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

From: Greg KH
Date: Thu Jun 15 2023 - 05:50:31 EST


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@xxxxxxxxxxxxx>
> > > ---
> > > 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@xxxxxxx>");
> > > 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?

thanks,

greg k-h