Re: [PATCH] PCI / PM: Do not clear state_saved for devices that remain suspended

From: Mika Westerberg
Date: Fri May 18 2018 - 05:57:07 EST


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>

Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>