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Subject[PATCH 4.9 10/21] PCI / PM: Force devices to D0 in pci_pm_thaw_noirq()
4.9-stable review patch.  If anyone has any objections, please let me know.


From: Rafael J. Wysocki <>

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: Greg Kroah-Hartman <>

drivers/pci/pci-driver.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -953,7 +953,12 @@ 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);

if (drv && drv->pm && drv->pm->thaw_noirq)

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