Re: [PATCH 1/1] usb: cdns3: Put the cdns set active part outside the spin lock

[wang xiaolei <xiaolei.wang@windriver.com>]

On 6/15/23 8:49 PM, Greg KH wrote:
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> On Wed, Jun 14, 2023 at 11:16:05AM +0800, wangxiaolei wrote:
>> On 5/5/23 6:33 PM, Greg KH wrote:
>>> CAUTION: This email comes from a non Wind River email account!
>>> Do not click links or open attachments unless you recognize the sender and know the content is safe.
>>>
>>> On Thu, May 04, 2023 at 09:16:02PM +0800, Xiaolei Wang wrote:
>>>> The device may be scheduled during the resume process,
>>>> so this cannot appear in atomic operations. Since
>>>> pm_runtime_set_active will resume suppliers, put set
>>>> active outside the spin lock, which is only used to
>>>> protect the struct cdns data structure, otherwise the
>>>> kernel will report the following warning:
>>>>
>>>>     BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1163
>>>>     in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 651, name: sh
>>>>     preempt_count: 1, expected: 0
>>>>     RCU nest depth: 0, expected: 0
>>>>     CPU: 0 PID: 651 Comm: sh Tainted: G        WC         6.1.20 #1
>>>>     Hardware name: Freescale i.MX8QM MEK (DT)
>>>>     Call trace:
>>>>       dump_backtrace.part.0+0xe0/0xf0
>>>>       show_stack+0x18/0x30
>>>>       dump_stack_lvl+0x64/0x80
>>>>       dump_stack+0x1c/0x38
>>>>       __might_resched+0x1fc/0x240
>>>>       __might_sleep+0x68/0xc0
>>>>       __pm_runtime_resume+0x9c/0xe0
>>>>       rpm_get_suppliers+0x68/0x1b0
>>>>       __pm_runtime_set_status+0x298/0x560
>>>>       cdns_resume+0xb0/0x1c0
>>>>       cdns3_controller_resume.isra.0+0x1e0/0x250
>>>>       cdns3_plat_resume+0x28/0x40
>>>>
>>>> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
>>>> ---
>>>>    drivers/usb/cdns3/cdns3-plat.c |  3 ++-
>>>>    drivers/usb/cdns3/cdnsp-pci.c  |  3 ++-
>>>>    drivers/usb/cdns3/core.c       | 14 +++++++++++---
>>>>    drivers/usb/cdns3/core.h       |  3 ++-
>>>>    4 files changed, 17 insertions(+), 6 deletions(-)
>>>>
>>>> diff --git a/drivers/usb/cdns3/cdns3-plat.c b/drivers/usb/cdns3/cdns3-plat.c
>>>> index 2bc5d094548b..726b2e4f67e4 100644
>>>> --- a/drivers/usb/cdns3/cdns3-plat.c
>>>> +++ b/drivers/usb/cdns3/cdns3-plat.c
>>>> @@ -256,9 +256,10 @@ static int cdns3_controller_resume(struct device *dev, pm_message_t msg)
>>>>         cdns3_set_platform_suspend(cdns->dev, false, false);
>>>>
>>>>         spin_lock_irqsave(&cdns->lock, flags);
>>>> -     cdns_resume(cdns, !PMSG_IS_AUTO(msg));
>>>> +     cdns_resume(cdns);
>>>>         cdns->in_lpm = false;
>>>>         spin_unlock_irqrestore(&cdns->lock, flags);
>>>> +     cdns_set_active(cdns, !PMSG_IS_AUTO(msg));
>>>>         if (cdns->wakeup_pending) {
>>>>                 cdns->wakeup_pending = false;
>>>>                 enable_irq(cdns->wakeup_irq);
>>>> diff --git a/drivers/usb/cdns3/cdnsp-pci.c b/drivers/usb/cdns3/cdnsp-pci.c
>>>> index 7b151f5af3cc..0725668ffea4 100644
>>>> --- a/drivers/usb/cdns3/cdnsp-pci.c
>>>> +++ b/drivers/usb/cdns3/cdnsp-pci.c
>>>> @@ -208,8 +208,9 @@ static int __maybe_unused cdnsp_pci_resume(struct device *dev)
>>>>         int ret;
>>>>
>>>>         spin_lock_irqsave(&cdns->lock, flags);
>>>> -     ret = cdns_resume(cdns, 1);
>>>> +     ret = cdns_resume(cdns);
>>>>         spin_unlock_irqrestore(&cdns->lock, flags);
>>>> +     cdns_set_active(cdns, 1);
>>>>
>>>>         return ret;
>>>>    }
>>>> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
>>>> index dbcdf3b24b47..661d5597fb68 100644
>>>> --- a/drivers/usb/cdns3/core.c
>>>> +++ b/drivers/usb/cdns3/core.c
>>>> @@ -522,7 +522,7 @@ int cdns_suspend(struct cdns *cdns)
>>>>    }
>>>>    EXPORT_SYMBOL_GPL(cdns_suspend);
>>>>
>>>> -int cdns_resume(struct cdns *cdns, u8 set_active)
>>>> +int cdns_resume(struct cdns *cdns)
>>>>    {
>>>>         struct device *dev = cdns->dev;
>>>>         enum usb_role real_role;
>>>> @@ -556,15 +556,23 @@ int cdns_resume(struct cdns *cdns, u8 set_active)
>>>>         if (cdns->roles[cdns->role]->resume)
>>>>                 cdns->roles[cdns->role]->resume(cdns, cdns_power_is_lost(cdns));
>>>>
>>>> +     return 0;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(cdns_resume);
>>>> +
>>>> +void cdns_set_active(struct cdns *cdns, u8 set_active)
>>>> +{
>>>> +     struct device *dev = cdns->dev;
>>>> +
>>>>         if (set_active) {
>>>>                 pm_runtime_disable(dev);
>>>>                 pm_runtime_set_active(dev);
>>>>                 pm_runtime_enable(dev);
>>>>         }
>>>>
>>>> -     return 0;
>>>> +     return;
>>>>    }
>>>> -EXPORT_SYMBOL_GPL(cdns_resume);
>>>> +EXPORT_SYMBOL_GPL(cdns_set_active);
>>>>    #endif /* CONFIG_PM_SLEEP */
>>>>
>>>>    MODULE_AUTHOR("Peter Chen <peter.chen@nxp.com>");
>>>> diff --git a/drivers/usb/cdns3/core.h b/drivers/usb/cdns3/core.h
>>>> index 2d332a788871..0f429042f997 100644
>>>> --- a/drivers/usb/cdns3/core.h
>>>> +++ b/drivers/usb/cdns3/core.h
>>>> @@ -125,8 +125,9 @@ int cdns_init(struct cdns *cdns);
>>>>    int cdns_remove(struct cdns *cdns);
>>>>
>>>>    #ifdef CONFIG_PM_SLEEP
>>>> -int cdns_resume(struct cdns *cdns, u8 set_active);
>>>> +int cdns_resume(struct cdns *cdns);
>>>>    int cdns_suspend(struct cdns *cdns);
>>>> +void cdns_set_active(struct cdns *cdns, u8 set_active);
>>>>    #else /* CONFIG_PM_SLEEP */
>>>>    static inline int cdns_resume(struct cdns *cdns, u8 set_active)
>>>>    { return 0; }
>>>> --
>>>> 2.25.1
>>>>
>>> Hi,
>>>
>>> This is the friendly semi-automated patch-bot of Greg Kroah-Hartman.
>>> You have sent him a patch that has triggered this response.
>>>
>>> Right now, the development tree you have sent a patch for is "closed"
>>> due to the timing of the merge window.  Don't worry, the patch(es) you
>>> have sent are not lost, and will be looked at after the merge window is
>>> over (after the -rc1 kernel is released by Linus).
>>>
>>> So thank you for your patience and your patches will be reviewed at this
>>> later time, you do not have to do anything further, this is just a short
>>> note to let you know the patch status and so you don't worry they didn't
>>> make it through.
>> Can someone help review this patch?
> It breaks the build:
>
> drivers/usb/cdns3/core.c: In function ‘cdns_resume’:
> drivers/usb/cdns3/core.c:527:24: error: unused variable ‘dev’ [-Werror=unused-variable]
>    527 |         struct device *dev = cdns->dev;
>        |                        ^~~
>
>
> How did you test it?

Oh, sorry, this may be because I did not set the compilation parameters,

which caused me to ignore this warning. I will delete the unused code 
and send the v2 version


thanks

xiaolei

>
> thanks,
>
> greg k-h