Re: [PATCH] usb ehci_iaa_watchdog fix

Alan Stern
2008-04-02T16:48:47Z

On Wed, 2 Apr 2008, Mark Lord wrote:

> Yup, that does indeed cure it.
> Here's a patch, in case you didn't already generate one:
>
> Signed-off-by: Mark Lord <mlord@pobox.com>
>
> --- rc8/drivers/usb/host/ehci-hcd.c 2008-03-11 11:18:40.000000000 -0400
> +++ linux/drivers/usb/host/ehci-hcd.c 2008-04-02 12:16:40.000000000 -0400
> @@ -289,9 +289,7 @@
> * (a) SMP races against real IAA firing and retriggering, and
> * (b) clean HC shutdown, when IAA watchdog was pending.
> */
> - if (ehci->reclaim
> - && !timer_pending(&ehci->iaa_watchdog)
> - && HC_IS_RUNNING(ehci_to_hcd(ehci)->state)) {
> + if (ehci->reclaim && !timer_pending(&ehci->iaa_watchdog)) {
> u32 cmd, status;
>
> /* If we get here, IAA is *REALLY* late. It's barely

Okay, I'm puzzled. How could this make any difference?
ehci_bus_suspend() calls end_unlink_async() anyway, whenever reclaim is
set.

Is the real problem that it does so before calling ehci_work() instead
of after calling ehci_halt()?

Mark, if you want to experiment some more, try reverting your patch
above and moving:

if (ehci->reclaim)
end_unlink_async(ehci);

in ehci-hub.c:ehci_bus_suspend() to just after the line saying:

hcd->state = HC_STATE_SUSPENDED;

Alan Stern