Re: [PATCH] nvme: Add a module parameter for users to force simple suspend

[Mario Limonciello]

On 2/28/23 16:34, Keith Busch wrote:
> On Tue, Feb 28, 2023 at 04:11:48PM -0600, Mario Limonciello wrote:
> > +static bool nvme_use_simple_suspend(struct pci_dev *pdev)
> > +{
> > +	if (!simple_suspend)
> > +		return false;
> > +	if (simple_suspend == 1)
> > +		return true;
> > +	return !noacpi && acpi_storage_d3(&pdev->dev);
> > +}
> > +
> >   static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> >   {
> >   	int node, result = -ENOMEM;
> > @@ -3128,11 +3145,7 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> >   
> >   	quirks |= check_vendor_combination_bug(pdev);
> >   
> > -	if (!noacpi && acpi_storage_d3(&pdev->dev)) {
> > -		/*
> > -		 * Some systems use a bios work around to ask for D3 on
> > -		 * platforms that support kernel managed suspend.
> > -		 */
> > +	if (nvme_use_simple_suspend(pdev)) {
> >   		dev_info(&pdev->dev,
> >   			 "platform quirk: setting simple suspend\n");
> >   		quirks |= NVME_QUIRK_SIMPLE_SUSPEND;
>
> Do you want the user setting "never" to override the driver's default quirks?

That hadn't occurred to me, but if offering a 0/1/-1 it certainly makes 
sense.  I'll add something to explicitly clear it if present for a V2.

Another way I've hypothesized that this problem (at least as reported) 
can be approached is to examine if ANY disks in the system have simple 
suspend set to apply a "global" change to all NVME disks.

If that is preferable I'm fine to spin it that way too.