From: Rafael J. Wysocki Date: Fri, 15 Dec 2017 02:07:18 +0000 (+0100) Subject: PCI / PM: Force devices to D0 in pci_pm_thaw_noirq() X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=74c74ba77281284e92cd37eb8dbe0cee0f20c9d9 PCI / PM: Force devices to D0 in pci_pm_thaw_noirq() commit 5839ee7389e893a31e4e3c9cf17b50d14103c902 upstream. It is incorrect to call pci_restore_state() for devices in low-power states (D1-D3), as that involves the restoration of MSI setup which requires MMIO to be operational and that is only the case in D0. However, pci_pm_thaw_noirq() may do that if the driver's "freeze" callbacks put the device into a low-power state, so fix it by making it force devices into D0 via pci_set_power_state() instead of trying to "update" their power state which is pointless. Fixes: e60514bd4485 (PCI/PM: Restore the status of PCI devices across hibernation) Reported-by: Thomas Gleixner Reported-by: Maarten Lankhorst Tested-by: Thomas Gleixner Tested-by: Maarten Lankhorst Signed-off-by: Rafael J. Wysocki Acked-by: Bjorn Helgaas Signed-off-by: Ben Hutchings --- diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index fa635079f6d3..5dde000e32bf 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -872,7 +872,12 @@ static int pci_pm_thaw_noirq(struct device *dev) if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_resume_early(dev); - pci_update_current_state(pci_dev, PCI_D0); + /* + * pci_restore_state() requires the device to be in D0 (because of MSI + * restoration among other things), so force it into D0 in case the + * driver's "freeze" callbacks put it into a low-power state directly. + */ + pci_set_power_state(pci_dev, PCI_D0); pci_restore_state(pci_dev); if (drv && drv->pm && drv->pm->thaw_noirq)