Re: device model documentation 2/3

Oliver Neukum
2002-06-05T22:25:27Z

Am Mittwoch, 5. Juni 2002 21:11 schrieb Patrick Mochel:
> On Wed, 5 Jun 2002, Oliver Neukum wrote:
> > > SUSPEND_DISABLE tells the device to stop I/O transactions. When it
> > > stops transactions, or what it should do with unfinished transactions
> > > is a policy of the driver. After this call, the driver should not
> > > accept any other I/O requests.
> >
> > Does this mean that memory allocations in the suspend/resume
> > implementations must be made with GFP_NOIO respectively
> > GFP_ATOMIC ?
> > It would seem so.
>
> Why would you allocate memory on a resume transition?

We need to send messages to the device to restore state, don't we ?
Any activity on USB can allocate memory. We've had to change the API
to fix deadlock problems due to this already.

Regards
Oliver