Re: [PATCH 2/2] PCI/PTM: fix in pci_disable_ptm()

From: Rafael J. Wysocki
Date: Thu Jul 07 2022 - 14:27:45 EST


On Thu, Jul 7, 2022 at 7:22 PM Rajvi Jingar
<rajvi.jingar@xxxxxxxxxxxxxxx> wrote:
>
> Set ptm_enabled from 'struct pci_dev' to 0 in pci_ptm_disable() to

I would set "Clear" here instead of "Set", but moreover ->

> save the disabled PTM state for the device.
>
> Fixes: a697f072f5da ("PCI: Disable PTM during suspend to save power")
> Signed-off-by: Rajvi Jingar <rajvi.jingar@xxxxxxxxxxxxxxx>
> ---
> drivers/pci/pcie/ptm.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c
> index 368a254e3124..746e29779c27 100644
> --- a/drivers/pci/pcie/ptm.c
> +++ b/drivers/pci/pcie/ptm.c
> @@ -44,6 +44,7 @@ void pci_disable_ptm(struct pci_dev *dev)
> pci_read_config_word(dev, ptm + PCI_PTM_CTRL, &ctrl);
> ctrl &= ~(PCI_PTM_CTRL_ENABLE | PCI_PTM_CTRL_ROOT);
> pci_write_config_word(dev, ptm + PCI_PTM_CTRL, ctrl);
> + dev->ptm_enabled = 0;

-> I don't think that this is going to work without setting
dev->ptm_enabled in pci_restore_ptm_state() if the restored state
turns out to be "enabled".

> }
>
> void pci_save_ptm_state(struct pci_dev *dev)
> --