Re: [RFC][PATCH -mm 3/3] PM: Disable _request_firmware before hibernation/suspend

Kay Sievers
2007-05-27T21:49:30Z

On 5/27/07, Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> On Sun, May 27, 2007 at 10:31:53PM +0200, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rjw@sisk.pl>
> >
> > Use a hibernation and suspend notifier to disable the firmware requesting
> > mechanism before a hibernation/suspend and enable it after the operation.
>
> This avoids the problem of .resume methods calling userspace while
> userspace is frozen and a resulting hang, but does it actually result in
> the drivers beginning to work again? If we remove process freezing in
> STR, this should just work[1] without the need to complicate things. On
> the other hand, if we don't want to support these functions in the
> suspend and resume methods we could just audit the kernel and remove
> them all.

What exactly is the problem we see here? The timeout of the firmware loader?
What goes wrong with frozen userspace, usually there is only a netlink
message sent from the kernel, which should be received and handled
just fine when userspace is running again.

Thanks,
Kay