4.17-stable review patch. If anyone has any objections, please let me know.
------------------
From: Rafael J. Wysocki rafael.j.wysocki@intel.com
commit 656088aa9b513907833ba091d0dcde87571fe05b upstream.
The state_saved flag should not be cleared in pci_pm_suspend() if the given device is going to remain suspended, or the device's config space will not be restored properly during the subsequent resume.
Namely, if the device is going to stay in suspend, both the late and noirq callbacks return early for it, so if its state_saved flag is cleared in pci_pm_suspend(), it will remain unset throughout the remaining part of suspend and resume and pci_restore_state() called for the device going forward will return without doing anything.
For this reason, change pci_pm_suspend() to only clear state_saved if the given device is not going to remain suspended. [This is analogous to what commit ae860a19f37c (PCI / PM: Do not clear state_saved in pci_pm_freeze() when smart suspend is set) did for hibernation.]
Fixes: c4b65157aeef (PCI / PM: Take SMART_SUSPEND driver flag into account) Cc: 4.15+ stable@vger.kernel.org # 4.15+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Reviewed-by: Mika Westerberg mika.westerberg@linux.intel.com Acked-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/pci/pci-driver.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -753,10 +753,11 @@ static int pci_pm_suspend(struct device * better to resume the device from runtime suspend here. */ if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || - !pci_dev_keep_suspended(pci_dev)) + !pci_dev_keep_suspended(pci_dev)) { pm_runtime_resume(dev); + pci_dev->state_saved = false; + }
- pci_dev->state_saved = false; if (pm->suspend) { pci_power_t prev = pci_dev->current_state; int error;