy/phy_device.c
>> +++ b/drivers/net/phy/phy_device.c
>> @@ -309,10 +309,11 @@ static int mdio_bus_phy_restore(struct device *dev)
>> return ret;
>>
>> /* The PHY needs to renegotiate. */
>> - phydev->link = 0;
>> - phydev->state = PHY_UP;
>> -
>> - phy_start_machine(phydev);
>> + if (phy_is_started(phydev)) {
>> + phydev->link = 0;
>> + phydev->state = PHY_UP;
>> + phy_start_machine(phydev);
>> + }
>
> Don't you need some of these steps to be performed under phydev->lock
> being held? See comment below.
>
Yes, locking should be done. The old code sets phydev->state
w/o holding the lock, I'd says this was wrong.
>>
>> return 0;
>> }
>> diff --git a/include/linux/phy.h b/include/linux/phy.h
>> index 3ea87f7..c194b45 100644
>> --- a/include/linux/phy.h
>> +++ b/include/linux/phy.h
>> @@ -898,6 +898,16 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
>> }
>>
>> /**
>> + * phy_is_started - Convenience function for testing whether a PHY is in
>> + * a started state
>> + * @phydev: the phy_device struct
>> + */
>> +static inline bool phy_is_started(struct phy_device *phydev)
>> +{
>
> An assert with the phydev->lock mutex being held here would greatly
> help, because otherwise this is possibly racy.
>
Have a look at __phy_resume() to see what is meant with this comment.
>> + return phydev->state >= PHY_UP && phydev->state != PHY_HALTED;
>> +}
>> +
>> +/**
>> * phy_write_mmd - Convenience function for writing a register
>> * on an MMD on a given PHY.
>> * @phydev: The phy_device struct
>>
>
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming
2018-11-30 18:47 ` Heiner Kallweit
@ 2018-12-03 4:35 ` Kunihiko Hayashi
2018-12-03 7:20 ` Heiner Kallweit
0 siblings, 1 reply; 5+ messages in thread
From: Kunihiko Hayashi @ 2018-12-03 4:35 UTC (permalink / raw)
To: Florian Fainelli, Heiner Kallweit
Cc: Andrew Lunn, David S. Miller, netdev, linux-kernel
Hi Florian Heiner,
On Fri, 30 Nov 2018 19:47:37 +0100 <hkallweit1@gmail.com> wrote:
> On 30.11.2018 18:46, Florian Fainelli wrote:
> >
> >
> > On 11/30/2018 1:25 AM, Kunihiko Hayashi wrote:
> >> Even though the link is down before entering hibernation,
> >> there is an issue that the network interface always links up after resuming
> >> from hibernation.
> >>
> >> The phydev->state is PHY_READY before enabling the network interface, so
> >> the link is down. After resuming from hibernation, the phydev->state is
> >> forcibly set to PHY_UP in mdio_bus_phy_restore(), and the link becomes up.
> >>
> >> This patch adds a new convenient function to check whether the PHY is in
> >> a started state, and expects to solve the issue by changing phydev->state
> >> to PHY_UP and calling phy_start_machine() only when the PHY is started.
> >>
> >> Suggested-by: Heiner Kallweit <hkallweit1@gmail.com>
> >> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> >> ---
> >> drivers/net/phy/phy.c | 2 +-
> >> drivers/net/phy/phy_device.c | 9 +++++----
> >> include/linux/phy.h | 10 ++++++++++
> >> 3 files changed, 16 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> >> index 1d73ac3..f484d03 100644
> >> --- a/drivers/net/phy/phy.c
> >> +++ b/drivers/net/phy/phy.c
> >> @@ -670,7 +670,7 @@ void phy_stop_machine(struct phy_device *phydev)
> >> cancel_delayed_work_sync(&phydev->state_queue);
> >>
> >> mutex_lock(&phydev->lock);
> >> - if (phydev->state > PHY_UP && phydev->state != PHY_HALTED)
> >> + if (phy_is_started(phydev))
> >> phydev->state = PHY_UP;
> >> mutex_unlock(&phydev->lock);
> >> }
> >> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> >> index ab33d17..2c39717 100644
> >> --- a/drivers/net/phy/phy_device.c
> >> +++ b/drivers/net/phy/phy_device.c
> >> @@ -309,10 +309,11 @@ static int mdio_bus_phy_restore(struct device *dev)
> >> return ret;
> >>
> >> /* The PHY needs to renegotiate. */
> >> - phydev->link = 0;
> >> - phydev->state = PHY_UP;
> >> -
> >> - phy_start_machine(phydev);
> >> + if (phy_is_started(phydev)) {
> >> + phydev->link = 0;
> >> + phydev->state = PHY_UP;
> >> + phy_start_machine(phydev);
> >> + }
> >
> > Don't you need some of these steps to be performed under phydev->lock
> > being held? See comment below.
> >
> Yes, locking should be done. The old code sets phydev->state
> w/o holding the lock, I'd says this was wrong.
Indeed. The phydev->state should be set with locking the mutex even here.
And it seems that setting phydev->link and calling phy_start_machine() don't
need to hold the lock. Is it correct?
> >>
> >> return 0;
> >> }
> >> diff --git a/include/linux/phy.h b/include/linux/phy.h
> >> index 3ea87f7..c194b45 100644
> >> --- a/include/linux/phy.h
> >> +++ b/include/linux/phy.h
> >> @@ -898,6 +898,16 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
> >> }
> >>
> >> /**
> >> + * phy_is_started - Convenience function for testing whether a PHY is in
> >> + * a started state
> >> + * @phydev: the phy_device struct
> >> + */
> >> +static inline bool phy_is_started(struct phy_device *phydev)
> >> +{
> >
> > An assert with the phydev->lock mutex being held here would greatly
> > help, because otherwise this is possibly racy.
> >
> Have a look at __phy_resume() to see what is meant with this comment.
I see. I found that there was a lock detection in this function.
The phy_is_started() should have the same detection, shouldn't it?
Thank you,
> >> + return phydev->state >= PHY_UP && phydev->state != PHY_HALTED;
> >> +}
> >> +
> >> +/**
> >> * phy_write_mmd - Convenience function for writing a register
> >> * on an MMD on a given PHY.
> >> * @phydev: The phy_device struct
> >>
> >
---
Best Regards,
Kunihiko Hayashi
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming
2018-12-03 4:35 ` Kunihiko Hayashi
@ 2018-12-03 7:20 ` Heiner Kallweit
0 siblings, 0 replies; 5+ messages in thread
From: Heiner Kallweit @ 2018-12-03 7:20 UTC (permalink / raw)
To: Kunihiko Hayashi, Florian Fainelli
Cc: Andrew Lunn, David S. Miller, netdev, linux-kernel
On 03.12.2018 05:35, Kunihiko Hayashi wrote:
> Hi Florian Heiner,
>
> On Fri, 30 Nov 2018 19:47:37 +0100 <hkallweit1@gmail.com> wrote:
>
>> On 30.11.2018 18:46, Florian Fainelli wrote:
>>>
>>>
>>> On 11/30/2018 1:25 AM, Kunihiko Hayashi wrote:
>>>> Even though the link is down before entering hibernation,
>>>> there is an issue that the network interface always links up after resuming
>>>> from hibernation.
>>>>
>>>> The phydev->state is PHY_READY before enabling the network interface, so
>>>> the link is down. After resuming from hibernation, the phydev->state is
>>>> forcibly set to PHY_UP in mdio_bus_phy_restore(), and the link becomes up.
>>>>
>>>> This patch adds a new convenient function to check whether the PHY is in
>>>> a started state, and expects to solve the issue by changing phydev->state
>>>> to PHY_UP and calling phy_start_machine() only when the PHY is started.
>>>>
>>>> Suggested-by: Heiner Kallweit <hkallweit1@gmail.com>
>>>> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
>>>> ---
>>>> drivers/net/phy/phy.c | 2 +-
>>>> drivers/net/phy/phy_device.c | 9 +++++----
>>>> include/linux/phy.h | 10 ++++++++++
>>>> 3 files changed, 16 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
>>>> index 1d73ac3..f484d03 100644
>>>> --- a/drivers/net/phy/phy.c
>>>> +++ b/drivers/net/phy/phy.c
>>>> @@ -670,7 +670,7 @@ void phy_stop_machine(struct phy_device *phydev)
>>>> cancel_delayed_work_sync(&phydev->state_queue);
>>>>
>>>> mutex_lock(&phydev->lock);
>>>> - if (phydev->state > PHY_UP && phydev->state != PHY_HALTED)
>>>> + if (phy_is_started(phydev))
>>>> phydev->state = PHY_UP;
>>>> mutex_unlock(&phydev->lock);
>>>> }
>>>> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
>>>> index ab33d17..2c39717 100644
>>>> --- a/drivers/net/phy/phy_device.c
>>>> +++ b/drivers/net/phy/phy_device.c
>>>> @@ -309,10 +309,11 @@ static int mdio_bus_phy_restore(struct device *dev)
>>>> return ret;
>>>>
>>>> /* The PHY needs to renegotiate. */
>>>> - phydev->link = 0;
>>>> - phydev->state = PHY_UP;
>>>> -
>>>> - phy_start_machine(phydev);
>>>> + if (phy_is_started(phydev)) {
>>>> + phydev->link = 0;
>>>> + phydev->state = PHY_UP;
>>>> + phy_start_machine(phydev);
>>>> + }
>>>
>>> Don't you need some of these steps to be performed under phydev->lock
>>> being held? See comment below.
>>>
>> Yes, locking should be done. The old code sets phydev->state
>> w/o holding the lock, I'd says this was wrong.
>
> Indeed. The phydev->state should be set with locking the mutex even here.
>
> And it seems that setting phydev->link and calling phy_start_machine() don't
> need to hold the lock. Is it correct?
>
Yes
>>>>
>>>> return 0;
>>>> }
>>>> diff --git a/include/linux/phy.h b/include/linux/phy.h
>>>> index 3ea87f7..c194b45 100644
>>>> --- a/include/linux/phy.h
>>>> +++ b/include/linux/phy.h
>>>> @@ -898,6 +898,16 @@ static inline bool phy_is_pseudo_fixed_link(struct phy_device *phydev)
>>>> }
>>>>
>>>> /**
>>>> + * phy_is_started - Convenience function for testing whether a PHY is in
>>>> + * a started state
>>>> + * @phydev: the phy_device struct
>>>> + */
>>>> +static inline bool phy_is_started(struct phy_device *phydev)
>>>> +{
>>>
>>> An assert with the phydev->lock mutex being held here would greatly
>>> help, because otherwise this is possibly racy.
>>>
>> Have a look at __phy_resume() to see what is meant with this comment.
>
> I see. I found that there was a lock detection in this function.
> The phy_is_started() should have the same detection, shouldn't it?
>
Correct
> Thank you,
>
>>>> + return phydev->state >= PHY_UP && phydev->state != PHY_HALTED;
>>>> +}
>>>> +
>>>> +/**
>>>> * phy_write_mmd - Convenience function for writing a register
>>>> * on an MMD on a given PHY.
>>>> * @phydev: The phy_device struct
>>>>
>>>
>
> ---
> Best Regards,
> Kunihiko Hayashi
>
Heiner
>
>
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-12-03 7:21 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-11-30 9:25 [RFC PATCH net v2] net: phy: Fix the issue that netif always links up after resuming Kunihiko Hayashi
2018-11-30 17:46 ` Florian Fainelli
2018-11-30 18:47 ` Heiner Kallweit
2018-12-03 4:35 ` Kunihiko Hayashi
2018-12-03 7:20 ` Heiner Kallweit
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).