+cc Eric and kexec list On Mon, Sep 17, 2012 at 2:54 AM, Huang Ying <ying.huang at intel.com> wrote: > If PCI devices are put into D3cold before kexec, because the > configuration registers of PCI devices in D3cold are not accessible. > > And if PCI bridges are put into low power state before kexec, > configuration registers of PCI devices underneath the PCI bridges are > not accessible too. > > These will make some PCI devices can not be scanned after kexec, so > resume the PCI devices in D3cold or PCI bridges in low power state > before kexec. Don't we need to resume the device even without the kexec issue? And even if it's in D1 or D2? It looks to me like pci_msi_shutdown() (and probably drv->shutdown()) depend on the device being in D0. > Signed-off-by: Huang Ying <ying.huang at intel.com> > --- > drivers/pci/pci-driver.c | 4 ++++ > 1 file changed, 4 insertions(+) > > --- a/drivers/pci/pci-driver.c > +++ b/drivers/pci/pci-driver.c > @@ -421,6 +421,10 @@ static void pci_device_shutdown(struct d > struct pci_dev *pci_dev = to_pci_dev(dev); > struct pci_driver *drv = pci_dev->driver; > > + /* Resume bridges and devices in D3cold for kexec to work properly */ > + if (pci_dev->current_state == PCI_D3cold || pci_dev->subordinate) > + pm_runtime_resume(dev); > + > if (drv && drv->shutdown) > drv->shutdown(pci_dev); > pci_msi_shutdown(pci_dev);
