Re: [BUGFIX 2/2] PCI/PM: Resume device before shutdown

[Huang Ying <ying.huang@intel.com>]

On Fri, 2012-11-02 at 10:52 -0600, Bjorn Helgaas wrote:
> On Wed, Oct 24, 2012 at 12:54 AM, Huang Ying <ying.huang@intel.com> wrote:
> > Some actions during shutdown need device to be in D0 state, such as
> > MSI shutdown etc, so resume device before shutdown.
> 
> Is there a problem report or bugzilla for this issue?  What are the
> symptoms by which a user could figure out that he needs this fix?

No bugzilla for this issue.  This issue will cause the corresponding
device lost in kexeced kernel.

Best Regards,
Huang Ying

> Should this be put in the stable tree as well?  If so, for v3.6 only?
> 
> > Signed-off-by: Huang Ying <ying.huang@intel.com>
> > ---
> >  drivers/pci/pci-driver.c |   12 ++----------
> >  1 file changed, 2 insertions(+), 10 deletions(-)
> >
> > --- a/drivers/pci/pci-driver.c
> > +++ b/drivers/pci/pci-driver.c
> > @@ -398,6 +398,8 @@ static void pci_device_shutdown(struct d
> >         struct pci_dev *pci_dev = to_pci_dev(dev);
> >         struct pci_driver *drv = pci_dev->driver;
> >
> > +       pm_runtime_resume(dev);
> > +
> >         if (drv && drv->shutdown)
> >                 drv->shutdown(pci_dev);
> >         pci_msi_shutdown(pci_dev);
> > @@ -408,16 +410,6 @@ static void pci_device_shutdown(struct d
> >          * continue to do DMA
> >          */
> >         pci_disable_device(pci_dev);
> > -
> > -       /*
> > -        * Devices may be enabled to wake up by runtime PM, but they need not
> > -        * be supposed to wake up the system from its "power off" state (e.g.
> > -        * ACPI S5).  Therefore disable wakeup for all devices that aren't
> > -        * supposed to wake up the system at this point.  The state argument
> > -        * will be ignored by pci_enable_wake().
> > -        */
> > -       if (!device_may_wakeup(dev))
> > -               pci_enable_wake(pci_dev, PCI_UNKNOWN, false);
> >  }
> >
> >  #ifdef CONFIG_PM