On Fri, May 18, 2018 at 10:17:42AM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> 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)
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
I assume you'll take this one, too.
> ---
> drivers/pci/pci-driver.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> Index: linux-pm/drivers/pci/pci-driver.c
> ===================================================================
> --- linux-pm.orig/drivers/pci/pci-driver.c
> +++ linux-pm/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;
>
