Re: [PATCH] USB: fix Scheduling while atomic warning when resuming.

David Brownell
2004-12-22T04:22:43Z

On Tuesday 21 December 2004 7:48 pm, Jeff Garzik wrote:
> If we are going for a minimalist -rc patch, why not drop the lock,
> sleep, then reacquire the lock?

If that lock were dropped, what would prevent other tasks from
touching the hardware while it's sending RESUME signaling down
the bus, and thereby mucking up the resume sequence?

That 20+ msec is a protocol timer. Normally we'd want khubd
to handle such things, and then resume all the child devices,
but that's not so readily done for root hubs or during calls
from the pm core code.

- Dave