Re: [PATCH] usb: echi-hcd: Add ehci_setup check before echi_shutdown

From: Andy Gross
Date: Thu May 19 2016 - 17:20:55 EST


On 19 May 2016 at 05:12, Srinivas Kandagatla
<srinivas.kandagatla@xxxxxxxxxx> wrote:

<snip>

> +++ b/drivers/usb/host/ehci-hcd.c
> @@ -368,6 +368,15 @@ static void ehci_shutdown(struct usb_hcd *hcd)
> {
> struct ehci_hcd *ehci = hcd_to_ehci(hcd);
>
> + /**
> + * Protect the system from crashing at system shutdown in cases where
> + * usb host is not added yet from OTG controller driver.
> + * As ehci_setup() not done yet, so stop accessing registers or
> + * variables initialized in ehci_setup()
> + */
> + if (!ehci->sbrn)
> + return;
> +
> spin_lock_irq(&ehci->lock);
> ehci->shutdown = true;
> ehci->rh_state = EHCI_RH_STOPPING;


Should we also not check this in ehci_suspend and ehci_resume? If I
do suspend/resume, it crashes in a similar manner. I know this goes
beyond the problem scope of the patch. Perhaps I should send in an
additional patch with the code?

Are there any other places in the ehci-hcd where this needs to be checked?

Regards,

Andy