From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> 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) Cc: 4.13+ <stable@xxxxxxxxxxxxxxx> # 4.13+ Reported-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reported-by: Maarten Lankhorst <dev@xxxxxxxxxxxxxx> Tested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Tested-by: Maarten Lankhorst <dev@xxxxxxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- The bug is not as old as I thought, actually. Yes, we did the pci_update_current_state() in pci_pm_thaw_noirq() forever, but it started to be problematic in 4.13, when we started to call pci_restore_state() in addition to it to fix another issue. --- drivers/pci/pci-driver.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) Index: linux-pm/drivers/pci/pci-driver.c =================================================================== --- linux-pm.orig/drivers/pci/pci-driver.c +++ linux-pm/drivers/pci/pci-driver.c @@ -1027,7 +1027,12 @@ static int pci_pm_thaw_noirq(struct devi 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)
