Re: [PATCH 5.16 regression fix 0/5] ACPI: scan: Skip turning off some unused objects during scan

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Thursday, November 18, 2021 12:15:28 PM CET Hans de Goede wrote:
> Hi,
> 
> On 11/18/21 12:08, Rafael J. Wysocki wrote:
> > On Wed, Nov 17, 2021 at 11:01 PM Hans de Goede <hdegoede@redhat.com> wrote:
> >>
> >> Hi Rafael,
> >>
> >> Commit c10383e8ddf4 ("ACPI: scan: Release PM resources blocked by
> >> unused objects") adds a:
> >>
> >>         bus_for_each_dev(&acpi_bus_type, NULL, NULL, acpi_dev_turn_off_if_unused);
> >>
> >> call to acpi_scan_init(). On some devices with buggy DSDTs calling
> >> _PS3 for one device may result in it turning off another device.
> > 
> > Well, I'm going to revert this commit.  I'm sending a pull request
> > with the revert later today.
> > 
> >> Specifically the DSDT of the GPD win and GPD pocket devices has a
> >> "\\_SB_.PCI0.SDHB.BRC1" device for a non existing SDIO wifi module
> >> which _PS3 method sets a GPIO causing the PCI wifi card to turn off.
> >>
> >> I've an earlier, in some ways simpler, fix for this here:
> >> https://fedorapeople.org/~jwrdegoede/0001-ACPI-scan-Skip-turning-off-some-unused-objects-durin.patch
> >>
> >> But the sdhci-acpi.c MMC host code already has an older workaround
> >> for it to not toggle power on this broken ACPI object; and this
> >> simpler fix would require keeping that workaround. So then we would
> >> have 2 workarounds for the same issue in the kernel.
> >>
> >> Thus instead I've come up with a slightly different approach which
> >> IMHO has ended up pretty well.
> >>
> >> Patches 1-3 of this series are this different approach and assuming
> >> they are considered ok must be merged into 5.16 to fix the regression
> >> caused by commit c10383e8ddf4 on these devices.
> > 
> > So I'll have a look at these and if they look good, we can do that
> > instead of the problematic commit in 5.17.
> 
> I'm a bit confused now, if the problematic commit is going to get
> reversed then technically we don't need this series anymore ?

That's correct.

> Or are you planning on re-introducing it in some form for 5.17 ?

I have been considering this.

> With that said getting this series merged would still be good,
> patch 1 + 2 make the existing always_present quirk code more generic
> which might be useful later. And then patch 3 (which is small)
> allows dropping some ugliness from the sdhci-acpi.c code since
> the DSDT bug we are hitting will now be solved by the
> new acpi-dev-status-override mechanism.

OK, so this would be applicable for 5.17, but a couple of changelogs
need to be updated if I'm not mistaken.

Can you please do that and resend the series?