RE: [PATCH AUTOSEL for 4.4 093/167] ACPICA: Recognize the Windows 10 version 1607 and 1703 OSI strings

[Moore, Robert]

> -----Original Message-----
> From: Mario.Limonciello@xxxxxxxx [mailto:Mario.Limonciello@xxxxxxxx]
> Sent: Wednesday, March 28, 2018 10:18 AM
> To: Moore, Robert <robert.moore@xxxxxxxxx>;
> Alexander.Levin@xxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> stable@xxxxxxxxxxxxxxx
> Cc: Schmauss, Erik <erik.schmauss@xxxxxxxxx>; Wysocki, Rafael J
> <rafael.j.wysocki@xxxxxxxxx>
> Subject: RE: [PATCH AUTOSEL for 4.4 093/167] ACPICA: Recognize the
> Windows 10 version 1607 and 1703 OSI strings
> 
> > -----Original Message-----
> > From: Moore, Robert [mailto:robert.moore@xxxxxxxxx]
> > Sent: Wednesday, March 28, 2018 12:16 PM
> > To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>;
> > Alexander.Levin@xxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> > stable@xxxxxxxxxxxxxxx
> > Cc: Schmauss, Erik <erik.schmauss@xxxxxxxxx>; Wysocki, Rafael J
> > <rafael.j.wysocki@xxxxxxxxx>
> > Subject: RE: [PATCH AUTOSEL for 4.4 093/167] ACPICA: Recognize the
> > Windows 10 version 1607 and 1703 OSI strings
> >
> >
> >
> > > -----Original Message-----
> > > From: Mario.Limonciello@xxxxxxxx [mailto:Mario.Limonciello@xxxxxxxx]
> > > Sent: Monday, March 26, 2018 12:30 AM
> > > To: Alexander.Levin@xxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> > > stable@xxxxxxxxxxxxxxx
> > > Cc: Moore, Robert <robert.moore@xxxxxxxxx>; Schmauss, Erik
> > > <erik.schmauss@xxxxxxxxx>; Wysocki, Rafael J
> > > <rafael.j.wysocki@xxxxxxxxx>
> > > Subject: RE: [PATCH AUTOSEL for 4.4 093/167] ACPICA: Recognize the
> > > Windows 10 version 1607 and 1703 OSI strings
> > >
> > > > -----Original Message-----
> > > > From: Sasha Levin [mailto:Alexander.Levin@xxxxxxxxxxxxx]
> > > > Sent: Monday, March 19, 2018 11:07 AM
> > > > To: linux-kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx
> > > > Cc: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>; Bob Moore
> > > > <robert.moore@xxxxxxxxx>; Erik Schmauss <erik.schmauss@xxxxxxxxx>;
> > > Rafael J .
> > > > Wysocki <rafael.j.wysocki@xxxxxxxxx>; Sasha Levin
> > > > <Alexander.Levin@xxxxxxxxxxxxx>
> > > > Subject: [PATCH AUTOSEL for 4.4 093/167] ACPICA: Recognize the
> > > > Windows
> > > > 10 version 1607 and 1703 OSI strings
> > > >
> > > > From: Mario Limonciello <mario.limonciello@xxxxxxxx>
> > > >
> > > > [ Upstream commit bc4d413a819f9d0764a80a55875a5d7e1f4efed4 ]
> > > >
> > > > ACPICA commit 35a4a3ea723b3066f575e63e5f0116f7ce65e713
> > > >
> > > > The public Microsoft document listing recognized OSI strings [1]
> > > > shows that these two strings were introduced.
> > > > version 1607 / Anniversary Update / "Redstone 1"
> > > > version 1703 / Creators Update / "Redstone 2"
> > > >
> > > > [1]
> > > > http://download.microsoft.com/download/7/e/7/7e7662cf-cbea-470b-a9
> > > > 7e-
> > > > ce7ce0d98dc2/winacpi_osi.docx
> > > >
> > > > Link: https://github.com/acpica/acpica/commit/35a4a3ea
> > > > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxxx>
> > > > Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx>
> > > > Signed-off-by: Erik Schmauss <erik.schmauss@xxxxxxxxx>
> > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > > > Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
> > > > ---
> > > >  drivers/acpi/acpica/utosi.c | 2 ++
> > > >  include/acpi/actypes.h      | 2 ++
> > > >  2 files changed, 4 insertions(+)
> > > >
> > > > diff --git a/drivers/acpi/acpica/utosi.c
> > > > b/drivers/acpi/acpica/utosi.c index 8f3d203aed79..51d9011b5b33
> > > > 100644
> > > > --- a/drivers/acpi/acpica/utosi.c
> > > > +++ b/drivers/acpi/acpica/utosi.c
> > > > @@ -101,6 +101,8 @@ static struct acpi_interface_info
> > > > acpi_default_supported_interfaces[] = {
> > > >  	{"Windows 2012", NULL, 0, ACPI_OSI_WIN_8},	/* Windows 8 and
> Server
> > > > 2012 - Added 08/2012 */
> > > >  	{"Windows 2013", NULL, 0, ACPI_OSI_WIN_8},	/* Windows 8.1 and
> > > Server
> > > > 2012 R2 - Added 01/2014 */
> > > >  	{"Windows 2015", NULL, 0, ACPI_OSI_WIN_10},	/* Windows 10
> -
> > > Added
> > > > 03/2015 */
> > > > +	{"Windows 2016", NULL, 0, ACPI_OSI_WIN_10_RS1},	/* Windows 10
> > > > version 1607 - Added 12/2017 */
> > > > +	{"Windows 2017", NULL, 0, ACPI_OSI_WIN_10_RS2},	/* Windows 10
> > > > version 1703 - Added 12/2017 */
> > > >
> > > >  	/* Feature Group Strings */
> > > >
> > > > diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index
> > > > f914958c4adb..d27bc051f47f 100644
> > > > --- a/include/acpi/actypes.h
> > > > +++ b/include/acpi/actypes.h
> > > > @@ -1284,6 +1284,8 @@ typedef enum {
> > > >  #define ACPI_OSI_WIN_7                  0x0B
> > > >  #define ACPI_OSI_WIN_8                  0x0C
> > > >  #define ACPI_OSI_WIN_10                 0x0D
> > > > +#define ACPI_OSI_WIN_10_RS1             0x0E
> > > > +#define ACPI_OSI_WIN_10_RS2             0x0F
> > > >
> > > >  /* Definitions of file IO */
> > > >
> > > > --
> > > > 2.14.1
> > >
> > > I don't believe that it would be a good idea to bring back this
> > > patch to kernels older than 4.15.  These strings do activate some
> > > extra features in Windows and some BIOS ASL has been written to only
> > > activate them when the newer Windows versions are detected. I have
> > > no concerns bringing them to 4.15 though.
> > >
> > > Bringing them back to stable may introduce other problems that
> > > requires backporting additional driver changes too.
> >
> > [Moore, Robert]
> >
> > There should be no problem with this change concerning older machines.
> > The firmware on these machines will simply never call _OSI with any
> > strings newer than when the firmware was written -- including this new
> one.
> >
> > Bob
> 
> Actually I'm referring to "newer" machines that do have this string in
> the firmware but the changes in the kernel that are relevant to the
> string didn't land until newer kernels.
> 
> I think it's a pretty good risk for regressions on those older stable
> kernels as such.

I don't think I have heard of any issues like this in the past, but I could be wrong. You might look into the past when other new strings have been added to ACPICA. We add a new string every 1-2 years, depending when MS releases a new one.