| Message ID | 1413464285-24172-9-git-send-email-m.szyprowski@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On Thu, Oct 16, 2014 at 02:58:04PM +0200, Marek Szyprowski wrote: > This patch moves calls to phy enable/disable out of spinlock protected > blocks in device suspend/resume to fix incorrect caller context. Phy > related functions must not be called from atomic context. > > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> > --- > drivers/usb/dwc2/gadget.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c > index cdf417a7ae63..052b1a857291 100644 > --- a/drivers/usb/dwc2/gadget.c > +++ b/drivers/usb/dwc2/gadget.c > @@ -3656,11 +3656,13 @@ static int s3c_hsotg_suspend(struct platform_device *pdev, pm_message_t state) > hsotg->driver->driver.name); > > spin_lock_irqsave(&hsotg->lock, flags); > + s3c_hsotg_core_disconnect(hsotg); > s3c_hsotg_disconnect(hsotg); > - s3c_hsotg_phy_disable(hsotg); > hsotg->gadget.speed = USB_SPEED_UNKNOWN; > spin_unlock_irqrestore(&hsotg->lock, flags); > > + s3c_hsotg_phy_disable(hsotg); this is aching to have a locked version as well as an unlocked version. Look at what you do here. There's a minor race when you release that spinlock. By the time ->suspend() is called, IRQs are not yet disabled.
Hello, On 2014-10-16 15:42, Felipe Balbi wrote: > On Thu, Oct 16, 2014 at 02:58:04PM +0200, Marek Szyprowski wrote: >> This patch moves calls to phy enable/disable out of spinlock protected >> blocks in device suspend/resume to fix incorrect caller context. Phy >> related functions must not be called from atomic context. >> >> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> >> --- >> drivers/usb/dwc2/gadget.c | 9 ++++++--- >> 1 file changed, 6 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c >> index cdf417a7ae63..052b1a857291 100644 >> --- a/drivers/usb/dwc2/gadget.c >> +++ b/drivers/usb/dwc2/gadget.c >> @@ -3656,11 +3656,13 @@ static int s3c_hsotg_suspend(struct platform_device *pdev, pm_message_t state) >> hsotg->driver->driver.name); >> >> spin_lock_irqsave(&hsotg->lock, flags); >> + s3c_hsotg_core_disconnect(hsotg); >> s3c_hsotg_disconnect(hsotg); >> - s3c_hsotg_phy_disable(hsotg); >> hsotg->gadget.speed = USB_SPEED_UNKNOWN; >> spin_unlock_irqrestore(&hsotg->lock, flags); >> >> + s3c_hsotg_phy_disable(hsotg); > this is aching to have a locked version as well as an unlocked version. > Look at what you do here. There's a minor race when you release that > spinlock. By the time ->suspend() is called, IRQs are not yet disabled. s3c_hsotg_core_disconnect() disconnects the udc hardware from the usb bus, so even if the irq comes before s3c_hsotg_phy_disable(), nothing wrong happens, because the driver state is already set to disconnected. Best regards
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c index cdf417a7ae63..052b1a857291 100644 --- a/drivers/usb/dwc2/gadget.c +++ b/drivers/usb/dwc2/gadget.c @@ -3656,11 +3656,13 @@ static int s3c_hsotg_suspend(struct platform_device *pdev, pm_message_t state) hsotg->driver->driver.name); spin_lock_irqsave(&hsotg->lock, flags); + s3c_hsotg_core_disconnect(hsotg); s3c_hsotg_disconnect(hsotg); - s3c_hsotg_phy_disable(hsotg); hsotg->gadget.speed = USB_SPEED_UNKNOWN; spin_unlock_irqrestore(&hsotg->lock, flags); + s3c_hsotg_phy_disable(hsotg); + if (hsotg->driver) { int ep; for (ep = 0; ep < hsotg->num_of_eps; ep++) @@ -3689,9 +3691,10 @@ static int s3c_hsotg_resume(struct platform_device *pdev) hsotg->supplies); } - spin_lock_irqsave(&hsotg->lock, flags); s3c_hsotg_phy_enable(hsotg); - s3c_hsotg_core_init_disconnect(hsotg); + + spin_lock_irqsave(&hsotg->lock, flags); + s3c_hsotg_core_init_disconnected(hsotg); s3c_hsotg_core_connect(hsotg); spin_unlock_irqrestore(&hsotg->lock, flags);
This patch moves calls to phy enable/disable out of spinlock protected blocks in device suspend/resume to fix incorrect caller context. Phy related functions must not be called from atomic context. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- drivers/usb/dwc2/gadget.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)