On Wed, 24 Aug 2016, Peter Chen wrote:

> On Tue, Aug 23, 2016 at 09:17:02PM +0200, Stefan Wahren wrote:
> > Hi,
> > 
> > i'm using a iMX233-OLinuXino board and the kernel panics during shutdown 
> > with
> > 4.8.0-rc2-next-20160819:
> > 
> > [  420.040000] ci_hdrc ci_hdrc.0: remove, state 1
> > [  420.050000] usb usb1: USB disconnect, device number 1
> > [  420.060000] usb 1-1: USB disconnect, device number 2
> > [  420.060000] usb 1-1.1: USB disconnect, device number 3
> > [  420.090000] smsc95xx 1-1.1:1.0 eth0: unregister 'smsc95xx' 
> > usb-ci_hdrc.0-1.1,
> > smsc95xx USB 2.0 Ethernet
> > [  420.290000] ci_hdrc ci_hdrc.0: USB bus 1 deregistered
> > [  420.300000] Unable to handle kernel NULL pointer dereference at virtual
> > address 00000118
> > [  420.300000] pgd = c2ea4000
> > [  420.300000] [00000118] *pgd=00000000
> > [  420.300000] Internal error: Oops: 5 [#1] ARM
> > [  420.300000] Modules linked in:
> > [  420.300000] CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted
> > 4.8.0-rc2-next-20160819 #1
> > [  420.300000] Hardware name: Freescale MXS (Device Tree)
> > [  420.300000] task: c3490000 task.stack: c348e000
> > [  420.300000] PC is at usb_hcd_irq+0x0/0x34
> > [  420.300000] LR is at ci_irq+0x58/0x12c

> I am afraid the hcd is freed before the interrupt triggered. Would you
> please try below changes:
> 
> diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
> index 96ae695..61237a9 100644
> --- a/drivers/usb/chipidea/host.c
> +++ b/drivers/usb/chipidea/host.c
> @@ -103,7 +103,7 @@ static const struct ehci_driver_overrides 
> ehci_ci_overrides = {
> static irqreturn_t host_irq(struct ci_hdrc *ci)
> {
> -       return usb_hcd_irq(ci->irq, ci->hcd);
> +       return ci->hcd ? usb_hcd_irq(ci->irq, ci->hcd) : IRQ_NONE;
> }

This should not be needed.  Instead, the driver should make sure that 
the interrupt handler has been fully unregistered before the hcd is 
deallocated.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to