Messages in this thread | | | Subject | Re: [PATCH][RFT] PCI: Use pci_update_current_state() in pci_enable_device_flags() | From | Maximilian Luz <> | Date | Thu, 8 Jul 2021 22:33:58 +0200 |
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On 7/8/21 3:25 PM, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Updating the current_state field of struct pci_dev the way it is done > in pci_enable_device_flags() before calling do_pci_enable_device() may > not work. For example, if the given PCI device depends on an ACPI > power resource whose _STA method initially returns 0 ("off"), but the > config space of the PCI device is accessible and the power state > retrieved from the PCI_PM_CTRL register is D0, the current_state > field in the struct pci_dev representing that device will get out of > sync with the power.state of its ACPI companion object and that will > lead to power management issues going forward. > > To avoid such issues, make pci_enable_device_flags() call > pci_update_current_state() which takes ACPI device power management > into account, if present, to retrieve the current power state of the > device. > > Link: https://lore.kernel.org/lkml/20210314000439.3138941-1-luzmaximilian@gmail.com/ > Reported-by: Maximilian Luz <luzmaximilian@gmail.com> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > Hi Maximilian, > > Because commit 4514d991d992 ("PCI: PM: Do not read power state in > pci_enable_device_flags()"), the issue addressed by it is back, so > we need an alternative way to address it. > > Can you please check if this patch makes that issue go away?
Hi,
just tested this on v5.13 and it works, thanks! Feel free to add
Tested-by: Maximilian Luz <luzmaximilian@gmail.com>
Regards, Max
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