On Wed, Jun 9, 2021 at 1:25 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> Hi,
>
> On 6/9/21 12:25 PM, Mika Westerberg wrote:
> > Commit 719e1f561afb ("ACPI: Execute platform _OSC also with query bit
> > clear") makes acpi_bus_osc_negotiate_platform_control() not only query
> > the platforms capabilities but it also commits the result back to the
> > firmware to report which capabilities are supported by the OS back to
> > the firmware
> >
> > On certain systems the BIOS loads SSDT tables dynamically based on the
> > capabilities the OS claims to support. However, on these systems the
> > _OSC actually clears some of the bits (under certain conditions) so what
> > happens is that now when we call the _OSC twice the second time we pass
> > the cleared values and that results errors like below to appear on the
> > system log:
> >
> > ACPI BIOS Error (bug): Could not resolve symbol [\_PR.PR00._CPC], AE_NOT_FOUND (20210105/psargs-330)
> > ACPI Error: Aborting method \_PR.PR01._CPC due to previous error (AE_NOT_FOUND) (20210105/psparse-529)
> >
> > In addition the ACPI 6.4 spec says following [1]:
> >
> > If the OS declares support of a feature in the Support Field in one
> > call to _OSC, then it must preserve the set state of that bit
> > (declaring support for that feature) in all subsequent calls.
> >
> > Based on the above we can fix the issue by passing the same set of
> > capabilities to the platform wide _OSC in both calls regardless of the
> > query flag.
> >
> > While there drop the context.ret.length checks which were wrong to begin
> > with (as the length is number of bytes not elements). This is already
> > checked in acpi_run_osc() that also returns an error in that case.
> >
> > Includes fixes by Hans de Goede.
> >
> > [1] https://uefi.org/specs/ACPI/6.4/06_Device_Configuration/Device_Configuration.html#sequence-of-osc-calls
> >
> > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=213023
> > BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1963717
> > Fixes: 719e1f561afb ("ACPI: Execute platform _OSC also with query bit clear")
> > Cc: Mario Limonciello <mario.limonciello@xxxxxxxxxxx>
> > cc: Hans de Goede <hdegoede@xxxxxxxxxx>
> > Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
>
> Thanks, patch looks good to me:
>
> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Applied as 5.13-rc material, thanks!
