| Message ID | 20161212193752.32029-1-grygorii.strashko@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Grygorii Strashko <grygorii.strashko@ti.com> [161212 11:38]: > Now races can happen between interrupt handler execution and PM runtime in > error handling code path in probe and in dwc3_omap_remove() which will lead > to system crash: > > in probe: > ... > err1: > pm_runtime_put_sync(dev); > ^^ PM runtime can race with IRQ handler when deferred probing happening > due to extcon > pm_runtime_disable(dev); > > return ret; > > in dwc3_omap_remove: > ... > dwc3_omap_disable_irqs(omap); > ^^ IRQs are disabled in HW, but handler may still run > of_platform_depopulate(omap->dev); > pm_runtime_put_sync(&pdev->dev); > ^^ PM runtime can race with IRQ handler > pm_runtime_disable(&pdev->dev); > > return 0; > > So, OMAP DWC3 IRQ need to be disabled before calling > pm_runtime_put() in probe and in dwc3_omap_remove(). Acked-by: Tony Lindgren <tony@atomide.com>
diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c index 29e80cc..eb1b9cb 100644 --- a/drivers/usb/dwc3/dwc3-omap.c +++ b/drivers/usb/dwc3/dwc3-omap.c @@ -19,6 +19,7 @@ #include <linux/module.h> #include <linux/kernel.h> #include <linux/slab.h> +#include <linux/irq.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/platform_data/dwc3-omap.h> @@ -510,7 +511,7 @@ static int dwc3_omap_probe(struct platform_device *pdev) /* check the DMA Status */ reg = dwc3_omap_readl(omap->base, USBOTGSS_SYSCONFIG); - + irq_set_status_flags(omap->irq, IRQ_NOAUTOEN); ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt, dwc3_omap_interrupt_thread, IRQF_SHARED, "dwc3-omap", omap); @@ -531,7 +532,7 @@ static int dwc3_omap_probe(struct platform_device *pdev) } dwc3_omap_enable_irqs(omap); - + enable_irq(omap->irq); return 0; err2: @@ -552,6 +553,7 @@ static int dwc3_omap_remove(struct platform_device *pdev) extcon_unregister_notifier(omap->edev, EXTCON_USB, &omap->vbus_nb); extcon_unregister_notifier(omap->edev, EXTCON_USB_HOST, &omap->id_nb); dwc3_omap_disable_irqs(omap); + disable_irq(omap->irq); of_platform_depopulate(omap->dev); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev);
Now races can happen between interrupt handler execution and PM runtime in error handling code path in probe and in dwc3_omap_remove() which will lead to system crash: in probe: ... err1: pm_runtime_put_sync(dev); ^^ PM runtime can race with IRQ handler when deferred probing happening due to extcon pm_runtime_disable(dev); return ret; in dwc3_omap_remove: ... dwc3_omap_disable_irqs(omap); ^^ IRQs are disabled in HW, but handler may still run of_platform_depopulate(omap->dev); pm_runtime_put_sync(&pdev->dev); ^^ PM runtime can race with IRQ handler pm_runtime_disable(&pdev->dev); return 0; So, OMAP DWC3 IRQ need to be disabled before calling pm_runtime_put() in probe and in dwc3_omap_remove(). Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> --- Link on v1: http://www.spinics.net/lists/linux-omap/msg133846.html drivers/usb/dwc3/dwc3-omap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)